HomeMy WebLinkAboutCT 2022-0003; CARLSBAD BY THE SEA SUMMERHOUSE; PRELIMINARY STORM WATER QUALITY MANAGEMENT PLAN (SWQMP); 2024-01-19CITY OF CARLSBAD
PRIORITY DEVELOPMENT PROJECT (PDP)
PRELIMINARY STORM WATER QUALITY MANAGEMENT PLAN
(SWQMP)
FOR
CARLSBAD BY THE SEA SUMMER HOUSE
FRONT PORCH COMMUNITIES AND SERVICES
CT 2022-0003/CUP 2022-0014/CDP 2022-0047 SDP2022-0011 (DEV2022-0063)
ENGINEER OF WORK:
PREPARED FOR:
Joan Johnson, Executive Director
Front Porch Communities
800 North Brand Blvd. 19th Floor
Glendale, Ca 92103
PREPARED BY:
BWE, INC.
9449 Balboa Avenue
San Diego, Ca 92123
(619) 299-5550
DATE:
November 1, 2022
REV: June 1, 2023
REV: September 1, 2023
REV: November 1, 2023
REV: January 19, 2024
TABLE OF CONTENTS
Certification Page
Project Vicinity Map
FORM E-34 Storm Water Standard Questionnaire
Site Information
FORM E-36 Standard Project Requirement Checklist
Summary of PDP Structural BMPs
Attachment 1: Backup for PDP Pollutant Control BMPs
Attachment 1a: DMA Exhibit
Attachment 1b: Tabular Summary of DMAs and Design Capture Volume Calculations
Attachment 1c: Harvest and Use Feasibility Screening (when applicable)
Attachment 1d: Infiltration Feasibility Analysis (when applicable)
Attachment 1e: Pollutant Control BMP Design Worksheets / Calculations
Attachment 1f: Trash Capture BMP Requirements
Attachment 2: Backup for PDP Hydromodification Control Measures
Attachment 2a: Hydromodification Management Exhibit
Attachment 2b: Management of Critical Coarse Sediment Yield Areas
Attachment 2c: Geomorphic Assessment of Receiving Channels
Attachment 2d: Flow Control Facility Design
Attachment 3: Structural BMP Maintenance Thresholds and Actions Attachment
4: Single Sheet BMP (SSBMP) Exhibit
CERTIFICATION PAGE
Project Name: CARLSBAD BY THE SEA SUMMER HOUSE
Project ID: CT 2022-0003/CUP 2022-0014/CDP 2022-0047 SDP2022-0011 (DEV2022-0063)
I hereby declare that I am the Engineer in Responsible Charge of design of storm water BMPs for
this project, and that I have exercised responsible charge over the design of the project as defined
in Section 6703 of the Business and Professions Code, and that the design is consistent with the
requirements of the BMP Design Manual, which is based on the requirements of SDRWQCB
Order No. R9-2013-0001 (MS4 Permit) or the current Order.
I have read and understand that the City Engineer has adopted minimum requirements for
managing urban runoff, including storm water, from land development activities, as described in
the BMP Design Manual. I certify that this SWQMP has been completed to the best of my ability
and accurately reflects the project being proposed and the applicable source control and site
design BMPs proposed to minimize the potentially negative impacts of this project's land
development activities on water quality. I understand and acknowledge that the plan check review
of this SWQMP by the City Engineer is confined to a review and does not relieve me, as the
Engineer in Responsible Charge of design of storm water BMPs for this project, of my
responsibilities for project design.
RCE 86216 Exp. 12-31-24
Engineer of Work's Signature, PE Number & Expiration Date
Hector Maytorena
Print Name
BWE, Inc.
Company
01-19-2024
Date
PROJECT VICINITY MAP
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INSTRUCTIONS:
To address post-development pollutants that may be generated from development projects, the city requires that new
development and significant redevelopment priority projects incorporate Permanent Storm Water Best Management
Practices (BMPs) into the project design per Carlsbad BMP Design Manual (BMP Manual). To view the BMP Manual, refer
to the Engineering Standards (Volume 5).
This questionnaire must be completed by the applicant in advance of submitting for a development application (subdivision,
discretionary permits and/or construction permits). The results of the questionnaire determine the level of storm water
standards that must be applied to a proposed development or redevelopment project. Depending on the outcome, your
project will either be subject to ‘STANDARD PROJECT’ requirements, “PRIORITY DEVELOPMENT PROJECT (PDP)
requirements or not considered a development project. This questionnaire will also determine if the project is subject to
TRASH CAPTURE REQUIREMENTS.
Your responses to the questionnaire represent an initial assessment of the proposed project conditions and impacts. City
staff has responsibility for making the final assessment after submission of the development application. If staff determines
that the questionnaire was incorrectly filled out and is subject to more stringent storm water standards than initially assessed
by you, this will result in the return of the development application as incomplete. In this case, please make the changes to
the questionnaire and resubmit to the city.
If you are unsure about the meaning of a question or need help in determining how to respond to one or more of the
questions, please seek assistance from Land Development Engineering staff.
A completed and signed questionnaire must be submitted with each development project application. Only one completed
and signed questionnaire is required when multiple development applications for the same project are submitted
concurrently.
PROJECT INFORMATION
PROJECT NAME:CARLSBAD BY THE SEA SUMMER HOUSE APN: 2031440400, 2031440500,
2031440600, 2031440700,
2031440800 ADDRESS: 2710; 2720; 2730 AND 2740 Ocean Street Carlsbad, CA 92008
The project is (check one): xNew Development Redevelopment
The total proposed disturbed area is: 26,893 ft2 ( 0.62 ) acres
The total proposed newly created and/or replaced impervious area is: 23,043 ft2 ( 0.53 ) acres
If your project is covered by an approved SWQMP as part of a larger development project, provide the project ID and the
SWQMP # of the larger development project:
Project ID SWQMP #:
Then, go to Step 1 and follow the instructions. When completed, sign the form at the end and submit this with your
application to the city.
This Box for City Use Only
City Concurrence:
YES NO Date: Project ID:
By:
E-34 Page 1 of 4 REV 08/22
STEP 1
TO BE COMPLETED FOR ALL PROJECTS
To determine if your project is a “development project”, please answer the following question:
YES
NO
Is your project LIMITED TO routine maintenance activity and/or repair/improvements to an existing building
or structure that do not alter the size (See Section 1.3 of the BMP Design Manual for guidance)?
x
If you answered “yes” to the above question, provide justification below then go to Step 6, mark the box stating “my project
is not a ‘development project’ and not subject to the requirements of the BMP manual” and complete applicant information.
Justification/discussion: (e.g. the project includes only interior remodels within an existing building):
If you answered “no” to the above question, the project is a ‘development project’, go to Step 2.
STEP 2
TO BE COMPLETED FOR ALL DEVELOPMENT PROJECTS
To determine if your project is exempt from PDP requirements pursuant to MS4 Permit Provision E.3.b.(3), please answer
the following questions:
Is your project LIMITED to one or more of the following:
YES
NO
1. Constructing new or retrofitting paved sidewalks, bicycle lanes or trails that meet the following criteria:
a) Designed and constructed to direct storm water runoff to adjacent vegetated areas, or other non-
erodible permeable areas; OR
b) Designed and constructed to be hydraulically disconnected from paved streets or roads; OR
c) Designed and constructed with permeable pavements or surfaces in accordance with USEPA
Green Streets guidance?
x
2. Retrofitting or redeveloping existing paved alleys, streets, or roads that are designed and constructed in
accordance with the USEPA Green Streets guidance?
x
3. Ground Mounted Solar Array that meets the criteria provided in section 1.4.2 of the BMP manual?
x
If you answered “yes” to one or more of the above questions, provide discussion/justification below, then go to Step 6, mark
the second box stating “my project is EXEMPT from PDP …” and complete applicant information.
Discussion to justify exemption (e.g. the project redeveloping existing road designed and constructed in accordance with
the USEPA Green Street guidance):
If you answered “no” to the above questions, your project is not exempt from PDP, go to Step 3.
E-34 Page 2 of 4 REV 08/22
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STEP 3
TO BE COMPLETED FOR ALL NEW OR REDEVELOPMENT PROJECTS
To determine if your project is a PDP, please answer the following questions (MS4 Permit Provision E.3.b.(1)):
YES NO
1. Is your project a new development that creates 10,000 square feet or more of impervious surfaces
collectively over the entire project site? This includes commercial, industrial, residential, mixed-use,
and public development projects on public or private land.
x
2. Is your project a redevelopment project creating and/or replacing 5,000 square feet or more of impervious
surface collectively over the entire project site on an existing site of 10,000 square feet or more of
impervious surface? This includes commercial, industrial, residential, mixed-use, and public
development projects on public or private land.
x
3. Is your project a new or redevelopment project that creates and/or replaces 5,000 square feet or more of
impervious surface collectively over the entire project site and supports a restaurant? A restaurant is a
facility that sells prepared foods and drinks for consumption, including stationary lunch counters and
refreshment stands selling prepared foods and drinks for immediate consumption (Standard Industrial
Classification (SIC) code 5812).
x
4. Is your project a new or redevelopment project that creates 5,000 square feet or more of impervious
surface collectively over the entire project site and supports a hillside development project? A hillside
development project includes development on any natural slope that is twenty-five percent or greater.
x
5. Is your project a new or redevelopment project that creates and/or replaces 5,000 square feet or more of
impervious surface collectively over the entire project site and supports a parking lot? A parking lot is a
land area or facility for the temporary parking or storage of motor vehicles used personally for
business or for commerce.
x
6. Is your project a new or redevelopment project that creates and/or replaces 5,000 square feet or more
of impervious street, road, highway, freeway or driveway surface collectively over the entire project
site? A street, road, highway, freeway or driveway is any paved impervious surface used for the
transportation of automobiles, trucks, motorcycles, and other vehicles.
x
7. Is your project a new or redevelopment project that creates and/or replaces 2,500 square feet or more of
impervious surface collectively over the entire site, and discharges directly to an Environmentally
Sensitive Area (ESA)? “Discharging Directly to” includes flow that is conveyed overland a distance of 200
feet or less from the project to the ESA, or conveyed in a pipe or open channel any distance as an
isolated flow from the project to the ESA (i.e. not commingled with flows from adjacent lands).*
x
8. Is your project a new development or redevelopment project that creates and/or replaces 5,000 square
feet or more of impervious surface that supports an automotive repair shop? An automotive repair
shop is a facility that is categorized in any one of the following Standard Industrial Classification (SIC)
codes: 5013, 5014, 5541, 7532-7534, or 7536-7539.
x
9. Is your project a new development or redevelopment project that creates and/or replaces 5,000 square
feet or more of impervious area that supports a retail gasoline outlet (RGO)? This category includes
RGO’s that meet the following criteria: (a) 5,000 square feet or more or (b) a project Average Daily
Traffic (ADT) of 100 or more vehicles per day.
x
10. Is your project a new or redevelopment project that results in the disturbance of one or more acres of land
and are expected to generate pollutants post construction?
x
11. Is your project located within 200 feet of the Pacific Ocean and (1) creates 2,500 square feet or more of
impervious surface or (2) increases impervious surface on the property by more than 10%? (CMC
21.203.040)
x
If you answered “yes” to one or more of the above questions, your project is a PDP. If your project is a redevelopment
project, go to step 4. If your project is a new project, go to step 5, complete the trash capture question.
If you answered “no” to all of the above questions, your project is a ‘STANDARD PROJECT’. Go to step 5, complete the
trash capture question.
* Environmentally Sensitive Areas include but are not limited to all Clean Water Act Section 303(d) impaired water bodies; areas designated as Areas of Special
Biological Significance by the State Water Resources Control Board (Water Quality Control Plan for the San Diego Basin (1994) and amendments); water bodies
designated with the RARE beneficial use by the State Water Resources Control Board (Water Quality Control Plan for the San Diego Basin (1994) and amendments);
areas designated as preserves or their equivalent under the Multi Species Conservation Program within the Cities and County of San Diego; Habitat Management
Plan; and any other equivalent environmentally sensitive areas which have been identified by the City.
E-34 Page 3 of 4 REV 08/22
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STEP 4
TO BE COMPLETED FOR REDEVELOPMENT PROJECTS THAT ARE PRIORITY DEVELOPMENT PROJECTS (PDP)
ONLY
Complete the questions below regarding your redevelopment project (MS4 Permit Provision E.3.b.(2)):
YES
NO
Does the redevelopment project result in the creation or replacement of impervious surface in an amount of
less than 50% of the surface area of the previously existing development? Complete the percent impervious
calculation below:
Existing impervious area (A) = sq. ft.
Total proposed newly created or replaced impervious area (B) = sq. ft.
Percent impervious area created or replaced (B/A)*100 = %
If you answered “yes”, the structural BMPs required for PDP apply only to the creation or replacement of impervious surface
and not the entire development. Go to step 5, complete the trash capture question.
If you answered “no,” the structural BMP’s required for PDP apply to the entire development. Go to step 5, complete the
trash capture question.
STEP 5
TO BE COMPLETED FOR ALL DEVELOPMENT PROJECTS
Complete the question below regarding your Project (SDRWQCB Order No. 2017-0077):
YES
NO
Is the Project within any of the following Priority Land Use (PLU) categories and not exempt from trash
capture requirements per section 4.4.2.2 of the BMP Manual?
R-23 (15-23 du/ac), R-30 (23-30 du/ac), PI (Planned Industrial), CF (Community Facilities), GC (General
Commercial), L (Local Shopping Center), R (Regional Commercial), V-B (Village-Barrio), VC (Visitor
Commercial), O (Office), VC/OS (Visitor Commercial/Open Space), PI/O (Planned Industrial/Office), or
Public Transportation Station
x
If you answered “yes”, the ‘PROJECT’ is subject to TRASH CAPTURE REQUIREMENTS. Go to step 6, check the first
box stating, “My project is subject to TRASH CAPTURE REQUIREMENTS …” and the second or third box as
determined in step 3.
If you answered “no”, Go to step 6, check the second or third box as determined in step 3. List exemption if applicable
for ‘no’ answer here: project site is designated as R-15, residential 8-15 du/ac which is not listed under section
4.4.2.2 of the BMP Manual.
STEP 6
CHECK THE APPROPRIATE BOX(ES) AND COMPLETE APPLICANT INFORMATION
My project is subject to TRASH CAPTURE REQUIREMENTS and must comply with TRASH CAPTURE
REQUIREMENTS of the BMP Manual. I understand I must prepare a Storm Water Quality Management Plan (SWQMP).
My project is a ‘STANDARD PROJECT’ OR EXEMPT from PDP and must only comply with ‘STANDARD PROJECT’
stormwater requirements of the BMP Manual. I will submit a “Standard Project Requirement Checklist Form E-36”. If my
project is subject to TRASH CAPTURE REQUIREMENTS, I will submit a TRASH CAPTURE Storm Water Quality
Management Plan (TCSWQMP) per E-35A.
xMy project is a PDP and must comply with PDP stormwater requirements of the BMP Manual. I understand I must
prepare a Storm Water Quality Management Plan (SWQMP) per E-35 template for submittal at time of application.
Note: For projects that are close to meeting the PDP threshold, staff may require detailed impervious area calculations
and exhibits to verify if ‘STANDARD PROJECT’ stormwater requirements apply.
My project is NOT a ‘development project’ and is not subject to the requirements of the BMP Manual.
Applicant Information and Signature Box
Applicant Name: Hector Maytorena Applicant Title: Principal Associate
Applicant Signature: Date: 01-19-2024
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#-D
SITE INFORMATION CHECKLIST
Project Summary Information
Project Name
CARLSBAD BY THE SEA SUMMER HOUSE
FRONT PORCH COMMUNITIES AND SERVICES
Project ID
CT 2022-0003/CUP 2022-0014/CDP 2022-0047
SDP2022-0011 (DEV2022-0063)
Project Address 2710; 2720; 2730 AND 2740 Ocean Street Carlsbad,
CA 92008
Assessor's Parcel Number(s)
(APN(s))
2031440400, 2031440500, 2031440600, 2031440700,
2031440800
Project Watershed (Hydrologic Unit) Carlsbad 904
Parcel Area
0.62 Acres ( 26,893 _ Square Feet)
Existing Impervious Area
(subset of Parcel Area)
0.0 Acres ( 0 _ Square Feet)
Area to be disturbed by the project
(Project Area)
0.76 Acres ( 33,154 Square Feet)
Project Proposed Impervious Area
(subset of Project Area)
0.64 Acres ( 27,887 Square Feet)
Project Proposed Pervious Area
(subset of Project Area)
0.12 Acres ( 5,267 Square Feet)
Note: Proposed Impervious Area + Proposed Pervious Area = Area to be Disturbed by the
Project. This may be less than the Parcel Area.
Description of Existing Site Condition and Drainage Patterns
Current Status of the Site (select all that apply):
Existing development
X Previously graded but not built out
Agricultural or other non-impervious use
Vacant, undeveloped/natural
Description / Additional Information:
Site has historically been vacant and was previously graded.
Existing Land Cover Includes (select all that apply):
Vegetative Cover
X Non-Vegetated Pervious Areas
Impervious Areas
Description / Additional Information:
Site has historically been vacant and was previously graded but not built out.
Underlying Soil belongs to Hydrologic Soil Group (select all that apply):
NRCS Type A
X NRCS Type B
NRCS Type C
NRCS Type D
Approximate Depth to Groundwater (GW):
GW Depth < 5 feet
5 feet < GW Depth < 10 feet
10 feet < GW Depth < 20 feet
X GW Depth > 20 feet (±32 feet deep)_
Existing Natural Hydrologic Features (select all that apply):
Watercourses
Seeps
Springs
Wetlands
X None
Description / Additional Information:
No known existing natural hydrologic features are known to exist.
Description of Existing Site Topography and Drainage [How is storm water runoff conveyed from
the site? At a minimum, this description should answer (1) whether existing drainage conveyance
is natural or urban; (2) describe existing constructed storm water conveyance systems, if
applicable; and (3) is runoff from offsite conveyed through the site? if so, describe]:
Currently the site is completely earthen and has no known storm water appurtenances onsite.
The site slopes from east to west with the high side of the site adjacent to Garfield Street and
the low side located along Ocean Street. The site is bordered by existing public sidewalk, gutter,
and a wall to the south. No offsite runoff is conveyed through the site. The onsite runoff sheet
flows into the curb & gutter on Ocean Street. The project site runoff is conveyed in the gutter
north to an existing public curb inlet on Ocean Street. The project site storm water enters the
public existing storm drain system and travels south where it is ultimately discharged into the
Pacific Ocean approximately 600 feet near the intersection of Ocean Street and Christiansen
Way.
Description of Proposed Site Development and Drainage Patterns
Project Description / Proposed Land Use and/or Activities:
The project proposes the consolidation of 5 adjacent parcels for the development of a multilevel
building. The new building (+/- 38,000 SF) in the consolidated lot (+/- 26,892 SF) is proposed
as a "Professional Services" use facility that will be operated under the same license as the
adjacent Carlsbad By the Sea Retirement community. The proposed building will consist of the
following: Basement Level: Parking will be located in the basement level with a total of 30
Vehicular Parking Spaces,
Level 1(Ocean Street Grade Level): 19 Memory Care Beds
Level 2 (Garfield Street Grade Level): 16 Licensed Residential Professional Care Beds in 10
Units.
Level 3 (Upper Level with Roof Terrace): 7 Licensed Residential Professional Care Beds in 5
Units
List/describe proposed impervious features of the project (e.g., buildings, roadways, parking
lots, courtyards, athletic courts, other impervious features):
Courtyards, Roof, Walkways, and outdoor patio amenity spaces
List/describe proposed pervious features of the project (e.g., landscape areas):
Landscaping, elevated planters, green roofs
Does the project include grading and changes to site topography?
X Yes
No
Description / Additional Information:
Does the project include changes to site drainage (e.g., installation of new storm water
conveyance systems)?
X Yes
No
Description / Additional Information:
Identify whether any of the following features, activities, and/or pollutant source areas will be
present (select all that apply):
X On-site storm drain inlets
X Interior floor drains and elevator shaft sump pumps
X Interior parking garages
X Need for future indoor & structural pest control
X Landscape/Outdoor Pesticide Use
Pools, spas, ponds, decorative fountains, and other water features
X Food service
X Refuse areas
Industrial processes
Outdoor storage of equipment or materials
Vehicle and Equipment Cleaning
Vehicle/Equipment Repair and Maintenance
Fuel Dispensing Areas
Loading Docks
X Fire Sprinkler Test Water
Miscellaneous Drain or Wash Water
X Plazas, sidewalks, and parking lots
Identification of Receiving Water Pollutants of Concern
Describe path of storm water from the project site to the Pacific Ocean (or bay, lagoon, lake or
reservoir, as applicable):
Storm water enters into an existing City of Carlsbad Public Storm drain system and dischargers
into the Pacific ocean approximate 600 LF
Pacific Ocean Shoreline, Buena Vista Creek HA, at Carlsbad State Beach at Carlsbad Village
List any 303(d) impaired water bodies within the path of storm water from the project site to the
Pacific Ocean (or bay, lagoon, lake or reservoir, as applicable), identify the
pollutant(s)/stressor(s) causing impairment, and identify any TMDLs for the impaired water
bodies:
303(d) Impaired Water Body Pollutant(s)/Stressor(s) TMDLs
Pacific Ocean N/A N/A
Identification of Project Site Pollutants
Identify pollutants anticipated from the project site based on all proposed use(s) of the site (see
Table B.6-1 below):
Pollutant
Not Applicable to the
Project Site
Anticipated from the
Project Site
Also a Receiving
Water Pollutant of
Concern
Sediment
X
Nutrients
X
Heavy Metals
X
Organic Compounds
X
Trash & Debris
X
Oxygen Demanding
Substances
X
Oil & Grease
X
Bacteria & Viruses
X
Pesticides
X
Anticipated and Potential Pollutants Generated by Land Use Type
Priority
Project
Categories
General Pollutant Categories
Sediment
Nutrients
Heavy
Metals
Organic
Compounds
Trash &
Debris
Oxygen
Demanding
Substances
Oil &
Grease
Bacteria &
Viruses
Pesticides
Detached
Residential
Development
X
X
X
X
X
X
X
Attached
Residential
Development
X
X
X
P(1)
P(2)
P
X
Commercial
Development
>one acre
P(1)
P(1)
X
P(2)
X
P(5)
X
P(3)
P(5)
Heavy
Industry
X
X
X
X
X
X
Automotive
Repair Shops
X
X(4)(5)
X
X
Restaurants
X
X
X
X
P(1)
Hillside
Development
>5,000 ft2
X
X
X
X
X
X
Parking Lots
P(1)
P(1)
X
X
P(1)
X
P(1)
Retail
Gasoline
Outlets
X
X
X
X
X
Streets,
Highways &
Freeways
X
P(1)
X
X(4)
X
P(5)
X
X
P(1)
X = anticipated
P = potential
(1) A potential pollutant if landscaping exists onsite.
(2) A potential pollutant if the project includes uncovered parking areas.
(3) A potential pollutant if land use involves food or animal waste products.
(4) Including petroleum hydrocarbons.
(5) Including solvents.
Trash Capture BMP Requirements
The project must meet the following Trash Capture BMP Requirements (see Section 4.4 of the
BMP Design Manual): 1) The trash capture BMP is sized for a one-year, one-hour storm event
or equivalent storm drain system, and 2) the trash capture BMP captures trash equal or greater
to 5mm.
Description / Discussion of Trash Capture BMPs:
The project site is not subject to trash capture BMPs due to land use designation.
Hydromodification Management Requirements
Do hydromodification management requirements apply (see Section 1.6 of the BMP Design
Manual)?
Yes, hydromodification management flow control structural BMPs required.
No, the project will discharge runoff directly to existing underground storm drains discharging
directly to water storage reservoirs, lakes, enclosed embayments, or the Pacific Ocean.
No, the project will discharge runoff directly to conveyance channels whose bed and bank are
concrete-lined all the way from the point of discharge to water storage reservoirs, lakes,
enclosed embayments, or the Pacific Ocean.
X No, the project will discharge runoff directly to an area identified as appropriate for an
exemption by the WMAA for the watershed in which the project resides.
Description / Additional Information (to be provided if a 'No' answer has been selected above):
Project site directly discharges into and existing curb inlet located near the point of curb return
located on the southerly corner of Ocean Street and Beech Avenue. An existing public 18” RCP
storm drain travels south within Ocean Street and ultimate discharges through an existing RCP
pipe within the beach near the intersection of Christiansen Way and Ocean Street. This route is
identified as exempt from Hydromodification per Carlsbad Watershed Management Area HU
904.00 of the WMAA. See WMAA Maps in Attachment 2.
Figure 1-2, Node 2 – As allowed by the MS4 Permit, projects discharging directly to the Pacific
Ocean, by either existing underground storm drain systems or conveyance channels whose bed
and bank are concrete-lined all the way from the point of discharge to the Pacific Ocean, are
exempt.
Critical Coarse Sediment Yield Areas*
*This Section only required if hydromodification management requirements apply
Based on the maps provided within the WMAA, do potential critical coarse sediment yield areas
exist within the project drainage boundaries?
Yes
X No, no critical coarse sediment yield areas to be protected based on WMAA maps
If yes, have any of the optional analyses presented in Appendix H of the manual been
performed?
H.6.1 Site-Specific GLU Analysis
H.7 Downstream Systems Sensitivity to Coarse Sediment
H.7.3 Coarse Sediment Source Area Verification
No optional analyses performed, the project will avoid critical coarse sediment yield areas
identified based on WMAA maps
If optional analyses were performed, what is the final result?
No critical coarse sediment yield areas to be protected based on verification of GLUs onsite.
Critical coarse sediment yield areas exist but additional analysis has determined that
protection is not required. Documentation attached in Attachment 8 of the SWQMP.
Critical coarse sediment yield areas exist and require protection. The project will implement
management measures described in Sections H.2, H.3, and H.4 as applicable, and the areas
are identified on the SWQMP Exhibit.
Discussion / Additional Information:
Flow Control for Post-Project Runoff*
*This Section only required if hydromodification management requirements apply
List and describe point(s) of compliance (POCs) for flow control for hydromodification
management (see Section 6.3.1). For each POC, provide a POC identification name or number
correlating to the project's HMP Exhibit and a receiving channel identification name or number
correlating to the project's HMP Exhibit.
Has a geomorphic assessment been performed for the receiving channel(s)?
No, the low flow threshold is 0.1Q2 (default low flow threshold)
Yes, the result is the low flow threshold is 0.1Q2
Yes, the result is the low flow threshold is 0.3Q2
Yes, the result is the low flow threshold is 0.5Q2
If a geomorphic assessment has been performed, provide title, date, and preparer:
Discussion / Additional Information: (optional)
Other Site Requirements and Constraints
When applicable, list other site requirements or constraints that will influence storm water
management design, such as zoning requirements including setbacks and open space, or City
codes governing minimum street width, sidewalk construction, allowable pavement types, and
drainage requirements.
Optional Additional Information or Continuation of Previous Sections As Needed
This space provided for additional information or continuation of information from previous
sections as needed.
Other: infeasible to do so.
C. X BMPs for Rooftop Areas: Check this box if rooftop areas are proposed and select at least one BMP
below.
If no BMPs are selected, explain why they are infeasible in the area below.
(see Fact
Sheet BL-3)
X SD-B
Direct runoff to pervious areas
SD-C
Install green roofs
SD-E
Install rain barrels
D. BMPs for Landscaped Areas: Check this box if landscaping is proposed and select the BMP below
X SD-K Sustainable Landscaping
If SD-K is not selected, explain why it is infeasible in the area below.
(see Fact
Sheet BL-4)
Provide discussion/justification for site design BMPs that will not be implemented (either partially or fully):
Baseline BMPs for Pollutant-generating Sources
All development projects must complete Table 2 - Source Control Requirement to identify applicable requirements for
documenting pollutant-generating sources/ features and source control BMPs.
BMPs must be implemented for source control features where feasible. Leaving the box for a BMP unchecked means it
will not be implemented (either partially or fully) either because it is inapplicable or infeasible. Explanations must be
provided in the area below. The table provides specific instructions on when explanations are required.
Table 2 - Source Control Requirement
A. Management of Storm Water Discharges
1. Identify all proposed outdoor
work areas below
Check here if none are proposed
2. Which BMPs will be used to prevent
materials from contacting rainfall or
runoff?
(See Fact Sheet BL-5)
Select all feasible BMPs for each work area
3. Where will runoff from the
work area be routed?
(See Fact Sheet BL-6)
Select one or more option for each
work area
SC-A
Overhead
covering
SC-B
Separation
flows from
adjacent
areas
SC-C
Wind
protection
SC-D
Sanitary
sewer
SC-E
Containment
system
Other
x Trash & Refuse Storage
x Materials & Equipment Storage X X
E-36 Page 2 of 4 Revised 02/22
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Loading & unloading
Fueling
Maintenance & Repair
Vehicle & Equipment Cleaning
Other:
B. Management of Storm Water Discharges (see Fact Sheet BL-7)
Select one option for each feature below:
• Storm drain inlets and catch basins … are not proposed X will be labeled with stenciling or signage to
discourage dumping (SC-F)
• Interior work surfaces, floor drains &
sumps …
are not proposed X will not discharge directly or indirectly to the MS4
or receiving waters
• Drain lines (e.g. air conditioning, boiler,
etc.) …
are not proposed X will not discharge directly or indirectly to the MS4
or receiving waters
• Fire sprinkler test water … are not proposed X will not discharge directly or indirectly to the MS4
or receiving waters
Provide discussion/justification for source control BMPs that will not be implemented (either partially or fully):
E-36 Page 3 of 4 Revised 02/22
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Form Certification
This E-36 Form is intended to comply with applicable requirements of the city’s BMP Design Manual. I certify that it has
been completed to the best of my ability and accurately reflects the project being proposed and the applicable BMPs
proposed to minimize the potentially negative impacts of this project's land development activities on water quality. I
understand and acknowledge that the review of this form by City staff is confined to a review and does not relieve me as
the person in charge of overseeing the selection and design of storm water BMPs for this project, of my responsibilities for
project design.
Preparer Signature: Date: 01-19-2024
Print preparer name: Hector Maytorena
E-36 Page 4 of 4 Revised 02/22
k-7-,//2-:1" I 1/"':Z/
~
SUMMARY OF PDP STRUCTURAL BMPS
PDP Structural BMPs
All PDPs must implement structural BMPs for storm water pollutant control (see Chapter 5 of the
BMP Design Manual). Selection of PDP structural BMPs for storm water pollutant control must
be based on the selection process described in Chapter 5. PDPs subject to hydromodification
management requirements must also implement structural BMPs for flow control for
hydromodification management (see Chapter 6 of the BMP Design Manual). PDP’s subject to
trash capture requirements must implement trash capture devices (see Chapter 4 of the BMP
Design Manual). Storm water pollutant control, flow control for hydromodification management
and trash capture can all be achieved within the same structural BMP(s).
PDP structural BMPs must be verified by the City at the completion of construction. This may
include requiring the project owner or project owner's representative to certify construction of the
structural BMPs (see Section 1.12 of the BMP Design Manual). PDP structural BMPs must be
maintained into perpetuity, and the City must confirm the maintenance (see Section 7 of the BMP
Design Manual).
Use this form to provide narrative description of the general strategy for structural BMP
implementation at the project site in the box below. Then complete the PDP structural BMP
summary information sheet for each structural BMP within the project (copy the BMP summary
information page as many times as needed to provide summary information for each individual
structural BMP).
Describe the general strategy for structural BMP implementation at the site. This information must
describe how the steps for selecting and designing storm water pollutant control BMPs presented
in Section 5.1 of the BMP Design Manual were followed, and the results (type of BMPs selected).
For projects requiring hydromodification flow control BMPs and trash capture devices, indicate
whether pollutant control, trash capture and flow control BMPs are integrated together or
separate.
The DCV was determined for each DMA (calculations provided in Worksheet B.1). Site design
BMPs are considered in the design to the maximum extent feasible. Harvest and use was
deemed to be infeasible due to insufficient demand for reuse through landscape and toilet
flushing. An infiltration analysis was completed and the site was determined to fall under partial
infiltration condition. As part of the infiltration analysis, the geotechnical report provided guidance
that infiltration is not recommended within 10 feet of proposed structures. For this site, at least
85% of the site falls within this area, limiting areas for proposed retention BMPs (refer to
infiltration infeasibility study exhibit for details). Due to site constraints, five compact biofiltration
basins (Modular Wetland Systems) are proposed to comply with the pollutant control
requirements. Unlined permeable pavers in DMA B-3 and B-4 will provide sufficient volume
retention for the entire site.
Target retention volume is determined to be 82 cf assuming restricted infiltration BMP. The
volume retention is provided within the permeable pavement located outside the 10’ infiltration
buffer from the structure. A total permeable pavement area of 167 sf is considered for volume
retention (refer to infiltration infeasibility study exhibit for details). Calculations provided in City of
San Diego Worksheet B.5-6.
The project site is not required to comply with trash capture requirements. The project site is
designated as R-15 per City of Carlsbad Land Use Map, residential 8-15 du/ac which is not listed
under Section 4.4.2.2 of the BMP Manual that requires installation of trash capture BMPs. The
site is exempt from hydromodification flow controls per San Diego County Regional WMAA Map.
[Continued on next page.]
[Continued from previous page. ]
On-site peak flow rate control BMPs are not proposed. A previously constructed off-site 18” pipe
detention system within Ocean Street Right of Way provides peak flow rate mitigation for the site.
This detention system was constructed as part of the Ocean Estates properties project and is
verified from the City of Carlsbad as-built drawing no. #432-3. Additional information and analysis
is provided in the Drainage Report.
Offsite Improvements: A total of 6,261 sf offsite area is proposed to be installed/replaced within
the public right-of-way of Ocean Street, Beech Avenue and Garfield Street. DMAs Off-1, 2 3 & 4
are identified as offsite DMAs in the BMP exhibit. Although improvements are proposed in three
different locations runoff from these DMAs ultimately drains to same discharge point downstream.
Therefore, single BMP (tree well #1) is designed in lieu of separate smaller BMPs for each DMA.
BMP is designed to treat runoff from equal amount of impervious area that is proposed to be
replaced/installed within the public right-of-way areas.
DMA B-2 is shown to be de-minimis with an impervious area of 225 sf.
An on-site tree well is proposed for pollution control in DMA B-1 shown on the DMA Exhibit.
Green street design standards are implemented for the design of pollutant control BMP situated
within the public right-of-way. A tree well is proposed to be installed on Beech Avenue for this
purpose. Both tree wells are lined on the sides. On-site Tree Well #2 contains a subdrain per
geotechnical recommendations. Calculation of soil volume required for proposed tree wells BMP
is summarized below;
Off-site Tree Well #1:
Total area disturbed = 6,261 sf
Impervious area = 4,844 sf
Pervious Area = 1,417 sf
Effective Impervious Area = 4,986 sf
Min. Soil Vol. Required = 982 cf, Provided Soil Volume = 1,008 cf
See Worksheet I-3: Step 3. Tree Well Sizing in this report for
Minimum Soil Volume Calculations
On-site Tree Well #2:
Total area disturbed = 446 sf
Impervious area = 358 sf
Pervious Area = 88 sf
Effective Impervious Area = 500 sf
Min. Soil Vol. Required = 157 cf, Provided Soil Volume = 192 cf
See Worksheet I-3: Step 3. Tree Well Sizing in this report for
Minimum Soil Volume Calculations
Structural BMP Summary Information
[Copy this page as needed to provide information for each individual proposed
structural BMP]
Structural BMP ID No. BMP #1 MWS-L-4-4
DWG Sheet No.
Type of structural BMP:
Retention by harvest and use (HU-1)
Retention by infiltration basin (INF-1)
Retention by bioretention (INF-2)
Retention by permeable pavement (INF-3)
Dry Wells (INF-4)
Partial retention by biofiltration with partial retention (PR-1) Biofiltration (BF-1)
X Proprietary Biofiltration (BF-3)
Flow-thru treatment control included as pre-treatment/forebay for an onsite retention or
biofiltration BMP (provide BMP type/description and indicate which onsite retention or
biofiltration BMP it serves in discussion section below)
Detention pond or vault for hydromodification management
Trash capture device
Other (describe in discussion section below)
Purpose:
X Pollutant control only
Hydromodification control only
Combined pollutant control and hydromodification control
Pre-treatment/forebay for another structural BMP
Trash Capture
Other (describe in discussion section below)
Discussion (as needed):
Structural BMP Summary Information
[Copy this page as needed to provide information for each individual proposed
structural BMP]
Structural BMP ID No. BMP #2 MWS-L-4-4
DWG Sheet No.
Type of structural BMP:
Retention by harvest and use (HU-1)
Retention by infiltration basin (INF-1)
Retention by bioretention (INF-2)
Retention by permeable pavement (INF-3)
Dry Wells (INF-4)
Partial retention by biofiltration with partial retention (PR-1) Biofiltration (BF-1)
X Proprietary Biofiltration (BF-3)
Flow-thru treatment control included as pre-treatment/forebay for an onsite retention or
biofiltration BMP (provide BMP type/description and indicate which onsite retention or
biofiltration BMP it serves in discussion section below)
Detention pond or vault for hydromodification management
Trash capture device
Other (describe in discussion section below)
Purpose:
X Pollutant control only
Hydromodification control only
Combined pollutant control and hydromodification control
Pre-treatment/forebay for another structural BMP
Trash Capture
Other (describe in discussion section below)
Discussion (as needed):
Structural BMP Summary Information
[Copy this page as needed to provide information for each individual proposed
structural BMP]
Structural BMP ID No. BMP #3 MWS-L-4-4
DWG Sheet No.
Type of structural BMP:
Retention by harvest and use (HU-1)
Retention by infiltration basin (INF-1)
Retention by bioretention (INF-2)
Retention by permeable pavement (INF-3)
Dry Wells (INF-4)
Partial retention by biofiltration with partial retention (PR-1) Biofiltration (BF-1)
X Proprietary Biofiltration (BF-3)
Flow-thru treatment control included as pre-treatment/forebay for an onsite retention or
biofiltration BMP (provide BMP type/description and indicate which onsite retention or
biofiltration BMP it serves in discussion section below)
Detention pond or vault for hydromodification management
Trash capture device
Other (describe in discussion section below)
Purpose:
X Pollutant control only
Hydromodification control only
Combined pollutant control and hydromodification control
Pre-treatment/forebay for another structural BMP
Trash Capture
Other (describe in discussion section below)
Discussion (as needed):
Structural BMP Summary Information
[Copy this page as needed to provide information for each individual proposed
structural BMP]
Structural BMP ID No. BMP #4 MWS-L-4-4
DWG Sheet No.
Type of structural BMP:
Retention by harvest and use (HU-1)
Retention by infiltration basin (INF-1)
Retention by bioretention (INF-2)
Retention by permeable pavement (INF-3)
Dry Wells (INF-4)
Partial retention by biofiltration with partial retention (PR-1) Biofiltration (BF-1)
X Proprietary Biofiltration (BF-3)
Flow-thru treatment control included as pre-treatment/forebay for an onsite retention or
biofiltration BMP (provide BMP type/description and indicate which onsite retention or
biofiltration BMP it serves in discussion section below)
Detention pond or vault for hydromodification management
Trash capture device
Other (describe in discussion section below)
Purpose:
X Pollutant control only
Hydromodification control only
Combined pollutant control and hydromodification control
Pre-treatment/forebay for another structural BMP
Trash Capture
Other (describe in discussion section below)
Discussion (as needed):
Structural BMP Summary Information
[Copy this page as needed to provide information for each individual proposed
structural BMP]
Structural BMP ID No. BMP #5 MWS-L-4-4
DWG Sheet No.
Type of structural BMP:
Retention by harvest and use (HU-1)
Retention by infiltration basin (INF-1)
Retention by bioretention (INF-2)
Retention by permeable pavement (INF-3)
Dry Wells (INF-4)
Partial retention by biofiltration with partial retention (PR-1) Biofiltration (BF-1)
X Proprietary Biofiltration (BF-3)
Flow-thru treatment control included as pre-treatment/forebay for an onsite retention or
biofiltration BMP (provide BMP type/description and indicate which onsite retention or
biofiltration BMP it serves in discussion section below)
Detention pond or vault for hydromodification management
Trash capture device
Other (describe in discussion section below)
Purpose:
X Pollutant control only
Hydromodification control only
Combined pollutant control and hydromodification control
Pre-treatment/forebay for another structural BMP
Trash Capture
Other (describe in discussion section below)
Discussion (as needed):
Structural BMP Summary Information
[Copy this page as needed to provide information for each individual proposed
structural BMP]
Structural BMP ID No. BMP #6 Permeable Pavers
DWG Sheet No.
Type of structural BMP:
Retention by harvest and use (HU-1)
Retention by infiltration basin (INF-1)
Retention by bioretention (INF-2)
X Retention by permeable pavement (INF-3)
Dry Wells (INF-4)
Partial retention by biofiltration with partial retention (PR-1) Biofiltration (BF-1)
Proprietary Biofiltration (BF-3)
Flow-thru treatment control included as pre-treatment/forebay for an onsite retention or
biofiltration BMP (provide BMP type/description and indicate which onsite retention or
biofiltration BMP it serves in discussion section below)
Detention pond or vault for hydromodification management
Trash capture device
Other (describe in discussion section below)
Purpose:
X Pollutant control only
Hydromodification control only
Combined pollutant control and hydromodification control
Pre-treatment/forebay for another structural BMP
Trash Capture
Other (describe in discussion section below)
Discussion (as needed):
478 SF Total, 81 SF without Impermeable Liner underneath.
Permeable Pavers do not meet criteria for SD-D Site Design BMPs due to the impermeable liner
underneath the majority of the permeable pavers (See detail on DMA exhibit). The entire
permeable paver area is hydraulically connected via the aggregate layer. The entire volume
stored underneath the underdrain will infiltrate through the area of permeable pavers that does
not contain the impermeable liner. See INF-3 calculations that show that there is sufficient area
and infiltration rate to infiltrate this volume. The volume infiltrated is larger than the required DCV
for the permeable pavers and provides additional volume retention for the site.
Structural BMP Summary Information
[Copy this page as needed to provide information for each individual proposed
structural BMP]
Structural BMP ID No. BMP #7 Permeable Pavers
DWG Sheet No.
Type of structural BMP:
Retention by harvest and use (HU-1)
Retention by infiltration basin (INF-1)
Retention by bioretention (INF-2)
X Retention by permeable pavement (INF-3)
Dry Wells (INF-4)
Partial retention by biofiltration with partial retention (PR-1) Biofiltration (BF-1)
Proprietary Biofiltration (BF-3)
Flow-thru treatment control included as pre-treatment/forebay for an onsite retention or
biofiltration BMP (provide BMP type/description and indicate which onsite retention or
biofiltration BMP it serves in discussion section below)
Detention pond or vault for hydromodification management
Trash capture device
Other (describe in discussion section below)
Purpose:
X Pollutant control only
Hydromodification control only
Combined pollutant control and hydromodification control
Pre-treatment/forebay for another structural BMP
Trash Capture
Other (describe in discussion section below)
Discussion (as needed): 394 SF Total, 84 SF without Impermeable Liner underneath.
Permeable Pavers do not meet criteria for SD-D Site Design BMPs due to the impermeable liner
underneath the majority of the permeable pavers (See detail on DMA exhibit). The entire
permeable paver area is hydraulically connected via the aggregate layer. The entire volume
stored underneath the underdrain will infiltrate through the area of permeable pavers that does
not contain the impermeable liner. See INF-3 calculations that show that there is sufficient area
and infiltration rate to infiltrate this volume. The volume infiltrated is larger than the required DCV
for the permeable pavers and provides additional volume retention for the site.
Structural BMP Summary Information
[Copy this page as needed to provide information for each individual proposed
structural BMP]
Structural BMP ID Off-site Street Tree #1 (Corner of Beech Avenue and Ocean Street)
DWG Sheet No.
Type of structural BMP:
Retention by harvest and use (HU-1)
Retention by infiltration basin (INF-1)
Retention by bioretention (INF-2)
Retention by permeable pavement (INF-3)
Dry Wells (INF-4)
Partial retention by biofiltration with partial retention (PR-1) Biofiltration (BF-1)
Proprietary Biofiltration (BF-3)
Flow-thru treatment control included as pre-treatment/forebay for an onsite retention or
biofiltration BMP (provide BMP type/description and indicate which onsite retention or
biofiltration BMP it serves in discussion section below)
Detention pond or vault for hydromodification management
Trash capture device
X Other (describe in discussion section below)
Purpose:
X Pollutant control only
Hydromodification control only
Combined pollutant control and hydromodification control
Pre-treatment/forebay for another structural BMP
Trash Capture
Other (describe in discussion section below)
Discussion (as needed):
Off-site street tree provided for pollutant control purposes and designed for compliance with
County of San Diego Green Street Standards.Curb inlet to Tree Well #1 sized to fully capture
diversion flow rate for offline pollutant control BMP per County of San Diego BMP Design Manual
(0.025 cfs). See calculations on Tree Well Exhibit and Worksheet I-3 (Offsite) in Attachment 1E –
Pollutant Control Sizing.
TOTAL DISTURBED TOTAL
(SF)
IMPERVIOUS
(SF)
PERVIOUS
(SF)
OFF-1 2309 2309 0
OFF-2 1512 1512 0
OFF-3 1015 426 589
OFF-4 1425 597 828
TOTAL 6261 4844 1417
DRAINAGE AREA
TREATED BY TREE
WELL #1
TOTAL
(SF)
IMPERVIOUS
(SF)
PERVIOUS
(SF)
EXCESS OFF-SITE
AREA
5490 5490 0
OFF-3 1015 426 589
TOTAL TO TREE
WELL
6505 5916 589
Structural BMP Summary Information
[Copy this page as needed to provide information for each individual proposed
structural BMP]
Structural BMP ID On-site Street Tree #2 (Located within DMA B-1)
DWG Sheet No.
Type of structural BMP:
Retention by harvest and use (HU-1)
Retention by infiltration basin (INF-1)
Retention by bioretention (INF-2)
Retention by permeable pavement (INF-3)
Dry Wells (INF-4)
Partial retention by biofiltration with partial retention (PR-1) Biofiltration (BF-1)
Proprietary Biofiltration (BF-3)
Flow-thru treatment control included as pre-treatment/forebay for an onsite retention or
biofiltration BMP (provide BMP type/description and indicate which onsite retention or
biofiltration BMP it serves in discussion section below)
Detention pond or vault for hydromodification management
Trash capture device
X Other (describe in discussion section below)
Purpose:
X Pollutant control only
Hydromodification control only
Combined pollutant control and hydromodification control
Pre-treatment/forebay for another structural BMP
Trash Capture
Other (describe in discussion section below)
Discussion (as needed):
On-site street tree provided for pollutant control purposes. See calculations on Tree Well Exhibit
and Worksheet I-3 (Offsite) in Attachment 1E – Pollutant Control Sizing.
ATTACHMENT 1
BACKUP FOR PDP POLLUTANT CONTROL BMPS
This is the cover sheet for Attachment 1.
Check which Items are Included behind this cover sheet:
Attachment
Sequence
Contents Checklist
Attachment 1a DMA Exhibit (Required)
See DMA Exhibit Checklist on the back of this
Attachment cover sheet. (24”x36” Exhibit
typically required)
X Included
Attachment 1b Tabular Summary of DMAs Showing DMA ID
matching DMA Exhibit, DMA Area, and DMA
Type (Required)*
*Provide table in this Attachment OR on DMA
Exhibit in Attachment 1a
X Included on DMA
Exhibit in Attachment
1a
Included as
Attachment 1b,
separate from DMA
Exhibit
Attachment 1c Form K-7, Harvest and Use Feasibility Screening
Checklist (Required unless the entire project will
use infiltration BMPs)
Refer to Appendix B of the BMP Design Manual
to complete Form K-7.
X Included
Not included because
the entire project will
use infiltration BMPs
Attachment 1d Infiltration Feasibility Analysis (Required unless
the project will use harvest and use BMPs)
Refer to Appendix D of the BMP Design Manual.
X Included
Not included because
the entire project will
use harvest and use
BMPs
Attachment 1e Pollutant Control BMP Design Worksheets /
Calculations (Required)
Refer to Appendices B, E, and I of the BMP
Design Manual for structural pollutant control and
significant site design BMP design guidelines
X Included
Attachment 1f Trash Capture BMP Design Calculations
Refer to Appendices J of the BMP Design Manual
for Trash capture BMP design guidelines
Included
X Not included because
the entire project is not
subject to trash capture
requirements
Use this checklist to ensure the required information has been included on the DMA
Exhibit:
The DMA Exhibit must identify:
X Underlying hydrologic soil group
X Approximate depth to groundwater
X Existing natural hydrologic features (watercourses, seeps, springs, wetlands) X X
X Critical coarse sediment yield areas to be protected (if present)
X Existing topography and impervious areas
X Existing and proposed site drainage network and connections to drainage offsite
X Proposed grading
X Proposed impervious features
X Proposed design features and surface treatments used to minimize imperviousness
X Drainage management area (DMA) boundaries, DMA ID numbers, and DMA areas (square
footage or acreage), and DMA type (i.e., drains to BMP, self-retaining, or self-mitigating)
X Structural BMPs (identify location and type of BMP)
X Tabular DMA Summary
SD SD SDSDSDSD
SD
SD
SD
SD
SD
SD
SD
SD
SD SD SD SD SD
S
D
SD
SD SD SD SD SD SD SD
SD
SD
SD
SD
SD
SD
S
D
S S S S S S S S S S S S S S S
S S S S S S S S S S S S S S S
W W W W W W W W W W W W W WW
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43
9449 BALBOA AVE, STE 270
SAN DIEGO, CA 92123 619.299.5550BWE JOB NO. 13913US1.00
SD
ENGINEERING DEPARTMENT
2710, 2720, 2730, & 2740 OCEAN STREET
CARLSBAD, CA. 92008
SITE DESIGN BMPS:
SOURCE CONTROL BMPS:
LEVEL 1
GARAGE
PERMEABLE PAVEMENT & LINER DETAILNOT TO SCALE
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Area (acres) Impervious Ar ea (acres} %Imp HSG Area Weighted Runoff Coefficient (C) DCV (cubic feet) Mitigated By (BM PI D) Pollutant Control Type Drainsto(POCID)
0.053 0.052 99.3% B 0.894 103 BMP#3 BF-3 Proprietary Biofiltration 1
0.082 0.074 90.2% B 0.822 150 4 BF-3 Proprietary Biofiltration 1
0.034 0.024 70.6% B 0.665 49
0.136 0.136 99.7% B 0.898 267 BMP#2
0.083 0.074 89.2% B 0.813 148 BM P# 1
0.049 0.049 100.0% B 0.900 96 BMP#5
0.130 0.082 63.1% B 0.605 175 BMP#5
0.010 0.008 82.2% B 0.757 17 TreeWell#2
0.005 0.005 100.0% B 0.900 De-minimis
0.019 0.014 73.8% B 0.690 29 6
0.017 0.010 61.4% B 0.591 22
0.618 0.529 85.6% B 0.785 1,056
0.053 0.053 100.0% B 0.900 104
0.035 0.035 100.0% B 0.900 68
BF-3 Proprietary Biofiltration 1
BF-3 Proprietary Biofiltration 1
BF-3 Proprietary Biofiltration 1
BF-3 Proprietary Biofiltration 1
BF-3 Proprietary Biofiltration 1
Other 1
De-minim is 1
I NF-3 Pervious Pavers 1
I NF-3 Pervious Pavers 1
1
SSD-BM P Tree Wei I # 1 1
SSD-BM P Tree Wei I # 1 1 5 0 10
~-✓ ~ /,__,
B\V E
20 CIVIL •STRUCTURAL•SURVEY• PLANNING
0.023 0.010 42.0% B 0.436 22
0.033 0.014 41.9% B 0.435 31 SSD-BM P Tree Wei I # 1
SSD-BM P Tree Wei I # 1 1
1 SCALE IN FEET
1 inch = 10 ft.
DATE IN\TlAL
ENGINEER OF WORK
0.144 0.111 77.4% B 0.719 225 1
CT 2022-0003/CUP 2022-0014/CDP 2022-0047 (DEV2022-0063)
PARTY RESPONSIBI E FOR MAINTENANCE
jY ., NAME FRONT PORCH COMMUNITIES
~:£._ADDRESS BOO NORTH BRAND BLVD. CONTACT JOAN JOHNSON
191H FLOOR
BMP CONSTRUCTION AND
INSPECTION NOTES
GLENDALE, CA 92103
PHONE NO .. ~m~o _____ _
PLAN PREPARED BY:
NAME HECTOR MAYTORENA
COMPANY_,,B,,,WE..._.l...,NC..._ ___ _
ADDRESS 2449 BALBOA AVENUE
SUIJE 270
SAN DIEGO, CA 92123
PHONE NO. 619 299 5550
BMP NOTES
SIGNATURE
CERTIFlCA TION RCE 86216
1. THESE BMPS ARE MANDATORY TO BE INSTALLED PER
MANUFACTURER'S RECOMMENDATIONS OR lHESE PLANS.
lHE EOW WILL VERIFY THAT PERMANENT BMPS ARE
CONSTRUCTED AND OPERA TING IN COMPLIANCE 1'111H THE
APPLICABLE REQUIREMENTS. PRIOR TO OCCUPANCY THE EOW
MUST PROVIDE:
1. PHOTOGRAPHS OF lHE INSTALLATION OF PERMANENT
BMPS PRIOR TO CONSTRUCTION, DURING CONSTRUCTION,
AND AT FINAL INSTALLATION.
2. A WET STAMPED LETlER VERIFYING THAT PERMANENT
BMPS ARE CONSTRUCTED AND OPERATING PER lHE
REQUIREMENTS OF THE APPROVED PLANS.
3. PHOTOGRAPHS TO VERIFY lHAT PERMANENT WA lER
QUALITY TREAlMENT SIGNAGE HAS BEEN INSTALLED.
PRIOR TO RELEASE OF SECURITIES, THE DEVELOPER IS
RESPONSIBLE FOR ENSURING lHE PERMANENT BMPS HA VE NOT
BEEN REMOVED OR MODIFIED BY lHE NEW HOMEOWNER OR HOA
WllHOUT THE APPROVAL OF THE CITY ENGINEER.
LEGEND SYMBOL
EXISTING BUILI 2. NO CHANGES TO lHE PROPOSED BMPS ON lHIS SHEET
WITHOUT PRIOR APPROVAL FROM lHE CITY ENGINEER. PROPERTY LINE/RIGHT-OF-WAY
CENTER LINE
-ROW - - -P/L---C/L-----
GU Q c"
3. NO SUBSTITUTIONS TO THE MA TERI AL OR TYPES OR
PLANTING TYPES WllHOUT PRIOR APPROVAL FROM lHE CITY
ENGINEER.
4. NO OCCUPANCY WILL BE GRANTED UNTIL lHE CITY
INSPECTION STAFF HAS INSPEClED THIS PROJECT FOR
APPROPRIAlE BMP CONSTRUCTION AND INSTALLATION.
5. REFER TO MAINTENANCE AGREEMENT DOCUMENT.
6. SEE PROJECT SWMP FOR ADDlllONAL INFORMATION.
@ OVERHEAD COVERING
-MA lERIALS & EQUIPMENT STORAGE
@ SEPARATION FLOWS FROM ADJACENT AREAS
-MAlERIALS & EQUIPMENT STORAGE
STORM DRAINS AND CATCH BASINS
1'11LL BE LABELED 1'11TH STENCILING
OR SIGNAGE TO DISCOURAGE
DUMPING
! SD-B ! DIRECT RUNOFF TO PERVIOUS AREAS
-SIDEWALKS & WALKWAYS
-DRII/EWA YS
-PATIOS, DECKS, & COURTYARDS
-ROOFTOP AREAS
! SD-I ! CONSTRUCT SURFACES FROM PERMEABLE MATERIALS
-PARKING AREAS & WALKWAYS
-PATIOS, DECKS, & COURTYARDS
! SD-K ! SUSTAINABLE LANDSCAPING
STRUCllJRAL BMP KEYNOTES
VCOMPACT PROPRIETARY BIOFILTRATION BMP (POLLUTANT CONTROL)
~PERMEABLE PAVEMENT BMP (POLLUTANT CONTROL)
SWOMP NOTES
1. lHE SITE IS COMPRISED OF HYDROLOGIC
SOIL TYPE B.
2. APPROXIMATE DEPlH TO GROUNDWATER
GREA lER THAN 30 FEET
EXISTING NA TUR AL HYDROLOGIC FEATURES
-NOT APPLICABLE
NO CRlllCAL COARSE SEDIMENT YIELD
AREAS ARE NOT PRESENT ON SITE
PROJECT DISCHARGES DIRECll Y INTO
HARDENED CONVEYANCE AND ROUlED
DIRECll Y TO THE PACIFIC OCEAN.
PROJECT IS HYDROMODIFICA TION EXEMPT.
NOTES:
PROPOSED
BUILDING/
STRUCTURE
SUBGRADE
AC PAVEMENT
AC PAVEMENT GRIND & OVERLAY
CONCRElE PAVEMENT
PAYERS
NEW CATCH BASIN SIZE PER PLAN
NEW AREA DRAIN
NEW ROOF DRAIN PER PLUMBING PLAN
NEW SEWER/STORM DRAIN CLEANOUT
SllE WALL I I I I I I I I I
STORM DRAIN
MODULAR WETLAND
12" TRENCH DRAIN
STORM DRAIN CLEANOUT TYPE A4
STREET TREE BOX
SUMP PUMP
ROOF DRAIN DAYLIGHTS TO
BMP PER PLUMBING PLANS
□
[Q]
PERMEABLE PA VERS 11 I I I I I I ~
PROJECT OUlER DMA BOUNDARY
DMA BOUNDARY
EXISTING CONTOUR
NEW CONTOUR
FLOW DIRECTION
FLOW PATH
POINT OF COMPLIANCE (POC)
DRAINAGE MANAGEMENT AREA MARKER
& AREA (AC)
10-FEET BUFFER FROM
UNDERGROUND STRUCTURE
\\1-IERE INFlL TRA TION IS NOT
RECOMMENDED PER
GEOTECHNICAL REPORT
CONCRETE PAVER BAND
PER LANDSCAPE PLAN
4" THICK CONCRETE
PA VER BLOCK PER
LANDSCAPE PLAN
------------xxx ----------------------xxx __ __
---xxx ..
--+➔➔➔➔-
ffi
~ ~
6" ASTM #2 AGGREGATE
3" ABOVE BOTTOM
4" DIA PERFORATED SUBDRAIN. PERFORATED HOLES
3/8" f MIN @ 3-1/4" SPACING ALONG PIPE,
W/ STAGGERED HORIZONTAL ROWS. PER CITY OF SAN
DIEGO STANDARD DRAWING SDSW-102.
1. ALL STONE LAYERS MUST BE CLEAN AND FREE OF FINE GRANULAR MATERIAL
DATE IN\TlAL
2. PERVIOUS CONCREIE AND/OR PAVERS SHALL BE INSTALLED PER MANUFACTURER
SPECIFICATIONS.
DMA EXHIBIT
[2]1 CITY OF CARLSBAD I[!]
FRONT PORCH MEMORY CAFE AND IIIDEPENDENT LIVING
DMA/SINGLE SHEET BMP SITE PLAN
DATE INITIAL
REVISION DESCRIPTION OTHER APPROVAL CITY APPROVAL
SD
W
W
W
S
S
S
S
S S SS
OHE
OHE
OHE
OH
E
OH
E
OH
E
OH
E
OH
E
OHE OHE OHE
W W
W
W
W
W
S
S
S
S
S
S
S
S
S
S
S
W
W
W
W
W
W
W
S S S
W
51
9449 BALBOA AVE, STE 270
SAN DIEGO, CA 92123 619.299.5550BWE JOB NO. 13913US1.00
ENGINEERING DEPARTMENT
2710, 2720, 2730, & 2740 OCEAN STREET
CARLSBAD, CA. 92008
SITE DESIGN BMPS:
SOURCE CONTROL BMPS:
LEVEL 1
GARAGE
PERMEABLE PAVEMENT & LINER DETAILNOT TO SCALE
MATCHLINE SHEET 1
MA
T
C
H
L
I
N
E
S
H
E
E
T
1
SD
n
2
C
I
L
=
0
C
c:
CJ n
C u
C' ,c
Q_
I
I
I
I
I
I
I
I
I
I
I
I
I
I I
I
I< ~~-
~ ~~-..
:,: a. "' <
MH
3.9
.3
I
I
I
I
I
I
I
I
I
I
I
SMH • .6
I
I
I
I
I ~I I
~=-i~+-«>
52 CONC
ENCASED
I< SWR ~,-..
~'? ..
~ ,..,
~
REQUIRED IMPERVIOUS AREA = OFF-1 + OFF-2 + OFF-4 = 0.053 + 0.035 + 0.014 = 0.102 ACRE = 4,418 SF
EXCESS IMPERVIOUS AREA = 5,490 SF
I 5,490 SF > 4,418 SF
I
qi'? ..
pp
'\ ~~-..
R DWG 195-
I
. I
I ~"""' • • ' "
!;" s
.. .• I , . , .
I ... -..
,.,,1,1..:1
.. DMA Unique Identifier Area (acres)
A-1 0.053
A-2 0.082
A-3 0.034
A-4 0.136
A-5 0.083
A-6 0.049
A-7 0.130
B-1 0.010
8-2 0.005
8-3 0.019
8-4 0.017
TOTAL 0.618
OFF-1 0.053
OFF-2 0.035
OFF-3 0.054
OFF-4 0.042
TOTAL OFFSITE 0.184
Tabular Summary of DMAs I Worksheet B-1
Im per vi ous Area (acres) %Imp HSG Area Weighted Runoff Coefficient (C) DCV (cubic feet) Mitigated By (BM PI D) Pollutant Control Type
0.052 99.3% B 0.894 103 BMP#3 BF-3 Proprietary Biofiltration
0.074 90.2% B 0.822 150 BMP#4 BF-3 Proprietary Biofiltration
0.024 70.6% B 0.665 49 BMP#2 BF-3 Proprietary Biofiltration
0.136 99.7% B 0.898 267 01v1t-'ll'2 BF-3 Proprietary Biofiltration
0.074 89.2% B 0.813 148 BM P# 1 BF-3 Proprietary Biofiltration
0.049 100.0% B 0.900 96 BMP#5 BF-3 Proprietary Biofiltration
0.082 63.1% B 0.605 175 BMP#5 BF-3 Proprietary Biofiltration
0.008 82.2% B 0.757 17 TreeWell#2 0th er
0.005 100.0% B 0.900 -De-minimis De-minimis
0.014 73.8% B 0.690 29 BMP#6 I NF-3 Pervious Pavers
0.010 61.4% B 0.591 22 BMP#7 INF-3 Pervious Pavers
0.529 85.6% B 0.785 1,056 --
0.053 100.0% B 0.900 103 -SSD-BM P Tree Wei I # 1
0.035 100.0% B 0.900 68 -SSD-BM P Tree Wei I# 1
0.040 73.8% B 0.690 82 -SSD-BM P Tree Wei I # 1
0.023 55.6% B 0.545 50 -SSD-BM P Tree Wei I # 1
0 .151 82.1% B 0.757 303 --
~-✓ ~ /,__,
5 0 10 B\V E
20 CIVIL •STRUCTURAL•SURVEY• PLANNING
SCALE IN FEET DATE INITIAL
1 inch = 10 ft. ENGINEER OF WORK
Drainsto(POCID)
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
CT 2022-0003/CUP 2022-0014/CDP 2022-0047 (DEV2022-0063)
PARTY RESPONSIBI E FOR MAINTENANCE
NAME FRONT PORCH COMMUNITIES
ADDRESS BOO NORTH BRAND BLVD. CONTACT JOAN JOHNSON
191H FLOOR
GLENDALE, CA 92103
PHONE NO .. ~m~o _____ _
PLAN PREPARED BY:
NAME HECTOR MAYTORENA
COMPANY...,B,,,WE..._.l...,NC..._ ___ _ SIGNATURE
ADDRESS 2449 BALBOA AVENUE
SUIJE 270
SAN DIEGO, CA 92123
PHONE NO. 619 299 5550 CERTIFlCA TION RCE 86216
BMP NOTES
1. THESE BMPS ARE MANDATORY TO BE INSTALLED PER
MANUFACTURER'S RECOMMENDATIONS OR THESE PLANS.
2. NO CHANGES TO THE PROPOSED BMPS ON THIS SHEET
WITHOUT PRIOR APPROVAL FROM THE CITY ENGINEER.
3. NO SUBSTITUTIONS TO THE MA lERIAL OR TYPES OR
PLANTING TYPES 1'11THOUT PRIOR APPROVAL FROM THE CITY
ENGINEER.
4. NO OCCUPANCY 1'11LL BE GRANlED UNTIL THE CITY
INSPECTION STAFF HAS INSPECTED THIS PROJECT FOR
APPROPRIATE BMP CONSTRUCTION AND INSTALLATION.
5. REFER TO MAINTENANCE AGREEMENT DOCUMENT.
6. SEE PROJECT SWMP FOR ADDITIONAL INFORMATION.
@ OVERHEAD COVERING
-MATERIALS & EQUIPMENT STORAGE
@ SEPARATION FLOWS FROM ADJACENT AREAS
-MATERIALS & EQUIPMENT STORAGE
STORM DRAINS AND CATCH BASINS
1'11LL BE LABELED 1'11TH STENCILING
OR SIGNAGE TO DISCOURAGE
DUMPING
! SD-B ! DIRECT RUNOFF TO PERVIOUS AREAS
-SIDEWALKS & WALKWAYS
-DRII/EWA YS
-PATIOS, DECKS, & COURTYARDS
-ROOFTOP AREAS
I SD-I I CONSTRUCT SURFACES FROM PERMEABLE MATERIALS
-PARKING AREAS & WALKWAYS
-PATIOS, DECKS, & COURTYARDS
I SD-KI SUSTAINABLE LANDSCAPING
STRUCTURAL BMP KEYNOlES
VCOMPACT PROPRIETARY BIOFILTRATION BMP (POLLUTANT CONTROL)
V PERMEABLE PAVEMENT BMP (POLLUTANT CONTROL)
SWOMP NOlES
1. THE SllE IS COMPRISED OF HYDROLOGIC
SOIL TYPE B.
2. APPROXIMA 1E DEPTH TO GROUNDWATER
GREATER THAN 30 FEET
3. EXISTING NA TUR AL HYDROLOGIC FEATURES
-NOT APPLICABLE
4. NO CRITICAL COARSE SEDIMENT YIELD
AREAS ARE NOT PRESENT ON SllE
5. PROJECT DISCHARGES DIRECTLY INTO
HARDENED CONVEYANCE AND ROUTED
DIRECTLY TO THE PACIFIC OCEAN.
PROJECT IS HYDROMODIFICA TION EXEMPT.
PROPOSED
BUILDING/
STRUCTURE
BMP CONSTRUCTION AND
INSPECTION NOTES
THE EOW WILL VERIFY THAT PERMANENT BMPS ARE
CONSTRUCTED AND OPERA TING IN COMPLIANCE 1'11TH THE
APPLICABLE REQUIREMENTS. PRIOR TO OCCUPANCY THE EOW
MUST PROVIDE:
1. PHOTOGRAPHS OF THE INSTALLATION OF PERMANENT
BMPS PRIOR TO CONSTRUCTION, DURING CONSTRUCTION,
AND AT FINAL INSTALLATION.
2. A WET STAMPED LETTER VERIFYING THAT PERMANENT
BMPS ARE CONSTRUCTED AND OPERATING PER THE
REQUIREMENTS OF THE APPROVED PLANS.
3. PHOTOGRAPHS TO VERIFY THAT PERMANENT WATER
QUALITY TREATMENT SIGNAGE HAS BEEN INSTALLED.
PRIOR TO RELEASE OF SECURITIES, THE DEVIELOPER IS
RESPONSIBLE FOR ENSURING THE PERMANENT BMPS HA VIE NOT
BEEN REMOVED OR MODIFIED BY THE NEW HOMEOWNER OR HOA
1'11THOUT THE APPROVAL OF THE CITY ENGINEER.
LEGEND SYMBOL
PROPERTY LINE/RIGHT-OF-WAY
CENTER LINE
-ROW - - -P/L---C/L-----
AC PAVIEMENT
AC PAVEMENT GRIND & OVERLAY
CONCRETE PAVIEMENT
PAI/ERS
NEW CATCH BASIN SIZE PER PLAN
NEW AREA DRAIN
NEW ROOF DRAIN PER PLUMBING PLAN
NEW SEWER/STORM DRAIN CLEANOUT
SITE WALL I I I I I I I I I
STORM DRAIN
MODULAR WETLAND
12" TRENCH DRAIN
STORM DRAIN CLEANOUT TYPE A4
STREET TREE BOX
SUMP PUMP
ROOF DRAIN DA YUGHTS TO
BMP PER PLUMBING PLANS
□
[Q]
PERMEABLE PA VERS 11 I I I I I I ~
PROJECT OUTER DMA BOUNDARY
DMA BOUNDARY
EXISTING CONTOUR
NEW CONTOUR
FLOW DIRECTION
FLOW PATH
POINT OF COMPLIANCE (POC)
DRAINAGE MANAGEMENT AREA MARKER
& AREA (AC)
10-FEET BUFFER FROM
UNDERGROUND STRUCTURE
\\1-IERE INFlL TRA TION IS NOT
RECOMMENDED PER
GEOTECHNICAL REPORT
CONCRETE PAVER BAND
PER LANDSCAPE PLAN
4" THICK CONCRETE
PA VER BLOCK PER
LANDSCAPE PLAN
-------------xxx ------------_.,.---------xxx ---xxx ..
-+ ➔ ➔ ➔ ➔ -
ffi
~ X
6" ASTM #2 AGGREGATE
3" ABOVE BOTTOM
4" DIA PERFORATED SUBDRAIN. PERFORATED HOLES
3/8" f MIN @ 3-1/4" SPACING ALONG PIPE,
NOTES: SUBGRADE
W/ STAGGERED HORIZONTAL ROWS. PER CITY OF SAN
DIEGO STANDARD DRAWING SDSW-102.
1. ALL STONE LAYERS MUST BE CLEAN AND FREE OF FINE GRANULAR MATERIAL
DATE INITIAL
2. PERVIOUS CONCRETE AND/OR PAVERS SHALL BE INSTALLED PER MANUFACTURER
SPECIFICATIONS.
DMA EXHIBIT
01 CITY OF CARLSBAD I[!]
FRONT PORCH MEMORY CAFE AND IIIDEPENDENT LIVING
DMA/SINGLE SHEET BMP SITE PLAN
DATE INITIAL
REVISION DESCRIPTION OTHER APPROVAL CITY APPROVAL
SD SD SDSDSDSD
SD
SD
SD
SD
SD
SD
SD
SD
SD SD SD SD SD
S
D
SD
SD SD SD SD SD SD SD
SD
SD
SD
SD
SD
SD
S
D
S S S S S S S S S S S S S S S
S S S S S S S S S S S S S S S
W W W W W W W W W W W W W WW
W
W
W
W
W
W
W
W
W
W
WWWW
SS S
OHE
OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE
OHE
OHE
S
W
W
W
W
W
W
W
W
W
FW
FW
S S
IRRG IRRG IRRG IRRG IRRG IRRG IRRG IRRG
FF 51.75
FF 42.50FF 51.75
FF 42.50
A-5A-5
10
.
0
0
'
10
.
0
0
'
UNDERGROUND PARKING
STRUCTURE BOUNDARY
UNDERGROUND PARKINGSTRUCTURE BOUNDARY
W
W
EC
10-FEET BUFFER FOR
INFILTRATION BMP FROM
UNDERGROUND STRUCTURE
10-FEET BUFFER FORINFILTRATION BMP FROM
UNDERGROUND STRUCTURE
FF 51.75
FF 42.50FF 51.75
FF 42.50
A-5A-5
10
.
0
0
'
10
.
0
0
'
W
W
EC
51
51
51
50
34
35
36
37
38
39
40
41
42
43
9449 BALBOA AVE, STE 270
SAN DIEGO, CA 92123 619.299.5550BWE JOB NO. 13913US1.00
SD
POTENTIAL BIOFILTRATION BASIN #3BOTTOM AREA: 104 SF
ASSUMING 6'' DEEP BASINEXCLUDED BECAUSE BASIN DOES NOTCOMPLY WITH THE REQUIREMENTS OF
STANDARD BIOFILTRATION BMP
POTENTIAL BIOFILTRATION BASIN #4BOTTOM AREA: 58 SFASSUMING 6'' DEEP BASIN
EXCLUDED BECAUSE BASIN DOES NOT COMPLYWITH THE REQUIREMENTS OF STANDARD
BIOFILTRATION BMP
POTENTIAL BIOFILTRATION BASIN #2BOTTOM AREA: 18 SF6" PONDING, 6" FREEBOARD & 3:1 SIDE SLOPES3:1 SLOPE
POTENTIAL BIOFILTRATION BASIN #1BOTTOM AREA: 35 SF6" PONDING, 6" FREEBOARD & 3:1 SIDE SLOPES
BIOFILTRATION INFEASIBILITY STUDYTOTAL SITE AREA = 26,882 SF , EFFECTIVE IMPERVIOUS AREA = 20,467 SF
TOTAL AVAILABLE AREA FOR INFILTRATION BMPS (AREA BETWEEN PL & 10 FEET BUFFER ZONE)* =
2,694 SF (SW OF BUILDING) + 2,755 SF (NE OF BUILDING) = 5,449 SF TOTAL OR ~15% OF THE SITE
REQUIRED BIOFILTRATION AREA = 614 SF (=3% OF EFFECTIVE IMPERVIOUS AREA)
EFFECTIVE BIOFILTRATION AREA = 53 SF (BOTTOM AREA, ASSUMING 6" PONDING, 6" FREEBOARD AND 3:1 SIDE SLOPES
REQUIRED AREA > AVAILABLE AREA
THEREFORE STANDARD BIOFILTRATION IS INFEASIBLE
*RESTRICTIONS WILL APPLY BECAUSE ENTIRE AREA CANNOT BE USED FOR BMPS
VOLUME RETENTION SUMMARY
TARGET RETENTION VOLUME (RESTRICTED CONDITION)= 82 CF (PER SWQMP)
AREA AVAILABLE FOR RETENTION = 165 SF (AREA OUT SIDE OF 10' BUFFER)
RETENTION DEPTH WITHIN GRAVEL STORAGE LAYER;
=82 CF / (165 SF * 0.4) = 1.24 FT = 14.91 INCH
DRAWDOWN TIME = 14.91 IN/ 0.87 IN/HR = 17.14 HOURS ≈ 18 HOURS < 36 HRS (OK)
NOTE: MINIMUM PERVIOUS AREA REQUIRED FOR RETENTION OF 82 CF OF TARGET
VOLUME = 66 SF
INFEASIBILITY STUDY FOR STANDARD BIOFILTRATION BASIN EXHIBIT
81 SF PERMEABLE PAVERS OUTSIDEOF 10-FEET BUFFER
84 SF PERMEABLE PAVERS OUTSIDEOF 10-FEET BUFFER
Jil l I 7)4,( ~W=======
I I .
I
I
I
z z
<( <( ::;; ::;;
"" "" ~ w f-~ ;;::
_J (L
Iii 0 <(
• • 'T <O
---
---
-
z 0 (.)
t
(.) g
' I
I
I
I
I
I
I
I
I
I
F BMP fl IP~RMEABLE ~ -PAVERS {394 SF
8" E.S.V.C.P. SEWER MAIN
TOTAL, 84 SF WITHOUT
IMPERMEABLE LINER).
SEE VOLUME
CALCULATIONS ON
8" SEWER ltj,IJi(t~"~i ~wgr.9
'\ DWG. 188---'9,'--19_3_-_1 __ +----+---
1,_\• ..
~\ ROOF
LINE
TYP
11~
-MINIMIS
OMA
GAR r'Yt Lot-sTR E ET
vy'
DRIVEWAY CONC
~'-
(PRIVATE
BACKYARD
I DRAINS I
I BMP #1
I
I
I< I I< .. I ~-..
I t
I I 03 OOFS ; I
---.. -----------------------------------------------------SUMP PUMP #1: ~-
47
46
I
I
I
I
I
I
I
■
9.60FS -
- -J
I
I
I
I
I
~
I
I
I
I
I
(I)-
--:■--tt+--F==~=t l-•:~ • D:1,0 I ·-·
I
I
I
I
I
I I
• I I
I I
I I
I I
I I IOO.OOFS ;
~
m.,l ,l ·r;,T
---®--i -
I< I ~-..
A-4
.13
// <II])
~
ll==c!,,,=====~ ..
i
I
-1 5
DRAINS TO
BMP /fl
DRIVEi\ Y
EXISTING BUIL1
1 :0% I "~
. I
I
I
5
LEGEND SYMBOL
PROPERTY LINE/RIGHT-OF-WAY -ROW---P/L-
CENTER LINE --C/L-----
AC PAVEMENT
CONCRETE PAVEMENT
NEW CATCH BASIN SIZE PER PLAN
NEW AREA DRAIN
NEW SEWER/STORM DRAIN CLEANOUT
SITE WALL I I I I I I I I I
STORM DRAIN
MODULAR WETLAND
12" TRENCH DRAIN
STORM DRAIN CLIEANOUT TYPE A4
STREET TREE BOX
SUMP PUMP
PERMEABLE PA VERS
PROJECT OUTER DMA BOUNDARY
DMA BOUNDARY
EXISTING CONTOUR
NEW CONTOUR
FLOW DIRECTION
FLOW PATH
POINT OF COMPLIANCE {POC)
DRAINAGE MANAGEMENT AREA MARKER
& AREA (AC)
10-FEET BUFFER FROM
UNDERGROUND STRUCTURE
WHERE INFILTRATION IS NOT
RECOMMENDED PER
GEOTECHNICAL REPORT
UNDERGROUND PARKING
STRUCTURE BOUNDARY
BIOFIL TRA TION BOTTOM
AREA = 53 SF
AREA AVAILABLE BETWEEN PL
AND 10' BUFFER ZONE FOR
INFILTRATION BMP = 5,449 SF
□
[Q]
-----------xxx... ---
-xx)(.____..---xxx~----
------
0 10 B\V E
20 CIVIL•STRUCTURAL•SURVEY•PLANNING
SCALE IN FEET
1 inch = 10 ft.
85th % Rainfall Depth= 0.6 inch
DMA Unique
Identifier Area (acres)Impervious
Area (acres)% Imp HSG
Area Weighted
Runoff Coefficient
(C )
DCV
(cubic feet)Pollutant Control Type Drains to
(POC ID)
A-1 0.053 0.052 99.3% B 0.894 103 BF-3 Proprietary Biofiltration 1
A-2 0.082 0.074 90.2% B 0.822 150 BF-3 Proprietary Biofiltration 1
A-3 0.034 0.024 70.6% B 0.665 49 BF-3 Proprietary Biofiltration 1
A-4 0.136 0.136 99.7% B 0.898 267 BF-3 Proprietary Biofiltration 1
A-5 0.083 0.074 89.2% B 0.813 148 BF-3 Proprietary Biofiltration 1
A-6 0.049 0.049 100.0% B 0.900 96 BF-3 Proprietary Biofiltration 1
A-7 0.130 0.082 63.1% B 0.605 175 BF-3 Proprietary Biofiltration 1
B-1 0.010 0.008 82.2% B 0.757 17 Other 1
B-2 0.005 0.005 100.0% B 0.900 -De-minimis 1
B-3 0.019 0.014 73.8% B 0.690 29 INF-3 Pervious Pavers 1
B-4 0.017 0.010 61.4% B 0.591 22 INF-3 Pervious Pavers 1
Total 0.618 0.529 85.6%B 0.785 1,056 -1
No. of DMAs Total DMA Area
(acres)
Total
Impervious
Area (acres)
% Imp HSG
Area Weighted
Runoff Coefficient
Total DCV
(cubic feet)No. of POCs
9 0.618 0.529 85.6% B 0.785 1,056 1
Where: DMA = Drainage Management Area; Imp = Imperviousness; HSG = Hydrologic Soil Group; DCV= Design Capture Volume; BMP = Best Management
Practice; POC = Point of Compliance; ID = identifier; No. = Number
BMP #6
BMP #7
-
Summary of DMA Information (Must match project description and SWQMP Narrative)
Total Area Treated
(acres)
0.053
BMP #2
BMP #1
BMP #5
BMP #5
Tree Well #2
De-minimis
Tabular Summary of DMAs Worksheet B-1
Mitigated By (BMP
ID)
BMP #3
BMP #4
BMP #2
I
ATTACHMENT 1C – FORM K-7 HARVEST AND USE
Appendix I: Forms and Checklists
Harvest and Use Feasibility Checklist
Form I-7
1. Is there a demand for harvested water (check all that apply) at the project site that is reliably present during
the wet season?
Toilet and urinal flushing
X Landscape irrigation
Other:
2. If there is a demand; estimate the anticipated average wet season demand over a period of 36 hours. Guidance
for planning level demand calculations for toilet/urinal flushing and landscape irrigation is provided in Section
B.3.2.
[Provide a summary of calculations here]
3,652 SF of landscape area has a 36-hour demand of 3 CF.
3. Calculate the DCV using worksheet B.2-1.
DCV = 1,056 (cubic feet) 1,056 x 0.25 = 264 CF
3a. Is the 36 hour demand greater
than or equal to the DCV?
Yes / X No
3b. Is the 36 hour demand greater than
0.25DCV but less than the full DCV?
Yes / X No
3c. Is the 36 hour demand
less than 0.25DCV?
X Yes
Harvest and use appears to be
feasible. Conduct more detailed
evaluation and sizing calculations
to confirm that DCV can be used
at an adequate rate to meet
drawdown criteria.
Harvest and use may be feasible.
Conduct more detailed evaluation and
sizing calculations to determine
feasibility. Harvest and use may only be
able to be used for a portion of the site,
or (optionally) the storage may need to be
upsized to meet long term capture targets
while draining in longer than 36 hours.
Harvest and use is
considered to be infeasible.
Is harvest and use feasible based on further evaluation?
Yes, refer to Appendix E to select and size harvest and use BMPs.
X No, select alternate BMPs.
I-2 February 2016
Modified Estimated Total Water Use Calculation
Modified ETWU = (ET0wet) x [[∑(PF x HA)/IE] + SLA] x 0.015
Enter Irrigation Efficiency (IE) 0.90
Hydrozone
Plant Water Use
Type (s) (low,
medium, high)
Plant Factor (PF)
Hydrozone Area
(HA) (ft2)
PF x HA (ft2)
1 Low 0.10 3,652 365
2 Moderate 0.30 0 0
3 High 0.80 0 0
365
SLA 1 0 0
Sum 365
Results
gal
cf
cf
Modified ETWU= 16
2
36 hr Demand= 3
Landscaping 36 hour demand 3 cf
Plant Water Use Type Plant Factor
Low 0.1 - 0.2
Moderate 0.3 - 0.7
High 0.80
SLA 1.00
where:
Modified
ETWU
ETowet
PF
HA.
IE
SL\
Estimated daily average water usage during wet season
Average reference evapotranspiration fron,
ovember through April (use 2.7 inches per month,
using CI 1IS Z one 4 from Table G.1-1)
Plant Factor
H ydrozone Area (sq-ft); A section or zone of the
landscaped area having plants with similar water
needs.
~(PF x HA) = TI1e sum of PF x HA for each
individual Hydrozone (accoun ts for different
landscaping zones).
Irrigation Efficiency (assume 90 percent for demand
calculations)
Special L andscape Area (sq-ft); Areas used for active
and passive recreation areas, areas solely dedicated to
the production of fruits and vegetables, and areas
irrigated with reclaimed water.
FORTHCOMING IN FUTURE SUBMITTALS
ATTACHMENT 1D – INFILTRATION FEASIBILITY
ANALYSIS
4010 Morena Boulevard, Suite 108 • San Diego, CA 92117 • (858) 521-1190 • (858) 521-1199 fax • terrapac.net
Mr. Diego Lastres August 9, 2023
Cunningham File No. 22-041
1030 G Street
San Diego, California 92101
Subject: Updated Infiltration Study
Carlsbad by the Sea Summer House
Ocean and Beech Street
Carlsbad, California
Reference: 1) “Geotechnical Investigation for Proposed Memory Care and
Independent Living Facility, Ocean Street, APNs 203-144-0400, 0500,
0600, 0700 and 0800, Carlsbad, California,” prepared by TerraPacific
Consultants, Inc., dated February 25, 2022.
2) “Preliminary Grading Plans for Front Porch Memory Care &
Independent Living, 2710-2740 Ocean Street, Carlsbad, California,”
prepared by BWE, dated February 6, 2023.
Dear Mr. Lastres:
As requested, TerraPacific Consultants, Inc. (TCI) has prepared the following updated
report presenting the findings and recommendations from the recent infiltration study
conducted on-site. This updated report includes the items from the January 2023 City of
Carlsbad Stormwater BMP Design Manual and Worksheet D.1-1. Site infiltration testing
was conducted on February 2, 2023.
The testing was conducted at two locations designated, Test Pits PT-1 and PT-2, in
accordance with the City of Carlsbad Worksheet D.1-1. In addition, six exploratory
borings, B-1 through B-6, were excavated as a part of the referenced geotechnical
investigation. The excavation/test locations are presented on the Geotechnical Plan,
Figure 1 in Appendix A, and the percolation test pit logs and boring logs are presented in
Appendix B.
The testing followed the open-pit method and was conducted at depths of 2.5 feet below
ground surface. Percolation rates were converted to infiltration rates using the Porchet
Method, and a 2x factor of safety was applied and indicated the following results:
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II
Carlsbad by the Sea • Ocean Street, Carlsbad, CA • File No. 22-041 • August 9, 2023
- 3 -
water and resultant saturated soils and perched groundwater conditions impacting
flatwork or pavement sections, utility trench bedding, any subsurface drain systems, or
other improvements cannot be completely ruled out, as such the locations of these items
in relation to the proposed infiltration areas should be properly evaluated during project
design.
The measured site-specific percolation rates for the site indicated rates ranging from 1.7-
inch per hour to 1.9-inch per hour. These rates are consistent with published rates for
sandy type soils, as indicated in USDA, 2008. The percolation rates were converted to
infiltration rates using the Porchet method, and a x2 factor of safety was applied to
determine the estimated reliable infiltration rates of 0.87-inch per hour to 0.95-inch per
hour. The lower of the two rates should be utilized. This low infiltration is also considered
the maximum allowable rate that would not significantly increase the potential for
damage to existing or proposed structures; however, this potential cannot be completely
ruled out. The City of Carlsbad Worksheet D.1-1 is provided in Appendix C.
We greatly appreciate the opportunity to be of service. If you should have any questions
or comments regarding this report or our findings, please do not hesitate to call.
Sincerely,
TerraPacific Consultants, Inc.
Cristopher C. O’Hern, CEG 2397
Senior Engineering Geologist
23Cristopher D1H-er11
APPENDIX A
Figure
•
APPENDIX B
Subsurface Logs
•
Drilling Company:
DESCRIPTION & REMARKSLithologyDe
p
t
h
(f
t
)
Project No:
Project Name:
Location:
Sample Method:
Date:
Logged By:
Instrumentation:
Driller:
22-041
Ocean Street Memory Care
Beech Ave and Ocean Street
Modified California Sampler
2-17-22
O. Brambila
None installed
Native Drilling
F.S.Elevation:
Steve
Drill Rig Type:
Hammer Wt. & Drop:
L.A.R. Solid Flight
140 lbs. for 30"
(%
)
Mo
i
s
t
u
r
e
(p
c
f
)
(6
"
,
1
2
"
,
1
8
"
)
Co
u
n
t
s
Bl
o
w
Ty
p
e
Sa
m
p
l
e
Subsurface Boring Log
B-1Boring No:
US
C
S
Dr
y
D
e
n
s
i
t
y
Total Depth:15.0'Boring
Page 1 of 1
B-1Water:No
Caving:No
Hole Diameter:5"
@2.0', Slightly moist, medium dense
FILL: From 0.0', Silty sand, light orange brown, moist, loose
OLD PARALIC DEPOSITS (QOP6-7): From 4.0', Silty sandstone, light orange brown, slightly moist, dense, slight porosity
From 9.0', Sandstone, orange brown, slightly moist, dense, friable, medium grained, poorly graded
Ring
Ring
Ring
6/7/13
6/14/24
10/12/20
108.6
111.8
--
0
5
10
15
20
25
30
35
40
2.0
5.4
--
0
5
10
15
20
25
30
35
40
Drilling Company:
DESCRIPTION & REMARKSLithologyDe
p
t
h
(f
t
)
Project No:
Project Name:
Location:
Sample Method:
Date:
Logged By:
Instrumentation:
Driller:
22-041
Ocean Street Memory Care
Beech Ave and Ocean Street
Modified California Sampler
2-17-22
O. Brambila
None installed
Native
FSElevation:
Steve
Drill Rig Type:
Hammer Wt. & Drop:
L.A.R. Flight Auger
140 lbs. for 30"
(%
)
Mo
i
s
t
u
r
e
(p
c
f
)
(6
"
,
1
2
"
,
1
8
"
)
Co
u
n
t
s
Bl
o
w
Ty
p
e
Sa
m
p
l
e
Subsurface Boring Log
B-2Boring No:
US
C
S
Dr
y
D
e
n
s
i
t
y
Total Depth:11.5'Boring
Page 1 of 1
B-2Water:No
Caving:No
Hole Diameter:5"
FILL: From 0.0', Silty sand, orange brown, moist to slightly moist, loose
OLD PARALIC DEPOSITS (QOP6-7): From 2.5', Silty sandstone, light red brown, slightly moist, dense, slightly weathered
From 6.0', Sandstone, red brown, slightly moist, dense, fine to medium dense, trace of clay
From 8.0', Silty sandstone, light red brown, slightly moist, dense, friable
Ring
Ring
Ring
5/14/23
17/17/18
11/12/15
--
--
--
0
5
10
15
20
25
30
35
40
--
--
--
0
5
10
15
20
25
30
35
40
Drilling Company:
DESCRIPTION & REMARKSLithologyDe
p
t
h
(f
t
)
Project No:
Project Name:
Location:
Sample Method:
Date:
Logged By:
Instrumentation:
Driller:
22-041
Ocean Street Memory Care
Beech Ave and Ocean Street
Modified California Sampler
2-17-22
O. Brambila
None installed
Native
FSElevation:
Steve
Drill Rig Type:
Hammer Wt. & Drop:
L.A.R. Solid Flight Auger
140 lbs. for 30"
(%
)
Mo
i
s
t
u
r
e
(p
c
f
)
(6
"
,
1
2
"
,
1
8
"
)
Co
u
n
t
s
Bl
o
w
Ty
p
e
Sa
m
p
l
e
Subsurface Boring Log
B-3Boring No:
US
C
S
Dr
y
D
e
n
s
i
t
y
Total Depth:21.5'Boring
Page 1 of 1
B-3Water:No
Caving:No
Hole Diameter:5"
FILL: From 0.0', Silty sand, orange brown to red brown, moist to slightly moist, loose
OLD PARALIC DEPOSITS (QOP6-7): From 2.5', Silty sandstone, red brown, slightly moist, medium dense to dense, slightly weathered, slight porosity
From 9.0', Sandstone, light orange brown, slightly moist, dense, fine to medium grained, friable
From 16.0', Sandstone, light tan brown, slightly moist, dense, friable, medium grained
Bulk
Ring
Ring
Ring
--
22/26/29
12/14/17
9/10/13
--
--
--
--
0
5
10
15
20
25
30
35
40
--
--
--
--
0
5
10
15
20
25
30
35
40
Drilling Company:
DESCRIPTION & REMARKSLithologyDe
p
t
h
(f
t
)
Project No:
Project Name:
Location:
Sample Method:
Date:
Logged By:
Instrumentation:
Driller:
22-041
Ocean Street Memory Care
Beech Ave and Ocean Street
Modified California Sampler
2-17-22
O. Brambila
None installed
Native
FSElevation:
Steve
Drill Rig Type:
Hammer Wt. & Drop:
L.A.R. Solid Flight Auger
140 lbs. for 30"
(%
)
Mo
i
s
t
u
r
e
(p
c
f
)
(6
"
,
1
2
"
,
1
8
"
)
Co
u
n
t
s
Bl
o
w
Ty
p
e
Sa
m
p
l
e
Subsurface Boring Log
B-4Boring No:
US
C
S
Dr
y
D
e
n
s
i
t
y
Total Depth:11.5'Boring
Page 1 of 1
B-4Water:No
Caving:No
Hole Diameter:5"
FILL: From 0.0', Silty sand, light orange brown to red brown, moist, loose
OLD PARALIC DEPOSITS (QOP6-7): From 3.0', Silty sandstone, orange brown, slightly moist, medium dense, slightly weathered, friable
From 9.0', Silty sandstone, red brown, slightly moist, dense, friable
Ring
Ring
14/15/17
18/22/30
--
--
0
5
10
15
20
25
30
35
40
--
--
0
5
10
15
20
25
30
35
40
Drilling Company:
DESCRIPTION & REMARKSLithologyDe
p
t
h
(f
t
)
Project No:
Project Name:
Location:
Sample Method:
Date:
Logged By:
Instrumentation:
Driller:
22-041
Ocean Street Memory Care
Beech Ave and Ocean Street
Modified California Sampler
2-17-22
O. Brambila
None installed
Native
FSElevation:
Steve
Drill Rig Type:
Hammer Wt. & Drop:
L.A.R. Solid Flight Auger
140 lbs. for 30"
(%
)
Mo
i
s
t
u
r
e
(p
c
f
)
(6
"
,
1
2
"
,
1
8
"
)
Co
u
n
t
s
Bl
o
w
Ty
p
e
Sa
m
p
l
e
Subsurface Boring Log
B-5Boring No:
US
C
S
Dr
y
D
e
n
s
i
t
y
Total Depth:9.0 Boring
Page 1 of 1
B-5Water:No
Caving:No
Hole Diameter:5"
FILL: From 0.0', Silty sand, light orange brown, moist, loose
OLD PARALIC DEPOSITS (QOP6-7): From 2.5', Silty sandstone, orange brown, slightly moist, dense, slightly weathered Ring
SPT
6/9/13
8/8/10
--
--
0
5
10
15
20
25
30
35
40
--
--
0
5
10
15
20
25
30
35
40
Drilling Company:
DESCRIPTION & REMARKSLithologyDe
p
t
h
(f
t
)
Project No:
Project Name:
Location:
Sample Method:
Date:
Logged By:
Instrumentation:
Driller:
22-041
Ocean Street Memory Care
Beech Ave and Ocean Street
Modified California Sampler
2-17-22
O. Brambila
None installed
Native
FSElevation:
Steve
Drill Rig Type:
Hammer Wt. & Drop:
L.A.R. Solid Flight Auger
140 lbs. for 30"
(%
)
Mo
i
s
t
u
r
e
(p
c
f
)
(6
"
,
1
2
"
,
1
8
"
)
Co
u
n
t
s
Bl
o
w
Ty
p
e
Sa
m
p
l
e
Subsurface Boring Log
B-6Boring No:
US
C
S
Dr
y
D
e
n
s
i
t
y
Total Depth:36.5'Boring
Page 1 of 1
B-6Water:No
Caving:No
Hole Diameter:5"
@30.0', Some boulders
@32.0', Groundwater
FILL: From 0.0', Silty sand, light orange brown, moist, loose
OLD PARALIC DEPOSIT (QOP6-7): From 2.0', Silty sandstone, red brown, slightly moist, medium dense, slightly weathered
From 8.0', Sandstone, orange brown, slightly moist, dense, friable
From 12.0', Silty sandstone, orange brown, slightly moist, dense, fine to medium grained, trace of clay
From 16.0', Sandstone, pale brown, slightly moist, dense, poorly graded, friable
From 26.0', Sandstone, pale brown, moist, dense, gravel and cobbles
From 33.0', Sandstone, light gray to pale brown, wet, dense
Ring
Ring
9/13/17
7/18/34
--
--
0
5
10
15
20
25
30
35
40
--
--
0
5
10
15
20
25
30
35
40
~ :r. :r. :r. ~
;r. ~ ;r. :!: ~ -
:T. :r. :r:. -:T. :r. :r:. -:T. :r. :r:.
:T. :r. :r:. -:T. :r. :r:. -:T. ':r.' :r: • --. .. -. .
---
I, .:T. •I,• -:T. :r. :r:
:T. ;-r: :r: : -
:T. :r. :r: --. .. -. .
---------------------
DESCRIPTION & REMARKSLithology
De
p
t
h
Project No:
Project Name:
Location:
Sample Method:
Date:
Logged By:
Instrumentation:
22-041
Ocean Street Memory Care
Beech and Ocean Street
N/A
2-2-23
C. O'Hern
None installed
Elevation:Pad Hammer Wt. & Drop:
Excavation Method:
Excavator:
Excavating Company:
N/A
Hand labor
Andy
W.A. Kifer
(%
)
Mo
i
s
t
u
r
e
(p
c
f
)
Co
u
n
t
s
Bl
o
w
Ty
p
e
Sa
m
p
l
e
Percolation Test No: PT-1
(f
t
)
US
C
S
Dr
y
D
e
n
s
i
t
y
Percolation Testing Log
Total Depth:
Page 1 of 1
2.5'
Water:No
Caving:No PT-1
Perc. Test
Hole Diamater:24"
0
1
2
3
4
5
6
7
8
9
10
0
1
2
3
4
5
6
7
8
9
10
FILL: From 0.0', Silty sand, orange brown, slightly moist, loose to medium dense
NATIVE (Old Paralic Deposits, Unit 6): From 2.1', Silty sandstone, pale orange brown, slightly moist, medium dense
Simple Open Pit Test 24" diameter x 2.5' deep, 6" Water addedTime (t) / Total Depth (dt) / Water Depth (Do, Df) / Drop (Delta H)
12:00 pm Fill to 6"12:54 pm 6.0" drop, refill to 6"1:54 pm 4.3" drop, refill to 6"2:54 pm 3.1" drop, refill to 6" -- Final Reading
Infiltration Rate (Porchet Method)-It = DeltaH*60*r/DeltaH(r+2Havg)r=(A/pi)0.5^ 24 x 24/3.14 = 13.5"It = (3.1")(60 min/hr) (13.5")/(60 min)(23.9")It=1.74"/hr
....... ... ... ... . ;r, ;r, ;r, . ... ... ... . ;r, ;r, ;r, . ... ... ... . ;r, ;r, ;r, . ... ... ... . ;r, ;r, ;r, . ... ... ... .
;r, ;r, ;r, . ... ... ... .
;r, ;r, ;r, . ... ... ... .
;r, ;r, ;r, . ... ... ... . ;r, ;r, ;r, . ... ... ... .
DESCRIPTION & REMARKSLithology
De
p
t
h
Project No:
Project Name:
Location:
Sample Method:
Date:
Logged By:
Instrumentation:
22-041
Ocean Street Memory Care
Beech and Ocean Street
N/A
2-2-23
C. O'Hern
None installed
Elevation:Pad Hammer Wt. & Drop:
Excavation Method:
Excavator:
Excavating Company:
N/A
Hand labor
Andy
W.A. Kifer
(%
)
Mo
i
s
t
u
r
e
(p
c
f
)
Co
u
n
t
s
Bl
o
w
Ty
p
e
Sa
m
p
l
e
Percolation Test No: PT-2
(f
t
)
US
C
S
Dr
y
D
e
n
s
i
t
y
Percolation Testing Log
Total Depth:
Page 1 of 1
2.5'
Water:No
Caving:No PT-2
Perc. Test
Hole Diamater:24"
0
1
2
3
4
5
6
7
8
9
10
0
1
2
3
4
5
6
7
8
9
10
FILL: From 0.0', Silty sand, medium orange brown, slightly moist, loose to medium dense
NATIVE (Old Paralic Deposits, Unit 6): From 2.2', silty sandstone, pale orange brown, slightly moist, medium dense
Simple Open Pit Test 24" diameter x 2.5' deep, 6" Water addedTime (t) / Total Depth (dt) / Water Depth (Do, Df) / Drop (Delta H)
12:05 pm Fill to 6"1:00 pm6.0" drop, refill to 6"2:00 pm4.8" drop, refill to 6"3:00 pm3.4" drop -- Final Reading
Infiltration Rate (Porchet Method)-It = DeltaH*60*r/DeltaH(r+2Havg)r=(A/pi)0.5^ (25 x 22)/3.14 = 13.2"It = (3.4")(60 min/hr) (13.2")/(60 min)(23.7")It=1.91"/hr
......... ............ ;r, : ;r, : ;r, . ............ ;r, : ;r, : ;r, . ............
;r, : ;r, : ;r, . ............
;r, : ;r, : ;r, . ............
;r, : ;r, : ;r, . ............
;r, : ;r, : ;r, . ............
;r, : ;r, : ;r, . ............ ;r, : ;r, : ;r, . ............ ;r, : ;r, : ;r, . ............ . . . . . .......
APPENDIX C
City of Carlsbad – BMP Design Manual
Worksheet D.1-1, January 2023
•
Appendix D: Geotechnical Engineer Analysis
D-1 Jan. 2023
Appendix D Geotechnical Engineer
Analysis
Analysis of Infiltration Restrictions
This section is only applicable if the analysis of infiltration restrictions is performed by a
licensed engineer practicing in geotechnical engineering. The SWQMP Preparer and
Geotechnical Engineer must work collaboratively to identify any infiltration restrictions identified in
Table D.1-1 below. Upon completion of this section, the Geotechnical Engineer must characterize
each DMA as Restricted or Unrestricted for infiltration and provide adequate support/discussion in
the geotechnical report. A DMA is considered restricted when one or more restrictions exist which
cannot be reasonably resolved through site design changes.
Table D.1-1: Considerations for Geotechnical Analysis of Infiltration Restrictions
Restriction Element
Is Element
Applicable?
(Yes/No)
Mandatory
Considerations
BMP is within 100’ of Contaminated Soils
BMP is within 100’ of Industrial Activities Lacking Source Control
BMP is within 100’ of Well/Groundwater Basin
BMP is within 50’ of Septic Tanks/Leach Fields
BMP is within 10’ of Structures/Tanks/Walls
BMP is within 10’ of Sewer Utilities
BMP is within 10’ of Groundwater Table
BMP is within Hydric Soils
BMP is within Highly Liquefiable Soils and has Connectivity to Structures
BMP is within 1.5 Times the Height of Adjacent Steep Slopes (≥25%)
County Staff has Assigned “Restricted” Infiltration Category
Optional
Considerations
BMP is within Predominantly Type D Soil
BMP is within 10’ of Property Line
BMP is within Fill Depths of ≥5’ (Existing or Proposed)
BMP is within 10’ of Underground Utilities
BMP is within 250’ of Ephemeral Stream
Other (Provide detailed geotechnical support)
Result
Based on examination of the best available information,
I have not identified any restrictions above.
Unrestricted
Based on examination of the best available information,
I have identified one or more restrictions above.
Restricted
Table D.1-1 is divided into Mandatory Considerations and Optional Considerations. Mandatory
no
no
no
no
no
no
no
no
no
no
no
no
no
no
no
no
22-041 Ocean Street Memory Care
D.1
Appendix D: Geotechnical Engineer Analysis
D-2 Jan. 2023
Considerations include elements that may pose a significant risk to human health and safety and must
always be evaluated. Optional Considerations include elements that are not necessarily associated with
human health and safety, so analysis is not mandated through this guidance document. All elements
presented in this table are subject to the discretion of the Geotechnical Engineer if adequate
supporting information is provided.
Applicants must evaluate infiltration restrictions through use of the best available data. A list of
resources available for evaluation is provided in Section B.2
Determination of Design Infiltration Rates
This section is only applicable if the determination of design infiltration rates is performed
by a licensed engineer practicing in geotechnical engineering. The guidance in this section
identifies methods for identifying observed infiltration rates, corrected infiltration rates, safety factors,
and design infiltration rates for use in structural BMP design. Upon completion of this section, the
Geotechnical Engineer must recommend a design infiltration rate for each DMA and provide
adequate support/discussion in the geotechnical report.
Table D.2-1: Elements for Determination of Design Infiltration Rates
Item Value Unit
Initial Infiltration Rate
Identify per Section D.2.1 in/hr
Corrected Infiltration Rate
Identify per Section D.2.2 in/hr
Safety Factor
Identify per Section D.2.3 unitless
Design Infiltration Rate
Corrected Infiltration Rate ÷ Safety Factor in/hr
2.00
3.18
1.74
0.87
D.2
Appendix D: Geotechnical Engineer Analysis
D-3 Jan. 2023
Initial Infiltration Rate
For purposes of this manual, the initial infiltration rate is the infiltration rate that has been identified
based on the initial testing methods. Some of the acceptable methods for determining initial infiltration
rates are presented in Table D.2-2 below, though other testing methods may be acceptable as evaluated
by the geotechnical engineer. This table identifies what methods require application of correction
factors, safety factors, and what BMPs types are ultimately acceptable for each testing method. The
geotechnical engineer should use professional discretion when selecting a testing method as it may
ultimately impact the types of BMPs that are permitted.
Table D.2-2: Acceptable Initial Infiltration Rate Methods
Category Test Correction Factor Safety
Factor
Suitable for
Following
BMPs
Desktop
Methods*
NRCS Soil Survey
Maps
Not
Applicable
Not
Applicable
BMPs with
Underdrains
Correlation
Methods
Grain Size Analysis
Not
Applicable
Required
(See Section D.2.3)
BMPs with
Underdrains
Cone Penetrometer
Testing
Laboratory
Permeability Tests
Percolation
Tests
Simple Open Pit Test
Required
(See Section D.2.2)
Required
(See Section D.2.3) Any BMP Type
Open Pit Falling Head
Test
Well Permeameter
Method
Borehole Percolation
Tests
Infiltration
Tests
Double Ring
Infiltrometer Test
Not
Applicable
Required
(See Section D.2.3) Any BMP Type
Single Ring
Infiltrometer Test
Large-scale Pilot
Infiltration Test
Smaller-scale Pilot
Infiltration Test
D.2.1
Appendix D: Geotechnical Engineer Analysis
D-4 Jan. 2023
*Desktop methods may be performed without a geotechnical engineer. Refer to Basic Infiltration
Analysis guidance in Section B.2.3 for more information.
NRCS Soil Survey Maps: NRCS Soil Survey maps can be used to establish approximate infiltration
rates for use in BMP design. Under this method, default design infiltration rates may be applied based
on the predominant NRCS soil type present within a proposed BMP location. Default design
infiltration rates (in/hr) for each NRCS soil type are: A=0.300, B=0.200, C=0.100, D=0.025,
Restricted=0.000. Use of these default design infiltration rates does not require application of any
correction factors or safety factors.
Grain Size Analysis Testing: Hydraulic conductivity can be estimated indirectly from correlations
with soil grain-size distributions. While this method is approximate, correlations have been relatively
well established for some soil conditions. One of the most commonly used correlations between grain
size parameters and hydraulic conductivity is the Hazen (1892, 1911) empirical formula (Philips and
Kitch, 2011), but a variety of others have been developed. Correlations must be developed based on
testing of site-specific soils. For purposes of this manual, saturated hydraulic conductivity and
infiltration rate can be assumed to be equal.
Cone Penetrometer Testing: Hydraulic conductivity can be estimated indirectly from cone
penetrometer testing (CPT). A cone penetrometer test involves advancing a small probe into the soil
and measuring the relative resistance encountered by the probe as it is advanced. The signal returned
from this test can be interpreted to yield estimated soil types and the location of key transitions
between soil layers. If this method is used, correlations must be developed based on testing of site-
specific soils. For purposes of this manual, saturated hydraulic conductivity and infiltration rate can
be assumed to be equal.
Laboratory Permeability Testing: Laboratory testing can be performed to help evaluate the
infiltration rates. The laboratory tests should be in accordance with ASTM or other approved
procedures (e.g. ASTM D 5084 or D 5856). Several tests may be required from samples at different
elevations to help evaluate the permeability characteristics of the soil strata.
Simple Open Pit Test: The Simple Open Pit Test is a falling head test in which a hole at least two
feet in diameter is filled with water to a level of 6” above the bottom. Water level is checked and
recorded regularly until either an hour has passed or the entire volume has infiltrated. The test is
repeated two more times in succession and the rate at which the water level falls in the third test is
used as the infiltration rate. This test identifies a percolation rate that should be converted to an
infiltration rate using the Porchet method.
Open Pit Falling Head Test: This test is similar to the Simple Open Pit Test, but covers a larger
footprint, includes more specific instructions, returns more precise measurements, and generally
should be overseen by a geotechnical professional. Nonetheless, it remains a relatively simple test.
Appendix D: Geotechnical Engineer Analysis
D-5 Jan. 2023
To perform this test, a hole is excavated at least 2 feet wide by 4 feet long (larger is preferred) and to
a depth of at least 12 inches. The bottom of the hole should be approximately at the depth of the
proposed infiltrating surface of the BMP. The hole is pre-soaked by filling it with water at least a foot
above the soil to be tested and leaving it at least 4 hours (or overnight if clays are present). After pre-
soaking, the hole is refilled to a depth of 12 inches and allow it to drain for one hour (2 hours for
slower soils), measuring the rate at which the water level drops. The test is then repeated until
successive trials yield a result with less than 10 percent change.
Well Permeameter Method (USBR 7300-89): Well permeameter methods were originally
developed for purposes of assessing aquifer permeability and associated yield of drinking water wells.
This family of tests is most applicable in situations in which infiltration facilities will be placed
substantially below existing grade, which limits the use of surface testing methods.
In general, this test involves drilling a 6 inch to 8 inch test well to the depth of interest and maintaining
a constant head until a constant flow rate has been achieved. Water level is maintained with down-
hole floats. A smaller diameter boring may be adequate, however this then requires a different
correction factor to account for the increased variability expected. The Porchet method or the
nomographs provided in the USBR Drainage Manual (United States Department of the Interior,
Bureau of Reclamation, 1993) are used to convert the measured rate of percolation to an estimate of
vertical hydraulic conductivity.
While these tests have applicability in screening level analysis, considerable uncertainty is introduced
in the step of converting direct percolation measurements to estimates of vertical infiltration.
Additionally, this testing method is prone to yielding erroneous results cases where the vertical horizon
of the test intersects with minor lenses of sandy soils that allow water to dissipate laterally at a much
greater rate than would be expected in a full-scale facility. To improve the interpretation of this test
method, a continuous bore log should be inspected to determine whether thin lenses of material may
be biasing results at the strata where testing is conducted. Consult USBR procedure 7300-89 for more
details.
Source: (United States Department of the Interior, Bureau of Reclamation, 1990, 1993)
Borehole Percolation Tests: Borehole percolation tests were originally developed as empirical tests
to estimate the capacity of onsite sewage disposal systems (septic system leach fields), but have more
recently been adopted into use for evaluating storm water infiltration. Similar to the well permeameter
method, borehole percolation methods primarily measure lateral infiltration into the walls of the
boring and are designed for situations in which infiltration facilities will be placed well below current
grade. The percolation rate obtained in this test should be converted to an infiltration rate using a
technique such as the Porchet method.
This test is generally implemented similarly to the USBR Well Permeameter Method. Per the Riverside
Appendix D: Geotechnical Engineer Analysis
D-6 Jan. 2023
County Borehole Percolation method, a hole is bored to a depth at least 5 times the borehole radius.
The hole is presoaked for 24 hours (or at least 2 hours if sandy soils with no clay). The hole is filled
to approximately the anticipated top of the proposed infiltration basin. Rates of fall are measured for
six hours, refilling each half hour (or 10 minutes for sand). Tests are generally repeated until consistent
results are obtained.
The same limitations described for the well permeameter method apply to borehole percolation tests,
and their applicability is generally limited to initial screening. To improve the interpretation of this test
method, a continuous soil core can be extracted from the hole and below the test depth, following
testing, to determine whether thin lenses of material may be biasing results at the strata where testing
is conducted.
Sources: Riverside County Percolation Test (2011), California Test 750 (Caltrans, 1986), San
Bernardino County Percolation Test (1992); USEPA Falling Head Test (USEPA, 1980).
In comparison to a double-ring infiltrometer, this test has the advantage of measuring infiltration over
a larger area and better resembles the dimensionality of a typical small scale BMP. This test identifies
a percolation rate that should be converted to an infiltration rate using the Porchet method. However,
if this method is used to identify rates for a drywell BMP, the correction factor can be omitted at the
discretion of the geotechnical engineer.
Double Ring Infiltrometer Test (ASTM 3385): The Double Ring Infiltrometer was originally
developed to estimate the saturated hydraulic conductivity of low permeability materials, such as clay
liners for ponds, but has seen significant use in storm water applications. The most recent revision of
this method from 2009 is known as ASTM 3385-09. The testing apparatus is designed with concentric
rings that form an inner ring and an annulus between the inner and outer rings. Infiltration from the
annulus between the two rings is intended to saturate the soil outside of the inner ring such that
infiltration from the inner ring is restricted primarily to the vertical direction.
To conduct this test, both the center ring and annulus between the rings are filled with water. There
is no pre-wetting of the soil in this test. However, a constant head of 1 to 6 inches is maintained for 6
hours, or until a constant flow rate is established. Both the inner flow rate and annular flow rate are
recorded, but if they are different, the inner flow rate should be used. There are a variety of approaches
that are used to maintain a constant head on the system, including use of a Mariotte tube, constant
level float valves, or manual observation and filling. This test must be conducted at the elevation of
the proposed infiltrating surface; therefore application of this test is limited in cases where the
infiltration surface is a significant distance below existing grade at the time of testing.
This test is generally considered to provide a direct estimate of vertical infiltration rate for the specific
point tested and is highly replicable. However, given the small diameter of the inner ring (standard
diameter is 12 inches, but it can be larger), this test only measures infiltration rate in a small area.
Appendix D: Geotechnical Engineer Analysis
D-7 Jan. 2023
Additionally, given the small quantity of water used in this test compared to larger scale tests, this test
may be biased high in cases where the long term infiltration rate is governed by groundwater mounding
and the rate at which mounding dissipates (i.e., the capacity of the infiltration receptor). Finally, the
added effort and cost of isolating vertical infiltration rate may not necessarily be warranted considering
that BMPs typically have a lateral component of infiltration as well. Therefore, while this method has
the advantages of being technical rigorous and well standardized, it should not necessarily be assumed
to be the most representative test for estimating full-scale infiltration rates. Source: American Society
for Testing and Materials (ASTM) International (2009).
Single Ring Infiltrometer Test: The single ring infiltrometer test is not a standardized ASTM test,
however it is a relatively well-controlled test and shares many similarities with the ASTM standard
double ring infiltrometer test (ASTM 3385-09). This test is a constant head test using a large ring
(preferably greater than 40 inches in diameter) usually driven 12 inches into the soil. Water is ponded
above the surface. The rate of water addition is recorded and infiltration rate is determined after the
flow rate has stabilized. Water can be added either manually or automatically.
The single ring used in this test tends to be larger than the inner ring used in the double ring test.
Driving the ring into the ground limits lateral infiltration; however some lateral infiltration is generally
considered to occur. Experience in Riverside County (CA) has shown that this test gives results that
are close to full-scale infiltration facilities. The primary advantages of this test are that it is relatively
simple to conduct and has a larger footprint (compared to the double-ring method) and restricts
horizontal infiltration and is more standardized (compared to open pit methods). However, it is still a
relatively small scale test and can only be reasonably conducted near the existing ground surface.
Large Scale Pilot Infiltration Test: As its name implies, this test is closer in scale to a full-scale
infiltration facility. This test was developed by Washington State Department of Ecology specifically
for storm water applications.
To perform this test, a test pit is excavated with a horizontal surface area of roughly 100 square feet
to a depth that allows 3 to 4 feet of ponding above the expected bottom of the infiltration facility.
Water is continually pumped into the system to maintain a constant water level (between 3 and 4 feet
about the bottom of the pit, but not more than the estimated water depth in the proposed facility) and
the flow rate is recorded. The test is continued until the flow rate stabilizes. Infiltration rate is
calculated by dividing the flow rate by the surface area of the pit.
This test has the advantage of being more resistant to bias from localized soil variability and being
more similar to the dimensionality and scale of full scale BMPs. It is also more likely to detect long
term decline in infiltration rates associated with groundwater mounding. As such, it remains the
preferred test for establishing design infiltration rates in Western Washington (Washington State
Department of Ecology, 2012). In a comparative evaluation of test methods, this method was found
to provide a more reliable estimate of full-scale infiltration rate than double ring infiltrometer and
Appendix D: Geotechnical Engineer Analysis
D-8 Jan. 2023
borehole percolation tests (Philips and Kitch 2011).
The difficulty encountered in this method is that it requires a larger area be excavated than the other
methods, and this in turn requires larger equipment for excavation and a greater supply of water.
However, this method should be strongly considered when less information is known about spatial
variability of soils and/or a higher degree of certainty in estimated infiltration rates is desired.
Smaller-Scale Pilot Infiltration Test: The smaller-scale PIT is conducted similarly to the large-scale
PIT but involves a smaller excavation, ranging from 20 to 32 square feet instead of 100 square feet
for the large-scale PIT, with similar depths. The primary advantage of this test compared to the full-
scale PIT is that it requires less excavation volume and less water. It may be more suitable for small-
scale distributed infiltration controls where the need to conduct a greater number of tests outweighs
the accuracy that must be obtained in each test, and where groundwater mounding is not as likely to
be an issue.
Corrected Infiltration Rate
For purposes of this manual, the corrected infiltration rate is the initial infiltration rate as modified by
appropriate correction factors needed to convert from percolation to infiltration or to correct for
effects of water temperature. The sections below present discussion on correction factors that should
be considered by the Geotechnical Engineer.
D.2.2.1 Percolation Rate Correction Factor
A common misunderstanding is that the “percolation rate” obtained from a percolation test is
equivalent to the “infiltration rate” obtained from tests such as a single or double ring infiltrometer
test which is equivalent to the “saturated hydraulic conductivity”. In fact, these terms have different
meanings. Saturated hydraulic conductivity is an intrinsic property of a specific soil sample under a
given density. It is a coefficient in Darcy’s equation (Darcy 1856) that characterizes the flux of water
that will occur under a given gradient. The measurement of saturated hydraulic conductivity in a
laboratory test is typically referred to as “permeability”, which is a function of the density, structure,
stratification, fines, and discontinuities of a given sample under given controlled conditions. In
contrast, infiltration is the downward entry of water into the soil. The velocity at which water enters
the soil is infiltration rate. Infiltration rate is typically expressed in inches per hour. For the purposes
of this manual, saturated hydraulic conductivity and infiltration rate can be assumed to be equal.
Similarly, to permeability, infiltration rate can be limited by a number of factors including the layering
of soil, density, discontinuities, and initial moisture content. These factors control how quickly water
can move through a soil. However, infiltration rate can also be influenced by mounding of
groundwater, and the rate at which water dissipates horizontally below a BMP – both of which
describe the “capacity” of the “infiltration receptor” to accept this water over an extended period. For
this reason, an infiltration test should ideally be conducted for a relatively long duration resembling a
series of storm events so that the capacity of the infiltration receptor is evaluated as well as the rate at
D.2.2
Appendix D: Geotechnical Engineer Analysis
D-9 Jan. 2023
which water can enter the system. Infiltration rates are generally tested with larger diameter holes, pits,
or apparatuses intended to enforce a primarily vertical direction of flux.
In contrast, percolation is tested with small diameter holes, and it is mostly a lateral phenomenon. The
direct measurement yielded by a percolation test tends to overestimate the infiltration rate, except
perhaps in cases in which a BMP has similar dimensionality to the borehole, such as a dry well.
Adjustment of percolation rates may be made to an infiltration rate using a technique such as the
Porchet Method. For drywell BMPs this adjustment may be determined per other methods, (i.e. USBR
7300-89), or may be omitted entirely at the discretion of the geotechnical engineer.
Percolation Rate Conversion Example
Problem:
Apply the Porchet Method (Inverse Borehole Method) to determine the corrected infiltration rate from the
following inputs:
• Total depth of test hole, DT = 60 inches
• Initial depth to water, DO = 12.25 inches
• Final depth to water, Df = 13.75 inches
• Test hole radius, r = 4 inches
• Time interval, Δt = 10 minutes
Appendix D: Geotechnical Engineer Analysis
D-10 Jan. 2023
Solution:
1. Solve for the height of water at the beginning of the selected time interval, HO:
HO = DT - DO = 60 - 12.25 = 47.75 inches
2. Solve for the height of water at the end of the selected time interval, Hf:
Hf = DT - Df = 60 -13.75 = 46.25 inches
3. Solve for the change in height of water over the selected time interval, ΔH:
ΔH = HO - Hf = 47.75 - 46.25 = 1.50 inches
4. Calculate the average head over the selected time interval, Havg:
Havg = (Ho + Hf)/2 = (47.75 + 46.25)/2 = 47.00 inches
5. Calculate the tested infiltration rate, It, using the following equation:
It= (ΔH*60*r) /(Δt*(r+2Havg))
It = (1.50 in * 60 min/hr * 4 in) / (10 min * (4 inch + (2 * 47 in))) = 0.37 in/hr
D.2.2.2 Temperature Correction Factor
The rate of infiltration through soil is affected by the viscosity of water, which in turn is affected by
the temperature of water. As such, infiltration rate is strongly dependent on the temperature of the
infiltrating water (Cedergren, 1997). For example, Emerson (2008) found that wintertime infiltration
rates below a BMP in Pennsylvania were approximately half their peak summertime rates. As such, it
is important to consider the effects of temperature when planning tests and interpreting results.
If possible, testing should be conducted at a temperature that approximates the typical runoff
temperatures for the site during the times when rainfall occurs. If this is not possible, then the results
of infiltration tests should be adjusted to account for the difference between the temperature at the
time of testing and the typical temperature of runoff when rainfall occurs. The measured infiltration
can be adjusted by the ratio of the viscosity at the test temperature versus the typical temperature
when rainfall occurs (Cedergren, 1997), per the following formula:
Appendix D: Geotechnical Engineer Analysis
D-11 Jan. 2023
×=
Typical
TestTestTypicalKKµ
µ
Where:
KTypical = the typical infiltration rate expected at typical temperatures when rainfall occurs
KTest = the infiltration rate measured or estimated under the conditions of the test
µTypical = the viscosity of water at the typical temperature expected when rainfall occurs
µTest = the viscosity of water at the temperature at which the test was conducted
Safety Factors
A safety factor between 2.0 and 9.0 must be applied to the infiltration rates determined above1.
Application of a safety factor reduces initial or corrected infiltration rates in order to account for
various considerations that can impact infiltration rates measured rates over time. In order to minimize
safety factor impacts, applicants should consider performing rigorous site investigation, incorporating
pretreatment and resiliency into the site design, and taking steps to reduce incidental compaction
within BMP footprints.
If the proposed BMP utilizes an underdrain, a default safety factor of 2.0 may be applied or a more
detailed safety factor may be determined per Table D.2-3. If the proposed BMP does not utilize an
underdrain, then the safety factor must be determined through completion of Table D.2-3.
1 Use of default design infiltration rates based on NRCS soil type does not require application of safety factor.
D.2.3
Appendix D: Geotechnical Engineer Analysis
D-12 Jan. 2023
Table D.2-3: Determination of Safety Factor
Consideration Assigned
Weight (w)
Factor
Value (v)
Product (p)
p = w x v
Suitability
Assessment
(A)
Infiltration Testing Method 0.25
Refer to
Table D.2-4
Soil Texture Class 0.25
Soil Variability 0.25
Depth to Groundwater/Obstruction 0.25
Suitability Assessment Safety Factor, SA = Σp
Design
(B)
Pretreatment 0.50
Refer to
Table D.2-4
Resiliency 0.25
Compaction 0.25
Design Safety Factor, SB = Σp
Safety Factor, S = SA x SB
(Must be always greater than or equal to 2)
The geotechnical engineer should reference Table D.2-4 below in order to determine appropriate
factor values for use in the table above. The values in the table below are subjective in nature and
the geotechnical engineer may use professional discretion in how the points are assigned.
0.50
0.50
0.50
0.50
0.50
0.50
0.50
1.00
2.00
2.00
Appendix D: Geotechnical Engineer Analysis
D-13 Jan. 2023
Table D.2-4: Guidance for Determining Individual Factor Values
Consideration High Concern
(3 points)
Medium Concern
(2 points)
Low Concern
(1 point)
Infiltration
Testing
Method
Any At least 2 tests of any kind
within 50’ of BMP.
At least 4 tests within BMP
footprint, OR Large/Small
Scale Pilot Infiltration Testing
over at least 5% of BMP
footprint.
Soil Texture
Class
Unknown, Silty,
or Clayey Loamy Granular/Slightly Loamy
Soil
Variability
Unknown or
High Moderately Homogeneous Significantly Homogeneous
Depth to
Groundwater/
Obstruction
<5’ below BMP 5-15’ below BMP >15’ below BMP
Pretreatment None/Minimal
Provides good pretreatment
OR does not receive significant
runoff from unpaved areas
Provides excellent pretreatment
OR only receives runoff from
rooftops and road surfaces.
Resiliency None/Minimal
Includes underdrain/backup
drainage that ensures ponding
draws down in <96 hours
Includes underdrain/backup
drainage AND supports easy
restoration of impacted
infiltration rates.
Compaction Moderate
Likelihood Low Likelihood Very Low Likelihood
Appendix D: Geotechnical Engineer Analysis
D-14 Jan. 2023
Geotechnical Reporting Requirements
This section is only applicable if a licensed engineer practicing in geotechnical engineering
has performed the determination of infiltration restrictions and/or design infiltration rates.
The geotechnical report must document the following items in the geotechnical report.
• Date of site analysis
• Scope and results of testing
• Public health and safety requirements that affect infiltration locations
o Must address Mandatory Considerations presented in Appendix D.1
• Conclusions
o Characterize DMAs as Restricted or Unrestricted for Infiltration
o Identify Design Infiltration Rates for DMAs
• Correspondence between City Staff and Geotechnical Engineer (if applicable)
o Development status of site prior to the project application (i.e. new development with
raw ungraded land, or redevelopment with existing graded conditions)
o The history of design discussions for the site proposed project
o Site design alternatives considered to achieve infiltration or partial infiltration on site
o Physical impairments and public safety concerns (i.e. fire road egress, sewer lines, etc)
o The extent low impact development BMP requirements were included in the project
design
It is ultimately the responsibility of the SWQMP Preparer (not the geotechnical engineer) to
interpret the conclusions made in the geotechnical report and ensure they are appropriately
supported/reflected in associated SWQMP submittal materials such as checklists, narratives,
calculations, exhibits, and supplemental reports.
D.3
ATTACHMENT 1E – POLLUTANT CONTROL SIZING
Project: Front Porch
DMA A-5 (BMP #1)
Area Weighted Runoff Factor (C )
Surface Type Area - A (sf) C - Factor C X A Weighted C-
Factor
Impervious 3,920 0.90 3,528
LaThdscape 275 0.10 28
Gravel/DG 0 0.30 0
Total 4,195 3,556 0.848
0.10 Acres
MWS Flow Based BMP Sizing
ITREAT = 0.2 in/hr (Intensity of rainfall)
QTREAT = C x ITREAT x A cfs (Treatment flow rate)
Design Flow (cfs) = 1.5* QTreat (Per Section F.2.2 of Storm Water Standards)
BMP # DMA Runoff
Coefficient
(C )
QTREAT =
Design Flow
(cfs)
BMP Sizing
ID # Area (ac) MWS Model Selected BMP's
Flow Rate (cfs)
1 #5 0.10 0.85 0.02 0.024 MWS-L-4-4 0.052
Note: All selected modular wetlands treatment flow rates exceed the DMAs' design flow
I
WETLANDMEDIA TREATMENT FLOW
MODEL# DIMENSIONS SURFACE AREA RATE
(sq. ft.) (cfs)
MWS-L-4 -4 4' x4' 23 0.052
MWS-L-4 -6 4' X 6' 32 0.073
MWS-L-4-8 4' x8' 50 0 .11 5
MWS-L-4 -13 4' x13' 63 0.144
MWS-L-4 -15 4' X 15' 76 0 .175
MWS-L-4 -17 4' x 17' 90 0.206
MWS-L-4-19 4' X 19' 103 0.237
MWS-L-4-21 4' X 21' 117 0.268
MWS-L-6 -8 7' X 9' 64 0 .147
MWS-L-8-8 8' x8' 100 0.230
MWS-L-8 -1 2 8' X 12' 151 0.34 6
MWS-L-8 -1 6 8' x 16' 201 0.462
MWS-L-8 -20 9' X 21' 252 0.577
MWS•L-8 -24 9' X 25' 302 0.693
MWS-L-10-20 10' X 20' 302 0.693
DMA A-3,A-4 (BMP #2)
Area Weighted Runoff Factor (C )
Surface Type Area - A (sf) C - Factor C X A
Weighted C-
Factor
Impervious 6,973 0.90 6,276
Landscape 451 0.10 45
Gravel/DG 0 0.30 0
Total 7,424 6,321 0.851
0.17 Acres
Project: Front Porch
MWS Flow Based BMP Sizing
ITREAT = 0.2 in/hr (Intensity of rainfall)
QTREAT = C x ITREAT x A cfs (Treatment flow rate)
Design Flow (cfs) = 1.5* QTreat (Per Section F.2.2 of Storm Water Standards)
ID # Area (ac)MWS Model Selected BMP's
Flow Rate (cfs)
2 #3,4 0.17 0.85 0.03 0.044 MWS-L-4-4 0.052
Note: All selected modular wetlands treatment flow rates exceed the DMAs' design flow
BMP #DMA Runoff
Coefficient
(C )
QTREAT =
Design Flow
(cfs)
BMP Sizing
I I
WETLAN'DMEDIA I TREATMENT FLOW
MODEL# DIMENSIONS SURFACE AREA RATE
(sq. ft.) (cfs)
MWS-L-4 -4 4'x 4' 23 0.052
MWS-L-4 -6 4' X 6' 32 0.073
MWS-L-4 -8 4' x8' 50 0.115
MWS-L-4-13 4' X 13' 63 0 .144
MWS-L-4 -15 4' x 15' 76 0.175
MWS-L-4 -17 4' x 17' 90 0.206
MWS-L-4-19 4' X 19' 103 0.237
MWS-L-4 -21 4' X 21' n 1 0 .268
MWS-L-6 -8 7'x 9' 64 0 .147
MWS-L-8 -8 8' x8' 100 0.230
MWS-L-8 -1 2 8' X 12' 151 0.346
MWS-L-8 -1 6 8' x l6' 201 0.462
MWS-L-8 -20 9' X 21' 252 0.577
MWS-L-8 -24 9' X 25' 302 0.693
MWS-L-10-20 10' X 20' 302 0.693
DMA A-1 (BMP #3)
Area Weighted Runoff Factor (C )
Surface Type Area - A (sf) C - Factor C X A
Weighted C-
Factor
Impervious 2,286 0.90 2,057
Landscape 16 0.10 2
Gravel/DG 0 0.30 0
Total 2,302 2,059 0.894
0.05 Acres
Project: Front Porch
MWS Flow Based BMP Sizing
ITREAT = 0.2 in/hr (Intensity of rainfall)
QTREAT = C x ITREAT x A cfs (Treatment flow rate)
Design Flow (cfs) = 1.5* QTreat (Per Section F.2.2 of Storm Water Standards)
ID # Area (ac)MWS Model Selected BMP's
Flow Rate (cfs)
3 #1 0.05 0.89 0.01 0.014 MWS-L-4-4 0.052
Note: All selected modular wetlands treatment flow rates exceed the DMAs' design flow
BMP #DMA Runoff
Coefficient
(C )
QTREAT =
Design Flow
(cfs)
BMP Sizing
I I
WETLAN'DMEDIA I TREATMENT FLOW
MODEL# DIMENSIONS SURFACE AREA RATE
(sq. ft.) (cfs)
MWS-L-4 -4 4'x 4' 23 0.052
MWS-L-4 -6 4' X 6' 32 0.073
MWS-L-4 -8 4' x8' 50 0.115
MWS-L-4-13 4' X 13' 63 0 .144
MWS-L-4 -15 4' x 15' 76 0.175
MWS-L-4 -17 4' x 17' 90 0.206
MWS-L-4-19 4' X 19' 103 0.237
MWS-L-4 -21 4' X 21' n 1 0 .268
MWS-L-6 -8 7'x 9' 64 0 .147
MWS-L-8 -8 8' x8' 100 0.230
MWS-L-8 -1 2 8' X 12' 151 0.346
MWS-L-8 -1 6 8' x l6' 201 0.462
MWS-L-8 -20 9' X 21' 252 0.577
MWS-L-8 -24 9' X 25' 302 0.693
MWS-L-10-20 10' X 20' 302 0.693
Project: Front Porch
DMA A-2 (BMP #4)
Area Weighted Runoff Factor (C )
Surface Type Area - A (sf) C - Factor C X A Weighted C-
Factor
Impervious 3,452 0.90 3,107
LaThdscape 246 0.10 25
Gravel/DG 0 0.30 0
Total 3,698 3,131 0.847
0.08 Acres
MWS Flow Based BMP Sizing
ITREAT = 0.2 in/hr (Intensity of rainfall)
QTREAT = C x ITREAT x A cfs (Treatment flow rate)
Design Flow (cfs) = 1.5* QTreat (Per Section F.2.2 of Storm Water Standards)
BMP # DMA Runoff
Coefficient
(C )
QTREAT =
Design Flow
(cfs)
BMP Sizing
ID # Area (ac) MWS Model Selected BMP's
Flow Rate (cfs)
4 #2 0.08 0.85 0.01 0.022 MWS-L-4-4 0.052
Note: All selected modular wetlands treatment flow rates exceed the DMAs' design flow
I
WETLANDMEDIA TREATMENT FLOW
MODEL# DIMENSIONS SURFACE AREA RATE
(sq. ft.) (cfs)
MWS-L-4 -4 4' x4' 23 0.052
MWS-L-4 -6 4' X 6' 32 0.073
MWS-L-4-8 4' x8' 50 0 .11 5
MWS-L-4 -13 4' x13' 63 0.144
MWS-L-4 -15 4' X 15' 76 0 .175
MWS-L-4 -17 4' x 17' 90 0.206
MWS-L-4-19 4' X 19' 103 0.237
MWS-L-4-21 4' X 21' 117 0.268
MWS-L-6 -8 7' X 9' 64 0 .147
MWS-L-8-8 8' x8' 100 0.230
MWS-L-8 -1 2 8' X 12' 151 0.34 6
MWS-L-8 -1 6 8' x 16' 201 0.462
MWS-L-8 -20 9' X 21' 252 0.577
MWS•L-8 -24 9' X 25' 302 0.693
MWS-L-10-20 10' X 20' 302 0.693
Project: Front Porch
DMA A-6,A-7 (BMP #5)
Area Weighted Runoff Factor (C )
Surface Type Area - A (sf) C - Factor C X A Weighted C-
Factor
Impervious 5,712 0.90 5,141
LaThdscape 2,084 0.10 208
Gravel/DG 0 0.30 0
Total 7,796 5,349 0.686
0.18 Acres
MWS Flow Based BMP Sizing
ITREAT = 0.2 in/hr (Intensity of rainfall)
QTREAT = C x ITREAT x A cfs (Treatment flow rate)
Design Flow (cfs) = 1.5* QTreat (Per Section F.2.2 of Storm Water Standards)
BMP # DMA Runoff
Coefficient
(C )
QTREAT =
Design Flow
(cfs)
BMP Sizing
ID # Area (ac) MWS Model Selected BMP's
Flow Rate (cfs)
5 #6,7 0.18 0.69 0.02 0.037 MWS-L-4-4 0.052
Note: All selected modular wetlands treatment flow rates exceed the DMAs' design flow
I
WETLANDMEDIA TREATMENT FLOW
MODEL# DIMENSIONS SURFACE AREA RATE
(sq. ft.) (cfs)
MWS-L-4 -4 4' x4' 23 0.052
MWS-L-4 -6 4' X 6' 32 0.073
MWS-L-4-8 4' x8' 50 0 .11 5
MWS-L-4 -13 4' x13' 63 0.144
MWS-L-4 -15 4' X 15' 76 0 .175
MWS-L-4 -17 4' x 17' 90 0.206
MWS-L-4-19 4' X 19' 103 0.237
MWS-L-4-21 4' X 21' 117 0.268
MWS-L-6 -8 7' X 9' 64 0 .147
MWS-L-8-8 8' x8' 100 0.230
MWS-L-8 -1 2 8' X 12' 151 0.34 6
MWS-L-8 -1 6 8' x 16' 201 0.462
MWS-L-8 -20 9' X 21' 252 0.577
MWS•L-8 -24 9' X 25' 302 0.693
MWS-L-10-20 10' X 20' 302 0.693
CARLSBAD BY THE SEA SUMMER HOUSE
INF-3 Calculations
DMA B-3, BMP #6 Area (SF)C-Factor C x A Weighted C-Factor
Permeable Pavers, counted as Impervious (SF)478 0.9 430.2
Other Impervious (SF)139 0.9 125.1
Pervious (SF)219 0.1 21.9
Total (SF)836 0.690
DCV (CF) 29
Storage Area (SF)836
Depth Below Underdrain (FT)0.25
Storage Void (%)40%
Storage Volume Below Underdrain to be Infiltrated (CF)84
Storage Volume Below Underdrain to be Infiltrated > DCV YES
Infiltration Area, Permeable Paver Area without Liner (SF)81
Infiltration Rate (in/hr), per Geotech report, PT-2 0.87
Infiltration Rate (CF/hr) over Infiltration Area 5.87
Drawdown Time (hr) for Storage Volume Below Underdrain to be Infiltrated 14.24
Meets Pollutant Control Drawdown Time Requirements (<36 hours)YES
DMA B-4, BMP #7 Area (SF)C-Factor C x A Weighted C-Factor
Permeable Pavers, counted as Impervious (SF)394 0.9 354.6
Other Impervious (SF)54 0.9 48.6
Pervious (SF)282 0.1 28.2
Total (SF)730 0.591
DCV (CF)22
Aggregate Storage Area below Permeable Pavers and Landscape Areas (SF)730
Aggregate Storage Depth Below Underdrain (FT)0.25
Storage Void (%)40%
Storage Volume Below Underdrain to be Infiltrated (CF)73
Storage Volume Below Underdrain to be Infiltrated > DCV YES
Infiltration Area, Permeable Paver Area without Liner (SF)84
Infiltration Rate (in/hr), per Geotech report, PT-2 0.87
Infiltration Rate (CF/hr) over Infiltration Area 6.09
Drawdown Time (hr) for Storage Volume Below Underdrain to be Infiltrated 11.99
Meets Pollutant Control Drawdown Time Requirements (<36 hours)YES
Total Volume Infiltrated (CF)157
I I
I I
I I
I I
Category #Description i ii iii iv v vi vii viii ix x Units
1 Drainage Basin ID or Name A-1 A-2 A-3 A-4 A-5 A-6 A-7 B-3 B-4 unitless
2 85th Percentile 24-hr Storm Depth 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 inches
3 Impervious Surfaces Not Directed to Dispersion Area (C=0.90) 2,286 3,281 1,031 5,944 3,217 2,144 3,568 836 730 sq-ft
4 Semi-Pervious Surfaces Not Serving as Dispersion Area (C=0.30)sq-ft
5 Engineered Pervious Surfaces Not Serving as Dispersion Area (C=0.10)141 478 394 sq-ft
6 Natural Type A Soil Not Serving as Dispersion Area (C=0.10)sq-ft
7 Natural Type B Soil Not Serving as Dispersion Area (C=0.14) 16 297 300 16 394 2,084 358 336 sq-ft
8 Natural Type C Soil Not Serving as Dispersion Area (C=0.23)sq-ft
9 Natural Type D Soil Not Serving as Dispersion Area (C=0.30)sq-ft
10 Does Tributary Incorporate Dispersion, Tree Wells, and/or Rain Barrels? No No No No No No No No No No yes/no
11 Impervious Surfaces Directed to Dispersion Area per SD-B (Ci=0.90) sq-ft
12 Semi-Pervious Surfaces Serving as Dispersion Area per SD-B (Ci=0.30)sq-ft
13 Engineered Pervious Surfaces Serving as Dispersion Area per SD-B (Ci=0.10)sq-ft
14 Natural Type A Soil Serving as Dispersion Area per SD-B (Ci=0.10)sq-ft
15 Natural Type B Soil Serving as Dispersion Area per SD-B (Ci=0.14)sq-ft
16 Natural Type C Soil Serving as Dispersion Area per SD-B (Ci=0.23)sq-ft
17 Natural Type D Soil Serving as Dispersion Area per SD-B (Ci=0.30)sq-ft
18 Number of Tree Wells Proposed per SD-A #
19 Average Mature Tree Canopy Diameter ft
20 Number of Rain Barrels Proposed per SD-E #
21 Average Rain Barrel Size gal
22 Total Tributary Area 2,302 3,578 1,473 5,960 3,611 2,144 5,652 1,672 1,460 0 sq-ft
23 Initial Runoff Factor for Standard Drainage Areas 0.89 0.84 0.67 0.90 0.82 0.90 0.62 0.51 0.51 0.00 unitless
24 Initial Runoff Factor for Dispersed & Dispersion Areas 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 unitless
25 Initial Weighted Runoff Factor 0.89 0.84 0.67 0.90 0.82 0.90 0.62 0.51 0.51 0.00 unitless
26 Initial Design Capture Volume 102 150 49 268 148 96 175 43 37 0 cubic-feet
27 Total Impervious Area Dispersed to Pervious Surface 0 0 0 0 0 0 0 0 0 0 sq-ft
28 Total Pervious Dispersion Area 0 0 0 0 0 0 0 0 0 0 sq-ft
29 Ratio of Dispersed Impervious Area to Pervious Dispersion Area n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a ratio
30 Adjustment Factor for Dispersed & Dispersion Areas 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 ratio
31 Runoff Factor After Dispersion Techniques 0.89 0.84 0.67 0.90 0.82 0.90 0.62 0.51 0.51 n/a unitless
32 Design Capture Volume After Dispersion Techniques 102 150 49 268 148 96 175 43 37 0 cubic-feet
33 Total Tree Well Volume Reduction 0 0 0 0 0 0 0 0 0 0 cubic-feet
34 Total Rain Barrel Volume Reduction 0 0 0 0 0 0 0 0 0 0 cubic-feet
35 Final Adjusted Runoff Factor 0.89 0.84 0.67 0.90 0.82 0.90 0.62 0.51 0.51 0.00 unitless
36 Final Effective Tributary Area 2,049 3,006 987 5,364 2,961 1,930 3,504 853 745 0 sq-ft
37 Initial Design Capture Volume Retained by Site Design Elements 0 0 0 0 0 0 0 0 0 0 cubic-feet
38 Final Design Capture Volume Tributary to BMP 102 150 49 268 148 96 175 43 37 0 cubic-feet
False
False
Automated Worksheet B.1: Calculation of Design Capture Volume (V2.0)
Dispersion
Area, Tree Well
& Rain Barrel
Inputs
(Optional)
Standard
Drainage Basin
Inputs
Results
Tree & Barrel
Adjustments
Initial Runoff
Factor
Calculation
Dispersion
Area
Adjustments
No Warning Messages
Category #Description i ii iii iv v vi vii viii ix x Units
1 Drainage Basin ID or Name A-1 A-2 A-3 A-4 A-5 A-6 A-7 B-3 B-4 - unitless
2 85th Percentile Rainfall Depth 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 - inches
3 Predominant NRCS Soil Type Within BMP Location B B B B B B B B B unitless
4 Is proposed BMP location Restricted or Unrestricted for Infiltration Activities? Restricted Restricted Restricted Restricted Restricted Restricted Restricted Restricted Restricted unitless
5 Nature of Restriction Structures Structures Structures Structures Structures Structures Structures Structures Structures unitless
6 Do Minimum Retention Requirements Apply to this Project? Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes yes/no
7 Are Habitable Structures Greater than 9 Stories Proposed? No No No No No No No No No yes/no
8 Has Geotechnical Engineer Performed an Infiltration Analysis? Yes Yes Yes Yes Yes Yes Yes Yes Yes yes/no
9 Design Infiltration Rate Recommended by Geotechnical Engineer 0.870 0.870 0.870 0.870 0.870 0.870 0.870 0.870 0.870 in/hr
10 Design Infiltration Rate Used To Determine Retention Requirements 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 - in/hr
11 Percent of Average Annual Runoff that Must be Retained within DMA 4.5% 4.5% 4.5% 4.5% 4.5% 4.5% 4.5% 4.5% 4.5% - percentage
12 Fraction of DCV Requiring Retention 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 - ratio
13 Required Retention Volume 2 3 1 5 3 2 4 1 1 - cubic-feet
False
False
Automated Worksheet B.2: Retention Requirements (V2.0)
Advanced
Analysis
Basic Analysis
Result
No Warning Messages
Category #Description i ii iii iv v vi vii viii ix x Units
1 Drainage Basin ID or Name A-1 A-2 A-3 A-4 A-5 A-6 A-7 B-3 B-4 -sq-ft
2 Design Infiltration Rate Recommended 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 -in/hr
3 Design Capture Volume Tributary to BMP 102 150 49 268 148 96 175 43 37 -cubic-feet
4 Is BMP Vegetated or Unvegetated?unitless
5 Is BMP Impermeably Lined or Unlined?unitless
6 Does BMP Have an Underdrain?unitless
7 Does BMP Utilize Standard or Specialized Media?unitless
8 Provided Surface Area sq-ft
9 Provided Surface Ponding Depth inches
10 Provided Soil Media Thickness inches
11 Provided Gravel Thickness (Total Thickness)inches
12 Underdrain Offset inches
13 Diameter of Underdrain or Hydromod Orifice (Select Smallest)inches
14 Specialized Soil Media Filtration Rate in/hr
15 Specialized Soil Media Pore Space for Retention unitless
16 Specialized Soil Media Pore Space for Biofiltration unitless
17 Specialized Gravel Media Pore Space unitless
18 Volume Infiltrated Over 6 Hour Storm 0 0 0 0 0 0 0 0 0 0 cubic-feet
19 Ponding Pore Space Available for Retention 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 unitless
20 Soil Media Pore Space Available for Retention 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 unitless
21 Gravel Pore Space Available for Retention (Above Underdrain)0.40 0.40 0.40 0.40 0.40 0.40 0.40 0.40 0.40 0.40 unitless
22 Gravel Pore Space Available for Retention (Below Underdrain)0.40 0.40 0.40 0.40 0.40 0.40 0.40 0.40 0.40 0.40 unitless
23 Effective Retention Depth 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 inches
24 Fraction of DCV Retained (Independent of Drawdown Time)0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 ratio
25 Calculated Retention Storage Drawdown Time 0 0 0 0 0 0 0 0 0 0 hours
26 Efficacy of Retention Processes 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 ratio
27 Volume Retained by BMP (Considering Drawdown Time)0 0 0 0 0 0 0 0 0 0 cubic-feet
28 Design Capture Volume Remaining for Biofiltration 102 150 49 268 148 96 175 43 37 0 cubic-feet
29 Max Hydromod Flow Rate through Underdrain 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 cfs
30 Max Soil Filtration Rate Allowed by Underdrain Orifice 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 in/hr
31 Soil Media Filtration Rate per Specifications 5.00 5.00 5.00 5.00 5.00 5.00 5.00 5.00 5.00 5.00 in/hr
32 Soil Media Filtration Rate to be used for Sizing 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 in/hr
33 Depth Biofiltered Over 6 Hour Storm 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 inches
34 Ponding Pore Space Available for Biofiltration 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 unitless
35 Soil Media Pore Space Available for Biofiltration 0.20 0.20 0.20 0.20 0.20 0.20 0.20 0.20 0.20 0.20 unitless
36 Gravel Pore Space Available for Biofiltration (Above Underdrain)0.40 0.40 0.40 0.40 0.40 0.40 0.40 0.40 0.40 0.40 unitless
37 Effective Depth of Biofiltration Storage 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 inches
38 Drawdown Time for Surface Ponding 0 0 0 0 0 0 0 0 0 0 hours
39 Drawdown Time for Effective Biofiltration Depth 0 0 0 0 0 0 0 0 0 0 hours
40 Total Depth Biofiltered 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 inches
41 Option 1 - Biofilter 1.50 DCV: Target Volume 153 225 74 402 222 144 263 65 56 0 cubic-feet
42 Option 1 - Provided Biofiltration Volume 0 0 0 0 0 0 0 0 0 0 cubic-feet
43 Option 2 - Store 0.75 DCV: Target Volume 77 113 37 201 111 72 131 32 28 0 cubic-feet
44 Option 2 - Provided Storage Volume 0 0 0 0 0 0 0 0 0 0 cubic-feet
45 Portion of Biofiltration Performance Standard Satisfied 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 ratio
46 Do Site Design Elements and BMPs Satisfy Annual Retention Requirements?No No No No No No No No No -yes/no
47 Overall Portion of Performance Standard Satisfied (BMP Efficacy Factor)0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 ratio
48 Deficit of Effectively Treated Stormwater -102 -150 -49 -268 -148 -96 -175 -43 -37 n/a cubic-feet
Retention
Calculations
Automated Worksheet B.3: BMP Performance (V2.0)
False
False
BMP Inputs
Biofiltration
Calculations
-This BMP does not fully satisfy the performance standards for pollutant control for the drainage area.
False
False
False
Result
-Minimum annual retention criteria are not satisfied for each individual drainage area. Implement additional site design elements, increase structural BMP retention capacity, or demonstrate that such requirements are satisfied at the project-level.
False
Attention!
Note: Not applicable because proprietary BMPs and permeable pavement used for pollutant control in lieu of biofiltration.
Category #Description i ii iii iv v vi vii viii ix x Units
1 Drainage Basin ID or Name DMA A-1 DMA A-2 DMA A-3 DMA A-4 DMA A-5 DMA A-6 DMA A-7 DMA-B-1 DMA-B-3 DMA-B-4 unitless
2 85th Percentile 24-hr Storm Depth 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 inches
3 Is Hydromodification Control Applicable? No No No No No No No No No No yes/no
4 Impervious Surfaces Not Directed to Dispersion Area (C=0.90) 2,286 3,281 1,031 5,944 3,217 2,144 3,568 358 836 730 sq-ft
5 Semi-Pervious Surfaces Not Serving as Dispersion Area (C=0.30)sq-ft
6 Engineered Pervious Surfaces Not Serving as Dispersion Area (C=0.10)141 478 394 sq-ft
7 Natural Type A Soil Not Serving as Dispersion Area (C=0.10)sq-ft
8 Natural Type B Soil Not Serving as Dispersion Area (C=0.14) 16 297 300 16 394 0 2,084 88 358 336 sq-ft
9 Natural Type C Soil Not Serving as Dispersion Area (C=0.23)sq-ft
10 Natural Type D Soil Not Serving as Dispersion Area (C=0.30)sq-ft
11 Does Tributary Incorporate Dispersion and/or Rain Barrels? No No No No No No No No yes/no
12 Does Tributary Incorporate Tree Wells?Yes yes/no
13 Impervious Surfaces Directed to Dispersion Area per SD-B (Ci=0.90) sq-ft
14 Semi-Pervious Surfaces Serving as Dispersion Area per SD-B (Ci=0.30)sq-ft
15 Engineered Pervious Surfaces Serving as Dispersion Area per SD-B (Ci=0.10)sq-ft
16 Natural Type A Soil Serving as Dispersion Area per SD-B (Ci=0.10)sq-ft
17 Natural Type B Soil Serving as Dispersion Area per SD-B (Ci=0.14)sq-ft
18 Natural Type C Soil Serving as Dispersion Area per SD-B (Ci=0.23)sq-ft
19 Natural Type D Soil Serving as Dispersion Area per SD-B (Ci=0.30)sq-ft
20 Number of Rain Barrels Proposed per SD-E #
21 Average Rain Barrel Size gal
22 Total Tributary Area 2,302 3,578 1,472 5,960 3,611 2,144 5,652 446 1,672 1,460 sq-ft
23 Initial Runoff Factor for Standard Drainage Areas 0.89 0.84 0.67 0.90 0.82 0.90 0.62 0.75 0.51 0.51 unitless
24 Initial Runoff Factor for Dispersed & Dispersion Areas 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 unitless
25 Initial Weighted Runoff Factor 0.89 0.84 0.67 0.90 0.82 0.90 0.62 0.75 0.51 0.51 unitless
26 Initial Design Capture Volume 102 150 49 268 148 96 175 17 43 37 cubic-feet
27 Total Impervious Area Dispersed to Pervious Surface 0 0 0 0 0 0 0 0 0 0 sq-ft
28 Total Pervious Dispersion Area 0 0 0 0 0 0 0 0 0 0 sq-ft
29 Ratio of Dispersed Impervious Area to Pervious Dispersion Area for DCV Reduction n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a ratio
30 Adjustment Factor for Dispersed & Dispersion Areas 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 ratio
31 Runoff Factor After Dispersion Techniques 0.89 0.84 0.67 0.90 0.82 0.90 0.62 0.75 0.51 0.51 unitless
32 Design Capture Volume After Dispersion Techniques 102 150 49 268 148 96 175 17 43 37 cubic-feet
33 Total Rain Barrel Volume Reduction 0 0 0 0 0 0 0 0 0 0 cubic-feet
34 Final Adjusted Runoff Factor 0.89 0.84 0.67 0.90 0.82 0.90 0.62 0.75 0.51 0.51 unitless
35 Final Effective Tributary Area 2,049 3,006 986 5,364 2,961 1,930 3,504 335 853 745 sq-ft
36 Initial Design Capture Volume Retained by Dispersion Area and Rain Barrel(s) 0 0 0 0 0 0 0 0 0 0 cubic-feet
37 Remaining Design Capture Volume Tributary to Tree Well(s) 102 150 49 268 148 96 175 17 43 37 cubic-feet
False
False
SSD-BMP Automated Worksheet I-1: Step 1. Calculation of Design Capture Volume (V1.0)
Standard
Drainage Basin
Inputs
Results
No Warning Messages
Dispersion Area
Adjustment &
Rain Barrel
Adjustment
SSD-BMPs
Proposed
Dispersion Area
& Rain Barrel
Inputs
(Optional)
Initial Runoff
Factor
Calculation
False
ONSITE
Category #Description i ii iii iv v vi vii viii ix x Units
1 Drainage Basin ID or Name DMA A-1 DMA A-2 DMA A-3 DMA A-4 DMA A-5 DMA A-6 DMA A-7 DMA-B-1 DMA-B-3 DMA-B-4 unitless
2 85th Percentile 24-hr Storm Depth 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 inches
3 Is Hydromodification Control Applicable? No No No No No No No No No No yes/no
4 Impervious Surfaces Not Directed to Dispersion Area (C=0.90) 2,286 3,281 1,031 5,944 3,217 2,144 3,568 358 836 730 sq-ft
5 Semi-Pervious Surfaces Not Serving as Dispersion Area (C=0.30)sq-ft
6 Engineered Pervious Surfaces Not Serving as Dispersion Area (C=0.10)141 478 394 sq-ft
7 Natural Type A Soil Not Serving as Dispersion Area (C=0.10)sq-ft
8 Natural Type B Soil Not Serving as Dispersion Area (C=0.14) 16 297 300 16 394 0 2,084 88 358 336 sq-ft
9 Natural Type C Soil Not Serving as Dispersion Area (C=0.23)sq-ft
10 Natural Type D Soil Not Serving as Dispersion Area (C=0.30)sq-ft
11 Does Tributary Incorporate Dispersion and/or Rain Barrels? No No No No No No No No yes/no
12 Does Tributary Incorporate Tree Wells?Yes yes/no
13 Impervious Surfaces Directed to Dispersion Area per SD-B (Ci=0.90) sq-ft
14 Semi-Pervious Surfaces Serving as Dispersion Area per SD-B (Ci=0.30)sq-ft
15 Engineered Pervious Surfaces Serving as Dispersion Area per SD-B (Ci=0.10)sq-ft
16 Natural Type A Soil Serving as Dispersion Area per SD-B (Ci=0.10)sq-ft
17 Natural Type B Soil Serving as Dispersion Area per SD-B (Ci=0.14)sq-ft
18 Natural Type C Soil Serving as Dispersion Area per SD-B (Ci=0.23)sq-ft
19 Natural Type D Soil Serving as Dispersion Area per SD-B (Ci=0.30)sq-ft
20 Number of Rain Barrels Proposed per SD-E #
21 Average Rain Barrel Size gal
22 Total Tributary Area 2,302 3,578 1,472 5,960 3,611 2,144 5,652 446 1,672 1,460 sq-ft
23 Initial Runoff Factor for Standard Drainage Areas 0.89 0.84 0.67 0.90 0.82 0.90 0.62 0.75 0.51 0.51 unitless
24 Initial Runoff Factor for Dispersed & Dispersion Areas 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 unitless
25 Initial Weighted Runoff Factor 0.89 0.84 0.67 0.90 0.82 0.90 0.62 0.75 0.51 0.51 unitless
26 Initial Design Capture Volume 102 150 49 268 148 96 175 17 43 37 cubic-feet
27 Total Impervious Area Dispersed to Pervious Surface 0 0 0 0 0 0 0 0 0 0 sq-ft
28 Total Pervious Dispersion Area 0 0 0 0 0 0 0 0 0 0 sq-ft
29 Ratio of Dispersed Impervious Area to Pervious Dispersion Area for DCV Reduction n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a ratio
30 Adjustment Factor for Dispersed & Dispersion Areas 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 ratio
31 Runoff Factor After Dispersion Techniques 0.89 0.84 0.67 0.90 0.82 0.90 0.62 0.75 0.51 0.51 unitless
32 Design Capture Volume After Dispersion Techniques 102 150 49 268 148 96 175 17 43 37 cubic-feet
33 Total Rain Barrel Volume Reduction 0 0 0 0 0 0 0 0 0 0 cubic-feet
34 Final Adjusted Runoff Factor 0.89 0.84 0.67 0.90 0.82 0.90 0.62 0.75 0.51 0.51 unitless
35 Final Effective Tributary Area 2,049 3,006 986 5,364 2,961 1,930 3,504 335 853 745 sq-ft
36 Initial Design Capture Volume Retained by Dispersion Area and Rain Barrel(s) 0 0 0 0 0 0 0 0 0 0 cubic-feet
37 Remaining Design Capture Volume Tributary to Tree Well(s) 102 150 49 268 148 96 175 17 43 37 cubic-feet
False
False
SSD-BMP Automated Worksheet I-1: Step 1. Calculation of Design Capture Volume (V1.0)
Standard
Drainage Basin
Inputs
Results
No Warning Messages
Dispersion Area
Adjustment &
Rain Barrel
Adjustment
SSD-BMPs
Proposed
Dispersion Area
& Rain Barrel
Inputs
(Optional)
Initial Runoff
Factor
Calculation
False
ONSITE
Category #Description i ii iii iv v vi vii viii ix x Units
1 Drainage Basin ID or Name ---------- unitless
2 Final Design Capture Volume (DCV) ---------- cubic-feet
3 Is Hydromodification Control Applicable? ---------- yes/no
4 Total Impervious Area Dispersed to Pervious Surface ---------- sq-ft
5 Total Engineered Pervious Surface and/or Natural Soil Dispersion Area
(Does Not Include Semi-Pervious Surfaces Serving as Dispersion Area)---------- sq-ft
6 Ratio of Dispersed Impervious Area to
Total Engineered Pervious Surface and/or Natural Soil Dispersion Area ---------- unitless
7 Dispersion Area Length (Length of Sheet Flow Across Dispersion Area)feet
8 Dispersion Area Slope %
9 Thickness of Amended Soil inches
10 How is Flow Dispersed Across Width of Dispersion Area (definitions below*)?unitless
11 Is DCV Requirement Fully Satisfied by Dispersion Area? ---------- yes/no
12 Is Hydromodification Control Requirement Satisfied by Dispersion Area? ---------- yes/no
13 Are Dispersion Area Length, Slope, and Thickness of Amended Soil (when applicable) Adequate? ---------- yes/no
Notes:
*How is Flow Dispersed Across Width of Pervious Dispersion Area?
Sheet Flow: Flow arrives as sheet flow across the width of the adjacent impervious area
Spreader(s): Flow is discharged from flow spreader(s) across the width of the pervious area
Roof Drains: Discharge from roof drains distributed across the width of the pervious area
Curb Cuts: Discharge from curb cuts distributed across the width of the pervious area
Other:Other (Describe in PDP SWQMP)
SSD-BMP Automated Worksheet I-2: Step 2. Dispersion Area Validation (V1.0)
False
False
False
False
No Warning Messages
False
False
Standard
Dispersion Area
Inputs
Results
Note: Dispersion areas are not claimed on this project as project volume retention is larger
than target volume retention required by City of San Diego Worksheet B-5.6. Retention
requirements are met by using permeable pavement.
ONSITE
Category #Description i ii iii iv v vi vii viii ix x Units
1 Drainage Basin ID or Name DMA A-1 DMA A-2 DMA A-3 DMA A-4 DMA A-5 DMA A-6 DMA A-7 DMA-B-1 DMA-B-3 DMA-B-4 unitless
2 Design Capture Volume Tributary to BMP 102 150 49 268 148 96 175 17 43 37 cubic-feet
3 Is Hydromodification Control Applicable? No No No No No No No No No No yes/no
4 Predominant NRCS Soil Type Within Tree Well(s) Location B B B B B B B B unitless
5 Select a Tree Species for the Tree Well(s) Consistent with SD-A Tree Palette Table
Note: Numbers shown in list are Tree Species Mature Canopy Diameters 10' - Other unitless
6 Tree Well(s) Soil Depth (Installation Depth)
Must be 30, 36, 42, or 48 Inches; Select from Standard Depths**36 inches
7 Number of Identical* Tree Wells Proposed for this DMA 1 trees
8 Proposed Width of Tree Well(s) Soil Installation for One (1) Tree 8.0 feet
9 Proposed Length of Tree Well(s) Soil Installation for One (1) Tree 8.0 feet
10 Botanical Name of Tree Species -------Provide in PDP
SWQMP -- unitless
11 Tree Species Mature Height per SD-A -------Provide in PDP
SWQMP -- feet
12 Tree Species Mature Canopy Diameter per SD-A -------10 -- feet
13 Minimum Soil Volume Required In Tree Well
(2 Cubic Feet Per Square Foot of Mature Tree Canopy Projection Area)-------157 -- cubic-feet
14 Credit Volume Per Tree -------40 -- cubic-feet
15 DCV Multiplier To Meet Flow Control Requirements -------n/a -- unitless
16 Required Retention Volume (RRV) To Meet Flow Control Requirements -------n/a -- cubic-feet
17 Number of Trees Required -------1 -- trees
18 Total Area of Tree Well Soil Required for Each Tree -------52 -- sq-ft
19 Approximate Required Width of Tree Well Soil Area for Each Tree -------8 -- feet
20 Approximate Required Length of Tree Well Soil Area for Each Tree -------8 -- feet
21 Number of Trees Proposed for this DMA -------1 -- trees
22 Total Area of Tree Well Soil Proposed for Each Tree -------64 -- sq-ft
23 Minimum Spacing Between Multiple Trees To Meet Soil Area Requirements
(when applicable)***-------n/a -- feet
24 Are Tree Well Soil Installation Requirements Met?Incomplete Incomplete Incomplete Incomplete Incomplete Incomplete Incomplete Yes Incomplete Incomplete yes/no
25 Is Remaining DCV Requirement Fully Satisfied by Tree Well(s)?Incomplete Incomplete Incomplete Incomplete Incomplete Incomplete Incomplete Yes Incomplete Incomplete yes/no
26 Is Hydromodification Control Requirement Satisfied by Tree Well(s)?n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a yes/no
Notes:
*If using more than one mature canopy diameter within the same DMA, only the smallest mature canopy diameter should be entered. Alternatively, if more than one mature canopy diameter is proposed and/or the dimensions of multiple tree well installations will vary, separate DMAs may be delineated.
**If the actual proposed installation depth is not available in the table of standard depths, select the next lower depth.
***Tree Canopy or Agency Requirements May Also Influence the Minimum Spacing of Trees.
False
False
False
False
SSD-BMP Automated Worksheet I-3: Step 3. Tree Well Sizing (V1.0)
False
-[Line 12] Applicant to provide supporting documentation for tree species in PDP SWQMP.
Standard Tree
Well Inputs
Attention!
Tree Data
Tree Well Sizing
Calculations
Results
Note: DMA A-1 through A-7 and DMA B-3 and B-4 are shown as incomplete because there are no tree wells utilized in these DMAs.
ONSITE
DMAs A-1 through A-7, B-3, B-4
Area Weighted Runoff Factor (C )
Surface Type Area - A (sf) C - Factor C X A
Weighted C-
Factor
Impervious 24,050 0.90 21,645
Landscape 3,801 0.10 380
Gravel/DG 0 0.30 0
Total 27,851 22,025 0.791
0.64 Acres
Project: Front Porch
Project Name
BMP ID
1 27851 sq. ft.
2 0.791
3 0.6 inches
4 1102 cu. ft.
5 0.05 in/hr.
6 2
7 0.025 in/hr.
10 82 cu. ft.
When Line 8 > 8% =
0.0000013 x Line 83 - 0.000057 x Line 82 + 0.0086 x Line 8 - 0.014
When Line 8 ≤ 8% = 0.023
Target volume retention [Line 9 x Line 4]
Reliable infiltration rate, for biofiltration BMP sizing [Line 5 / Line 6]
8
Average annual volume reduction target (Figure B.5-2)
10.8
9
Fraction of DCV to be retained (Figure B.5-3)
0.074
%When Line 7 > 0.01 in/hr. = Minimum (40, 166.9 x Line 7 +6.62)
When Line 7 ≤ 0.01 in/hr. = 3.5%
Factor of safety
Area draining to the BMP
Carlsbad By the Sea
DMAs A-1 through 7, B-3, B-4 - Restricted Condition
Sizing Method for Volume Retention Criteria Worksheet B.5-2
Adjusted runoff factor for drainage area (Refer to Appendix B.1 and B.2)
85th percentile 24-hour rainfall depth
Design capture volume [Line 1 x Line 2 x (Line 3/12)]
Volume Retention Requirement
Measured infiltration rate in the DMA
Note:
When mapped hydrologic soil groups are used enter 0.10 for NRCS Type D soils and for
NRCS Type C soils enter 0.30
When in no infiltration condition and the actual measured infiltration rate is unknown
enter 0.0 if there are geotechnical and/or groundwater hazards identified in Appendix C
Project Name
BMP ID
1 sq. ft.
2
3 sq. ft.
4 sq. ft.
5 sq. ft.
Identification 1 4 5
6
7
10 sq. ft.
11 sq. ft.
12
13
14 cu. ft.
15 cu. ft.
Identification
1 cu. ft.
2 cu. ft.
3 cu. ft.
4 cu. ft.
5 cu. ft.
cu. ft.
17
Area draining to the biofiltration BMP 27851
Carlsbad By the Sea Summer House
Permeable Pavers
Volume Retention for No Infiltration Condition Worksheet B.5-6
Landscape area that meet the requirements in SD-B and
SD-F Fact Sheet (sq. ft.)
Adjusted runoff factor for drainage area (Refer to Appendix B.1 and B.2)0.791
Effective impervious area draining to the BMP [Line 1 x Line 2]22030
Required area for Evapotranspiration [Line 3 x 0.03]661
Biofiltration BMP Footprint 0
Landscape Area (must be identified on DS-3247)
2 3
Impervious area draining to the landscape area (sq. ft.)
8 Impervious to Pervious Area ratio 0.00 0.00 0.00
Volume Retention Performance Standard
0.00 0.00[Line 7/Line 6]
9 Effective Credit Area 0 0 0 0 0If (Line 8 >1.5, Line 6, Line 7/1.5]
Sum of Landscape area [sum of Line 9 Id’s 1 to 5]0
Provided footprint for evapotranspiration [Line 5 + Line 10]0
Is Line 11 ≥ Line 4?No, Proceed to Line 13
Fraction of the performance standard met through the BMP footprint and/or landscaping
[Line 11/Line 4]0
Target Volume Retention [Line 10 from Worksheet B.5.2] 82
16
Permeable Pavers (Area = 165 SF, See INF-3 Calcs)157
Sum of volume retention benefits from other site design BMPs (e.g. trees; rain barrels etc.).
[sum of Line 16 Credits for Id’s 1 to 5]
Provide documentation of how the site design credit is calculated in the PDP SWQMP.
157
Volume retention required from other site design BMPs
[(1-Line 13) x Line 14]82
Site Design BMP
Site Design Type Credit
Is Line 16 ≥ Line 15?Volume Retention Performance Standard is Met
SD SD SDSDSDSD
SD
SD
SD
SD
SD
SD
SD
SD
SD SD SD SD SD
S
D
SD
SD SD SD SD SD SD SD
SD
SD
SD
SD
SD
SD
S
D
S S S S S S S S S S S S S S S
S S S S S S S S S S S S S S S
W W W W W W W W W W W W W WW
W
W
W
W
W
W
W
W
W
W
WWWW
SS S
OHE
OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE
OHE
OHE
S
W
W
W
W
W
W
W
W
W
FW
FW
S S
IRRG IRRG IRRG IRRG IRRG IRRG IRRG IRRG
FF 51.75
FF 42.50FF 51.75
FF 42.50
A-5A-5
10
.
0
0
'
10
.
0
0
'
W
W
EC
51
51
51
50
34
35
36
37
38
39
40
41
42
43
9449 BALBOA AVE, STE 270
SAN DIEGO, CA 92123 619.299.5550BWE JOB NO. 13913US1.00
ENGINEERING DEPARTMENT
2710, 2720, 2730, & 2740 OCEAN STREET
CARLSBAD, CA. 92008
MATCHLINE SHEET 2
MA
T
C
H
L
I
N
E
S
H
E
E
T
2
PROPOSED TREE WELL #1
SOIL VOLUME = 1,008 CF
PROPOSED TREE WELL #2
SOIL VOLUME = 192 CF
TREE WELL #1 SOIL VOLUME ANALYSIS
TOTAL DISTURBED AREA (INCLUDING AREAS TO BE OFFSET) = OFF-1 + OFF-2 + OFF-3+ OFF-4 =
=0.053+0.035+0.023+0.033 = 0.144 ACRES = 6,261 SF
IMPERVIOUS AREA = 4,844 SF
PERVIOUS AREA = 1,417 SF
EFF. IMPERVIOUS AREA = 4,844 SF + (1,417 SF * 0.1) = 4,986 SF
AREA TREATED BY TREE WELL #1 = OFF-3 + EXCESS OFFSITE AREA = 1,015 SF + 5,490 SF = 6,505 SF
IMPERVIOUS AREA = 5,916 SF
PERVIOUS AREA = 589 SF
EFF. IMPERVIOUS AREA = 5,916 SF + (589 SF * 0.1) = 5,975 SF
MIN. SOIL VOLUME REQUIRED = 982 CF
(REFER TO WORKSHEET I-3 (OFFSITE) IN ATTACHMENT 1E - POLLUTANT CONTROL SIZING)
PROVIDED SOIL VOLUME = 14'x18'x4' = 1,008 CF
TREE WELL #1 DRAWDOWN TIMES
INFILTRATION RATE = 0.87 IN/HR
DCV = 270 CF
14 FT * 18 FT = 252 SF * 0.87 IN/HR (1FT/12IN) * 36 HOURS = 657 CF > 270 CF
BMP MEETS THE DRAWDOWN REQUIREMENTS OF 36 HOURS
NOTE:
25' CANOPY FOR TREE WELL #1
10' CANOPY FOR TREE WELL #2
48" DEEP STRUCTURAL SOIL FOR TREE WELL #1
36" DEEP STRUCTURAL SOIL FOR TREE WELL #2
BOTH TREE WELLS AREA LINED ON THE SIDES.
TREE WELL #2 CONTAINS A SUBDRAIN PER
GEOTECHNICAL RECOMMENDATIONS.
TREE WELL #2 SOIL VOLUME ANALYSIS
TOTAL AREA TREATED BY TREE WELL #2 (INCLUDING AREAS TO BE OFFSET) = 0.010 ACRES = 446 SF
IMPERVIOUS AREA = 358 SF
PERVIOUS AREA = 88 SF
EFF. IMPERVIOUS AREA = 446 + (88 SF * 0.1) = 455 SF
MIN. SOIL VOLUME REQUIRED = 157 CF
(REFER TO WORKSHEET I-3 (ONSITE) IN ATTACHMENT 1E - POLLUTANT CONTROL SIZING)
PROVIDED SOIL VOLUME = 8'x8'x3' = 192 CF > 157 CF
TREE WELL #2 DRAWDOWN TIMES
INFILTRATION RATE = 0.87 IN/HR
DCV = 17 CF
8 FT * 8 FT = 64 SF * 0.87 IN/HR(1FT/12IN) * 36 HOURS = 167 CF > 17 CF
BMP MEETS THE DRAWDOWN REQUIREMENTS OF 36 HOURS
C
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--.,.:14-.::D.:..:W.::G.:... • ....:1..::8:::8-_9,~1_9_3-_1 ---I--
_}.\·+ ---------
Siting and Design
Improvement
Traffic Signal, Swp sign
Underground U ti licy tines
( except sewer)
Sewer fJnes
Above ground utility
structures (Transformers,
Hydrants, Utility poles, etc.)
Drlvewn.ys
I ntersections. (intersecting
curb lines o f two streets)
Minim um
di stance to
Tree Well
20 feet
5 feet
10 feet
10 fee t
10 feet
25 fee t
ROOF
LINE
TYP
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BACKYARD
DRAINS
BMP #1
10300FS
rt
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-_, - -_,_
(PRIVAlE
BACKYARD I
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---_________ .. ___________________________________ --------------
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BUILDIN w BASEMENT
VARIES F=33.0
100.00FS
~ .
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E-MINIMIS
DMA
46 I
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\==-:::::::'....==' ~~ :....:..· .=...:....:...==-J.
,£--;,, BMP IJ6 PERMEABLE PAYERS (478 SF
Vi_ r4fi~~rWrJY1~Y¥6~f/i~~~~~N 38.9
38.7
OCEAN £TREET
~ INFEASIBILITY STUDY ----;.~-+
__ A_s_P-~H~. ~&~lfri rd MAIN_ .. ■------
b!l,·+ AREA b!l,· +
/
5 0 10 B\V E
20 CIVIL •STRUCTURAL•SURVEY• PLANNING
SCALE IN FEET
1 inch = 10 ft.
1
DATE INITIAL
ENGINEER OF WORK
EXISTING BUILI
/
SMH
4. .33RI
.651E
RFPI ACTD-
SICE.l'V,.;l I<
F:OOT C01'HROL
BARRIER PER
SDRSD L-05
/-iFJ f,111
P _.ASTIC
LI, ER
SECTION B•B
/-LIVITS OF ROCTING S8IL
/ PER CESIG l,J PLANS
/ REPLACE SIDE•/1/A U< AS
i' NE 2ESS/\R"' FOR EXP/\hDE
/ STRUC TUF:A.L S:)IL \IOLU\t1E
~A
J
cuFB a G1JTTERJ
PER SCRSD C-02
18"' WIDE CIJRBY_/':>TREET'._ ___ .--"----SPLAS---j P1~.D ~-30 MIL
r LA S-IC
LINUS:: CL.T 7 ER GS-.S.01 PER GS-.5.C,6
#4x8" SMOOTH-....._
oowcLs @ -e" o_c, \ I
GRE ASED_ Gr\J ?\JE __ El'-JD_ \
E'.l"TIN-. TYP . ALL '.:>IDC) 1
I' _, 1-' -1 I
SIDEWALi< \ \
J>. _,. _;,-·.-., ... / /
~CYLACi:.. '.:ill.llW,AU<--
AS l'-IECESSA~Y
FO~ EXPAr\J DED
STRUCTU~AL SOIL
\IO LU \I E
NOTES:
PLAN VIEW
SECTION A-A
/-EXP/1NSION JOlrH,
/ TYP . ALL SI DES /
/' (-INSTALL 3,:=; \1 IL l'LAST C
LI I\ER ',VHERE CONCRETE I':,
/ '1 POU i?[D 0\1[1~ STmlCTUR.4L
1 SOIL (JYP.)
\_S1\N) FILTER
LAYER
--I ,, ,' <
\,• ...... 30 ~✓I L
PLAS TIC
LIN ER
1. REFER TO GS-1.0'.) FOR ALL DETAILS ~~OT SHOWN HERE
2. TREE SIZE & TvPE PER DESI GN PL:\NS_ DRAWING NOT TO SCALE
RE·.,1s mis 1-PPR(,•.rnI )~.Tr DrVi'.',N JY .f:illL Cl nm.1 CY: ___EE_ SAN DIEGO COUNT Y DE SIGN STANDARJ
,,__-,-•f<CV[[) J·· CCIJ\ TY UliT·l[=R
r 'ltvlll') L'1;\T 1 0/1..,J,.._
',Ui,1,1,1 P. \lO'i:G; , P.E.
R.:.E ~IC. 49452, ~XP 9/30/21)20
DATE INITIAL DATE
LARGE TREE
WELL
0I\IGIN.t..L 10-01-201•~
DRAWl~G GS-1.02 NUM B=:R
TREE WELL EXHIBIT
[2]1 CITY OF CARLSBAD I[!]
FRONT PORCH MEMORY CAFE AND IIIDEPENDENT LIVING
INITIAL
REVISION DESCRIPTION OTHER APPROVAL CITY APPROVAL
SD
W
W
W
S
S
S
S
S S SS
OHE
OHE
OHE
OH
E
OH
E
OH
E
OH
E
OH
E
OHE OHE OHE
W W
W
W
W
W
S
S
S
S
S
S
S
S
S
S
S
W
W
W
W
W
W
W
S S S
W
51
9449 BALBOA AVE, STE 270
SAN DIEGO, CA 92123 619.299.5550BWE JOB NO. 13913US1.00
ENGINEERING DEPARTMENT
2710, 2720, 2730, & 2740 OCEAN STREET
CARLSBAD, CA. 92008
MATCHLINE SHEET 1
MA
T
C
H
L
I
N
E
S
H
E
E
T
1
C
L
=
C
c:
Q_
I
I
I
I
I " I ~~-
I
I
I
I
I
I
I
I
I ~ I ~~-..
I
I
I
I
I
I ~I
52 CONC
ENCASED
I< SWR
~'-·+
REQUIRED IMPERVIOUS AREA = OFF-1 + OFF-2 + OFF-4 = 0.053 + 0.035 + 0.014 = 0.102 ACRE = 4,418 SF
EXCESS IMPERVIOUS AREA = 5,490 SF
5,490 SF > 4,418 SF
G27i)
P1,.ER DWG 195-
-
~-r
!SD-K!
SIDEW1\~-K .•. -, _ · .. · 1/ ~l~~iTIC ~-.. _ _ ,,.--0'::Ei' RO:JT
REPLACE~D-,-3U '1 L
> • • I _.,...,-TREE BJBBLER
/ RCOT C:Jh TROL-/ PCR SDf\SD l-•J4
81\R~IER PER / ,, SDRSD L-05 / ---~4x2 9,100TH
SECTION B-B ,/ / om•,'ELS @ 18" O.C,
/ GRE1\SEJ ON ONE END,
EXPN~s1or~ JOINTS,--,/ (1 TYP. ALL 3 s 1cEs
TYF ALL 3 SID ES \ U 7 , ---___ / )' .---Ll:V'IT:~; 01 ROC TlhK :)CIL
ADHERE LI NER~ p /''v-.\ _.,....----_,,----~ // --·i..._ 11./ / PER DESIGl,J FL:'.\f\S TJ u 1~11-s OF , 1 1 \ _ _.., ',. / ' ·,. \' , I , ,1 I REl-'L/\CE '..:i UE'WAU< N3
;:EPLA.CEO 1 \ BACi< OF ,-1 ~• ',-J / )"'// OJ NE'.:ESSA.RY FOR EXPAI\I DED
Slr:JF\IVAI K \ \ EX. SIDEW/-.LK /, 1 u TYP /-1 /' li STR UCTURAL SCIL \iOLU~1E
A
~
GS-1 J2
(_)~ -~ ~~ l/l lL X e w [7:
j
\
I STREET
CU RB & GUr ER-1
PE~ SDRSD G-02
30 MIL
P _,~.ST C Uts.J ER
NOTES:
'·~ROJT cmrROL
BJ'..RRIER l'ER
SDRSC L-:Jl:3
u J ·.._s )E\'/A. LI< .Ui'JO::RC1RJl.li'J
r ER GS -5 04
TYP E PER: DESIGt'-1 PLANS
PLAN VIEW
SECTION C-C
F:OOT
RAI I
REFER TO GS-' .00 FOR ;.,_L DE TAILS f'.lOT SHOWN HER E
2. TREE SIZE & TY::iE PEF: DESIGt~ PLAi'lS.
A=rnc•/~D BY COU1/h rnCIME=r
W (' "httdl fiD.ii.T[: lo /1""/l"'I
\'l'ILLF•M P. ~IGRC7n.
R.C.t::. f:D. 49452, ::XP 9/30/21)20
SAi, DIEGO COU N-Y DESIGN STAl,DA~D
TREE WELL ADJACENT
TO RIGHT-OF-WAY
~,O r•,I IL
PL 4"::,TIC
LI f\ ER
(-30 MIL
--'L/\STIC
\J FR
#4 @ 18" o.c.
BDTf-''NA.YS
'
'\_s,\ND FILTER
I A.YFR
DRAWING NOT TO SCALE
RE '!l],:t-.S 1~.FPR·Y/ED DATE
ORIGll'-l t..L 10-Dl-20IS
DR,\WING
t,UM EcR GS-1.03
5 0 10
SCALE IN FEET
1 inch = 10 ft.
NOTES:
7" TC 4"
GUTER DEFRESSION
(FER PLANS)
S:::E NO TE 4
SECTION B-B
I. CONC=?E TE SHA.LL BE 56J-C-32SD
Tl IIS TY='[ ,Jf D[SIC\J CAN CONf'J [C T TO
& Ac,:..:u.H.Wllti, IC. ANY IYl--'C. ,:_:,r ::ll\.11--'.
PLAN
PFF? ='I A\JS, 10'-c," MAX.
_//L @ 6" 0 .C
BOTH We."S r, PER
C:JNrn~uous 1 \
ELE'/.
PL,~.1'JS \ n
(TYP.) \
ANCHOR DETAIL
2 SEC T J r~ TO 3E SLOPE D LA.TERA1LY WHH TOP CO~JFO~MING TO ::::RACES OF THE E:X:IS7 r-)G SID:::WALK & CURB.
j TROWE L FINISH TOP SURF1\2E & F _00=? OU TEL T. REPRODUCE M1\R-<:l~~GS OF EXISTlf✓G SIDEWALK ,ll.1-.J D CURB.
4 OPEl\II [,JG '1','IOTHS 'J EXCE'.3S OF 2:,-FT (TO cor-.JVEY THE l :J-YR STORM E\'DH) S·-iAL_ F~EQUIRE APPF!OVED
STR UCTUf?AL C.4LCJL . .:O.TIDr-.JS
5 GU TTER TRANSITIO I-.J _:::NG TH PER DE SIGN Plf'NS: AN ."-.DDITIO'JA_ 2.'.:,-FT CURB TRAI-.JSITION LENGTH IS
RECOMMD,]ED FCR EVERY 1" OF ,'\DD TIUt-.J ,'.\L GUTTER DEF1R:::':.:Sl(J-.J
6 ELEV,'\TICl'J'.:: SHALL BE SHC',NI\ ON PLM~S \ty'HERE INDIC.i\TED EY "o " SY~·1BOL.
rm;;'A,-.1 JY:...6!2L I 'i HFcu ~, R"r: Rr
l<D '.tl',,l[Nfl[[J GY: 1J-1.~RLES MOHRLOCK, P.E
SAN DIEGO COUN TY DESIGN STANDARJ
w (' "httdl~c,,n: lO/l~,,"'I
\\1LLIM~ P MORG~.
R.C.E. NO. 49452, D:P 9/J0/2020
/
B\V E
20 CIVIL •STRUCTURAL•SURVEY• PLANNING
SIDEWALK
UNDERDRAIN
DATE INITIAL
ENGINEER OF WORK
DRAWING NOT TO SCALE
ORIGINP.L 10-C1-2Cl9
I ' I
DR1\Wll,GGS 5 04 t,UM3ER " , a
REVISION DESCRIPTION
TREE WELL EXHIBIT
01 CITY OF CARLSBAD I[!]
FRONT PORCH MEMORY CAFE AND IIIDEPENDENT LIVING
DATE INITIAL DATE INITIAL
OTHER APPROVAL CITY APPROVAL
Category #Description i ii iii iv v vi vii viii ix x Units
1 Drainage Basin ID or Name TREE WELL 1: EXCESS AREA, DMA-3 (PROVIDED) OFF-1,2,3,4 (REQUIRED)OFF-1 OFF-2 OFF-3 OFF-4 EXCESS AREA unitless
2 85th Percentile 24-hr Storm Depth 0.60 0.60 0.60 0.60 0.60 0.60 0.60 inches
3 Is Hydromodification Control Applicable?No No No No No No No yes/no
4 Impervious Surfaces Not Directed to Dispersion Area (C=0.90) 5,916 4,844 2,309 1,512 426 597 5,490 sq-ft
5 Semi-Pervious Surfaces Not Serving as Dispersion Area (C=0.30)sq-ft
6 Engineered Pervious Surfaces Not Serving as Dispersion Area (C=0.10)sq-ft
7 Natural Type A Soil Not Serving as Dispersion Area (C=0.10)sq-ft
8 Natural Type B Soil Not Serving as Dispersion Area (C=0.14)589 1,417 0 0 589 828 0 sq-ft
9 Natural Type C Soil Not Serving as Dispersion Area (C=0.23)sq-ft
10 Natural Type D Soil Not Serving as Dispersion Area (C=0.30)sq-ft
11 Does Tributary Incorporate Dispersion and/or Rain Barrels? No No No No No No No yes/no
12 Does Tributary Incorporate Tree Wells?yes/no
13 Impervious Surfaces Directed to Dispersion Area per SD-B (Ci=0.90) sq-ft
14 Semi-Pervious Surfaces Serving as Dispersion Area per SD-B (Ci=0.30)sq-ft
15 Engineered Pervious Surfaces Serving as Dispersion Area per SD-B (Ci=0.10)sq-ft
16 Natural Type A Soil Serving as Dispersion Area per SD-B (Ci=0.10)sq-ft
17 Natural Type B Soil Serving as Dispersion Area per SD-B (Ci=0.14)sq-ft
18 Natural Type C Soil Serving as Dispersion Area per SD-B (Ci=0.23)sq-ft
19 Natural Type D Soil Serving as Dispersion Area per SD-B (Ci=0.30)sq-ft
20 Number of Rain Barrels Proposed per SD-E #
21 Average Rain Barrel Size gal
22 Total Tributary Area 6,505 6,261 0 2,309 1,512 1,015 1,425 5,490 0 0 sq-ft
23 Initial Runoff Factor for Standard Drainage Areas 0.83 0.73 0.00 0.90 0.90 0.46 0.46 0.90 0.00 0.00 unitless
24 Initial Runoff Factor for Dispersed & Dispersion Areas 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 unitless
25 Initial Weighted Runoff Factor 0.83 0.73 0.00 0.90 0.90 0.46 0.46 0.90 0.00 0.00 unitless
26 Initial Design Capture Volume 270 229 0 104 68 23 33 247 0 0 cubic-feet
27 Total Impervious Area Dispersed to Pervious Surface 0 0 0 0 0 0 0 0 0 0 sq-ft
28 Total Pervious Dispersion Area 0 0 0 0 0 0 0 0 0 0 sq-ft
29 Ratio of Dispersed Impervious Area to Pervious Dispersion Area for DCV Reduction n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a ratio
30 Adjustment Factor for Dispersed & Dispersion Areas 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 ratio
31 Runoff Factor After Dispersion Techniques 0.83 0.73 n/a 0.90 0.90 0.46 0.46 0.90 n/a n/a unitless
32 Design Capture Volume After Dispersion Techniques 270 229 0 104 68 23 33 247 0 0 cubic-feet
33 Total Rain Barrel Volume Reduction 0 0 0 0 0 0 0 0 0 0 cubic-feet
34 Final Adjusted Runoff Factor 0.83 0.73 0.00 0.90 0.90 0.46 0.46 0.90 0.00 0.00 unitless
35 Final Effective Tributary Area 5,399 4,571 0 2,078 1,361 467 656 4,941 0 0 sq-ft
36 Initial Design Capture Volume Retained by Dispersion Area and Rain Barrel(s)0 0 0 0 0 0 0 0 0 0 cubic-feet
37 Remaining Design Capture Volume Tributary to Tree Well(s)270 229 0 104 68 23 33 247 0 0 cubic-feet
False
False
SSD-BMP Automated Worksheet I-1: Step 1. Calculation of Design Capture Volume (V1.0)
Standard
Drainage Basin
Inputs
Results
No Warning Messages
Dispersion Area
Adjustment &
Rain Barrel
Adjustment
SSD-BMPs
Proposed
Dispersion Area
& Rain Barrel
Inputs
(Optional)
Initial Runoff
Factor
Calculation
False
OFF-SITE
Category #Description i ii iii iv v vi vii viii ix x Units
1 Drainage Basin ID or Name TREE WELL 1: EXCESS AREA, DMA-3 (PROVIDED) OFF-1,2,3,4 (REQUIRED)-OFF-1 OFF-2 OFF-3 OFF-4 EXCESS AREA -- unitless
2 Design Capture Volume Tributary to BMP 270 229 -104 68 23 33 247 --cubic-feet
3 Is Hydromodification Control Applicable?No No -No No No No No -- yes/no
4 Predominant NRCS Soil Type Within Tree Well(s) Location B B B B B B B B unitless
5 Select a Tree Species for the Tree Well(s) Consistent with SD-A Tree Palette Table
Note: Numbers shown in list are Tree Species Mature Canopy Diameters 25' - Other unitless
6 Tree Well(s) Soil Depth (Installation Depth)
Must be 30, 36, 42, or 48 Inches; Select from Standard Depths**48 inches
7 Number of Identical* Tree Wells Proposed for this DMA 1 trees
8 Proposed Width of Tree Well(s) Soil Installation for One (1) Tree 14.0 feet
9 Proposed Length of Tree Well(s) Soil Installation for One (1) Tree 18.0 feet
10 Botanical Name of Tree Species Provide in PDP SWQMP --------- unitless
11 Tree Species Mature Height per SD-A Provide in PDP SWQMP --------- feet
12 Tree Species Mature Canopy Diameter per SD-A 25 --------- feet
13 Minimum Soil Volume Required In Tree Well
(2 Cubic Feet Per Square Foot of Mature Tree Canopy Projection Area)982 --------- cubic-feet
14 Credit Volume Per Tree 290 --------- cubic-feet
15 DCV Multiplier To Meet Flow Control Requirements n/a --------- unitless
16 Required Retention Volume (RRV) To Meet Flow Control Requirements n/a --------- cubic-feet
17 Number of Trees Required 1 --------- trees
18 Total Area of Tree Well Soil Required for Each Tree 245 --------- sq-ft
19 Approximate Required Width of Tree Well Soil Area for Each Tree 16 --------- feet
20 Approximate Required Length of Tree Well Soil Area for Each Tree 16 --------- feet
21 Number of Trees Proposed for this DMA 1 --------- trees
22 Total Area of Tree Well Soil Proposed for Each Tree 252 --------- sq-ft
23 Minimum Spacing Between Multiple Trees To Meet Soil Area Requirements
(when applicable)***n/a --------- feet
24 Are Tree Well Soil Installation Requirements Met?Yes Incomplete -Incomplete Incomplete Incomplete Incomplete Incomplete -- yes/no
25 Is Remaining DCV Requirement Fully Satisfied by Tree Well(s)?Yes Incomplete -Incomplete Incomplete Incomplete Incomplete Incomplete -- yes/no
26 Is Hydromodification Control Requirement Satisfied by Tree Well(s)?n/a n/a -n/a n/a n/a n/a n/a --yes/no
Notes:
*If using more than one mature canopy diameter within the same DMA, only the smallest mature canopy diameter should be entered. Alternatively, if more than one mature canopy diameter is proposed and/or the dimensions of multiple tree well installations will vary, separate DMAs may be delineated.
**If the actual proposed installation depth is not available in the table of standard depths, select the next lower depth.
***Tree Canopy or Agency Requirements May Also Influence the Minimum Spacing of Trees.
Standard Tree
Well Inputs
Attention!
Tree Data
Tree Well Sizing
Calculations
Results
False
False
False
False
SSD-BMP Automated Worksheet I-3: Step 3. Tree Well Sizing (V1.0)
False
-[Line 12] Applicant to provide supporting documentation for tree species in PDP SWQMP.
OFF-SITE
TREE WELL 1 (EXCESS AREA, DMA-3)
Area Weighted Runoff Factor (C )
Surface Type Area - A (sf) C - Factor C X A
Weighted C-
Factor
Impervious 5,916 0.90 5,324
Landscape 589 0.10 59
Gravel/DG 0 0.30 0
Total 6,505 5,383 0.828
0.15 Acres
County of San Diego BMP Design Manual (2020)
C 0.828
I (in/hr)0.2
A (Ac)0.15
Q (cfs)0.025
Project: Front Porch
B.4.5 Offline BMPs
Diversion flow rates for of£line Bi'v[Ps must be sized to convey the maximum flow rate of runoff
produced from a rainfalJ intensity of 0.2 inch of rainfa!J per hour, for each hour of every storm event.
The following hyd rologic method must be used to calculate the di-version flow rate for off-line BMPs:
Q =CxixA
Where:
Q = Diversion flow rate in cubic feet per second
C = Runoff factor, area weighted estimate using Table B.1-l
i = Rainfall intensity of 0.2 in/hr
A= Tributary area (acres)
Inlet Report
Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc.Friday, Dec 29 2023
Curb Inlet to Tree Well #1
Curb Inlet
Location = On grade
Curb Length (ft) = 3.00
Throat Height (in) = 4.00
Grate Area (sqft) = -0-
Grate Width (ft) = -0-
Grate Length (ft) = -0-
Gutter
Slope, Sw (ft/ft) = 0.001
Slope, Sx (ft/ft) = 0.015
Local Depr (in) = 2.00
Gutter Width (ft) = 1.00
Gutter Slope (%) = 8.09
Gutter n-value = 0.016
Calculations
Compute by:Known Q
Q (cfs)= 0.03
Highlighted
Q Total (cfs)= 0.03
Q Capt (cfs)= 0.03
Q Bypass (cfs) = -0-
Depth at Inlet (in) = 2.18
Efficiency (%)= 100
Gutter Spread (ft) = 1.93
Gutter Vel (ft/s) = 1.44
Bypass Spread (ft) = -0-
Bypass Depth (in) = -0-
All dimensions in feet
GS-1.02
LARGE TREE
WELL
PLAN VIEW
SECTION B-B
SECTION A-ANOTES:
DRAWING NOT TO SCALE
BACK OF
EX. SIDEWALK
ADHERE LINER
TO LIMITS OF
REPLACED
SIDEWALK
CURB & GUTTER
PER SDRSD G-02
R/W
#4x8" SMOOTH
DOWELS @ 18" O.C,
GREASED ON ONE END,
TYP. ALL SIDES
REPLACE SIDEWALK
AS NECESSARY
FOR EXPANDED
STRUCTURAL SOIL
VOLUME
7'-0"
1. REFER TO GS-1.00 FOR ALL DETAILS NOT SHOWN HERE.
2. TREE SIZE & TYPE PER DESIGN PLANS.
30 MIL
PLASTIC
LINER
LIMITS OF ROOTING SOIL
PER DESIGN PLANS
REPLACE SIDEWALK AS
NECESSARY FOR EXPANDE
STRUCTURAL SOIL VOLUME
EEP ROOT
TREE BUBBLER
ER~04
OOT CONT OL
BARRIER PER
SDRSD L-06
30 MIL
PLASTIC
LINER
EXPANSION JOINT,
TYP. ALL SIDES
INSTALL 30 MIL PLASTIC
LINER WHERE CONCRETE IS
POURED OVER STRUCTURAL
SOIL (TYP.)
30 MIL
PLASTIC
LINER
SAN DIEGO COUNTY DESIGN STANDARD REVISIONS APPROVED DATE
RECOMMENDED BY CHARLES MOHRLOCK, P.E. t-------------------------l---O_R_IG_I_NA_L----1-__ ___J_:_10-=---=0:_:_1-_:2:_::_0_:_::__i19
DRAWN BY ADB CHECKED BY: _fil'_
APPROVED BY COUNTY ENGINEER
~() 'W\tl'l~DATE: to/1<+./t"I
WILLIAM P. MORGAti,P.E.
R.C.E. NO. 49452, EXP 9/30/2020
DRAWING
NUMBER
GS-1.03
PLAN VIEW
SECTION C-C
SECTION B-B
NOTES:
DRAWING NOT TO SCALE
30 MIL
PLASTIC
LINER DEEP ROOT
TREE BUBBLER
PER SDRSD 1-04
ADHERE LINER
TO LIMITS OF
REPLACED
SIDEWALK
A
EXPANSION JOINTS,
TYP. ALL 3 SIDES
CURB & GUTTER
PER SDRSD G-02
#4x8" SMOOTH
DOWELS @ 18" O.C,
GREASED ON ONE END ,
TYP. ALL 3 SIDES
5' MIN. _J• ---------
11. ·. • .. • ' • • ·•2:0% '. ,• • •:• .' .• • • r
1. REFER TO GS-1.OO FOR ALL DETAILS NOT SHOWN HERE.
2. TREE SIZE & TYPE PER DESIGN PLANS.
SIDEWALK UNDERDRAIN
PER GS-5.O4
TYPE PER DESIGN PLANS
EXPANSION JOINTS,
TYP. ALL 3 SIDES
SPLASH PAD
PER GS-5.O6
DRAWN BY ADB CHECKED BY: _fil'_ SAN DIEGO COUNTY DESIGN STANDARD
#4x8" SMOOTH
DOWELS @ 18" O.C,
GREASED ON ONE END,
TYP. ALL 3 SIDES
LIMITS OF ROOTING SOIL
PER DESIGN PLANS
REPLACE SIDEWALK AS
NECESSARY FOR EXPANDED
STRUCTURAL SOIL VOLUME
A
30 MIL
PLASTIC
LINER
R/W
I
MATCH EX.
GROUND
ELE VATION
30 MIL
PLASTIC
LINER
#4 @ 18" O.C.
BOTH WAYS
ROOT CONTROL
BARRIER PER
SDRSD L-06
SAND FILTER
LAYER
REVISIONS APPROVED DATE
RECOMMENDED BY CHARLES MOHRLOCK, P.E.1-----------------------t----1 -1 ---1 ORIGINAL 10-01-2019
APPROVED BY COUNTY ENGINEER
~() 'W\tll~DATE: to/1<+./t"I
WILLIAM P. MORGAti,P.E.
R.C.E. NO. 49452, EXP 9/30/2020
TREE WELL ADJACENT
TO RIGHT-OF-WAY DRAWING
NUMBER
GS-5.04a
PLAN
SECTION A-A
SECTION B-B
NOTES:ANCHOR DETAIL
DRAWING NOT TO SCALE
CONSTRUCTION
JOINT
A 4" RADIUS, L I TYP
ANCHOR
MONOLITHIC_,,)
GUTTER
I CURB LINE
CONSTRUCTION
JOINT
2-fx2"x¾"X4'
GALVANIZED STEEL
ANGLE FACE PLATE
/
1" TO 4"
GUTTER DEPRESSION
(PER PLANS)
' 0::: L{) _J • ----+
,..: 0 • 16"1 .18"~36". k·I.
SEE NOTE 4
1. CONCRETE SHALL BE 560-C-3250.
CURB & FL
ELEVS. PER PLANS
(TYP.)
#4 @ 6" O.C.
co BOTH WAYS
CONTINUOUS
NOTE:
THIS TYPE OF DESIGN CAN CONNECT TO
& ACCOMMODATE ANY TYPE OF BMP.
A
_J
PER PLANS, 10'-0" MAX.
PER PLANS, 10'-0" MAX.
#4 @ 6" O.C.
BOTH WAYS
CONTINUOUS
2.0%
ELEV.
PER PLANS
(TYP.)
FREE FLOW
2. SECTION TO BE SLOPED LATERALLY WITH TOP CONFORMING TO GRADES OF THE EXISTING SIDEWALK & CURB.
3. TROWEL FINISH TOP SURFACE & FLOOR OUTELT. REPRODUCE MARKINGS OF EXISTING SIDEWALK AND CURB.
4. OPENING WIDTHS IN EXCESS OF 3-FT (TO CON VEY THE 10-YR STORM EVENT) SHALL REQUIRE APPROVED
STRUCTURAL CALCULATIONS.
5. GUTTER TRANSITION LENGTH PER DESIGN PLANS; AN ADDITIONAL 2.5-FT CURB TRANSITION LENGTH IS
RECOMMENDED FOR EVERY 1" OF ADDITIONAL GUTTER DEPRESSION.
6. ELEVATIONS SHALL BE SHOWN ON PLANS WHERE INDICATED BY "0" SYMBOL.
DRAWN BY __AOO_ CHECKED BY: _fil'_ REVISIONS APPROVED DA TE SAN DIEGO COUNTY DESIGN STANDARD
RECOMMENDED BY CHARLES MOHRLOCK, P.E. 1------------------------+-0_R_IG_IN_A_L--+---+-10_-_0_1-_2_01----l9
APPROVED BY COUNTY ENGINEER
~() 1'\l\tll~DATE: to/1<+./t"I
WILLIAM P. MORGAti,P.E.
R.C.E. NO. 49452, EXP 9/30/2020
SIDEWALK
UNDERDRAIN DRAWING
NUMBER
SD-A Tree Well
SD-A Tree Well
MS4 Permit Category
Site Design
Retention
Manual Category
Site Design
Infiltration
Applicable Performance
Standard
Site Design
Pollutant Control
Flow Control
Primary Benefits
Volume Reduction
(Source: County of San Diego LID Manual – EOA, Inc.)
Trees planted to intercept rainfall and runoff as described in this fact sheet may be used as storm water
management measures to provide runoff reduction of the DCV per Appendix B.1.4. Additional
benefits associated with tree wells, include energy conservation, air quality improvement, and aesthetic
enhancement. Tree wells located in the City’s Right-of-Way are subject to the discretion of City
Engineer and Parks and Recreation Director. Typical storm water management benefits associated
with trees include:
• Treatment of storm water – Storm water from impervious area should be directed to the
tree wells. Trees provide treatment through uptake of nutrients and other storm water
pollutants (phytoremediation) and support of other biological processes that break down
pollutants
• Interception of rainfall – tree surfaces (roots, foliage, bark, and branches) intercept,
evaporate, store, or convey precipitation to the soil before it reaches surrounding impervious
surfaces
• Reduced erosion – trees protect denuded area by intercepting or reducing the velocity of rain
drops as they fall through the tree canopy
• Increased infiltration – soil conditions created by roots and fallen leaves promote infiltration
E-3 Jan. 2023
SD-A Tree Well
Typical tree well system components include:
• Directing runoff from
impervious areas through a
drainage opening into a tree well
planting area.
• Trees of the appropriate species
for site conditions and
constraints. Refer to the Plant
List fact sheet (Appendix E.21).
• Available soil media reservoir
volume based on mature tree size,
soil type, water availability,
surrounding land uses, and
project goals
• Optional suspended pavement
design to provide structural
support for adjacent pavement
without requiring compaction of underlying layers
Schematic of Tree Well
• Optional root barrier devices as needed; a root barrier is a device installed in the ground,
between a tree and the sidewalk or other structures, intended to guide roots down and away
from the sidewalk or structures in order to prevent damage from tree roots.
• Optional tree grates; to be considered to maximize available space for pedestrian circulation
and to protect tree roots from compaction related to pedestrian circulation; tree grates are
typically made up of porous material that will allow the runoff to soak through.
• Optional shallow surface depression for ponding of excess runoff
• Optional planter box underdrain
Site design BMP to provide incidental treatment. Tree wells primarily functions as site design
BMPs for incidental treatment.
Storm water pollutant control BMP to provide treatment. Project proponents are allowed to
design tree wells to reduce the volume of stormwater runoff that requires treatment, (the Design
Capture Volume [DCV]), or completely fulfill the pollutant control BMP requirements by retaining
the entire DCV. Benefits from tree wells are accounted for by using the volume reduction values in
Table B.1-3 presented in Appendix B. This credit can apply to other trees that are used for landscaping
purposes that meet the same criteria. Project proponents are required to provide calculations
supporting the amount of credit claimed from implementing trees within the project footprint. Tree
wells designed to completely fulfill the pollutant control BMP requirements by retaining the entire
E-4 Jan. 2023
Design Adaptations for Project Goals
RUNOFF ~
PAVEMENT
SECTION 00000000000
,.. ........ 0 0 ooo
V • • NATIVE SOIL
y'l'VV'i/V 'l''t''i''tl
'I' 'I' '¥ ,;, V '+' 'I' '¥ '+'
\i 'I' V 'V V 'I' 'I' 'i'
• • , OPTIONAL
BARRIER
000000000000000 0 0 O O O 0
000000000000000
00000 ooo ooo
0000 00000
o o o o o o o TREE WELL SOIL o o o o o o o o o o
0 0 O
000000000000000
o o o o o o o o o o OPTIONAL o o
o o o O o o o o o o o o o o o o o o o o 0 UNDERDRAIN o o
0000000000
0 ooo ooo
0 0 0 0 0
SD-A Tree Well
DCV are designated as SSD-BMPs and located in Appendix I.
Flow Control BMP to meet hydromodification requirements. Project proponents are also allowed
to design tree wells as a flow control BMP. Benefits from tree wells are accounted for by using the
DCV multipliers listed in Appendix I. Project proponents are required to provide calculations showing
that the entire DCV including the DCV multiplier is retained.
Tree Wells, whether designed as Site Design BMPs, as Stormwater Pollutant Control BMP, or as a
Flow Control BMP must meet the following design criteria and considerations, and if placed in the
right-of-way must be consistent with the County of San Diego Green Streets Standard Drawings.
Deviations from the below criteria may be approved at the discretion of the City Engineer if it is
determined to be appropriate:
Siting and Design Intent/Rationale
Tree species is appropriately chosen for the
development (private or public). For public
rights-of-ways, city planning guidelines and
□ zoning provisions for the permissible species
and placement of trees are consulted. A list of
trees appropriate for site design are provided in
Appendix E.21
Tree well placement: ensure area is graded;
□ and the well is located so that full amount of
DCV reduction drains to well.
Location of trees planted along public streets
follows city requirements and guidelines.
Vehicle and pedestrian line of sight are
considered in tree selection and placement.
Location of trees planted within private
development follows city landscape guidelines.
Building setbacks, utility alignments, vehicle
and pedestrian line of sight are considered in
tree selection and placement.
Unless otherwise approved by the City
Engineer the following minimum tree
separation distance is followed
Proper tree placement and species
selection minimizes problems such as
pavement damage by surface roots and
poor growth.
Minimizes short-circuiting of run off and
assures DCV reductions are retained
onsite.
Roadway safety for both vehicular and
pedestrian traffic is a key consideration
for placement along public streets.
E-5 Jan. 2023
Design Criteria and Considerations
□
SD-A Tree Well
Siting and Design Intent/Rationale
Improvement
Minimum
distance to
Tree Well
Traffic Signal, Stop sign 20 feet
Underground Utility lines
(except sewer) 5 feet
Sewer Lines 10 feet
Above ground utility
structures (Transformers,
Hydrants, Utility poles, etc.)
10 feet
Driveways 10 feet
Intersections (intersecting
curb lines of two streets) 25 feet
Underground utilities and overhead wires
are considered in the design and avoided or
circumvented. Underground utilities are routed
□ around or through the planter in suspended
pavement applications. All underground
utilities are protected from water and root
penetration.
Suspended pavement is used for confined
Tree Well soil volume. Suspended pavement
design was developed where appropriate to
□ minimize soil compaction and improve infiltration and filtration capabilities.
Suspended pavement was constructed with an
approved structural cell.
A minimum soil volume of 2 cubic feet per
square foot of canopy projection volume is
provided for each tree. Canopy projection area
Tree growth can damage utilities and
overhead wires resulting in service
interruptions. Protecting utilities routed
through the planter prevents damage and
service interruptions.
Suspended pavement designs provide
structural support without compaction
of the underlying layers, thereby
promoting tree growth.
Recommended structural cells include
poured in place concrete columns, Silva
Cells manufactured by Deeproot Green
Infrastructures and Stratacell and
Stratavault systems manufactured by
Citygreen Systems or approved equal.
Suspended pavement shall not be used
within the city’s right-of-way and
easements.
The minimum soil volume ensures that
there is adequate storage volume to
allow for unrestricted evapotranspiration
and infiltration.
E-6 Jan. 2023
□
Siting and Design Intent/Rationale
is the ground area beneath the tree, measured at
the drip line. Soil volume must be within 1.5
times the mature tree canopy radius. Soil depth
shall be a minimum of 30 inches deep,
preferably 36 inches deep. When placing tree
well next to curbs or other structures use
Structural Soil as outlined in the section below
titled “Confined Tree Well Soil Volume”. Use
Amended Soil per Fact Sheet SD-F in all other
cases.
SD-A Tree Well
DCV from the tributary area draining to the
□ tree is equal to or greater than the tree credit
volume
Inlet opening to the tree that is at least 18
inches wide.
A minimum 2 inch drop in grade from the inlet
□ to the finish grade of the tree.
Grated inlets are allowed for pedestrian
circulation. Grates need to be ADA compliant
and have sufficient slip resistance.
The minimum tributary area ensures that
the tree receives enough runoff to fully
utilize the infiltration and
evapotranspiration potential provided. In
cases where the minimum tributary area
is not provided, the tree credit volume
must be reduced proportionately to the
actual tributary area.
Design requirement to ensure that the
runoff from the tributary area is not
bypassed.
Different inlet openings and drops in
grade may be allowed at the discretion of
the City Engineer if calculations are
shown that the diversion flow rate
(Appendix B.4.4) from the tributary area
can be conveyed to the tree. In cases
where the inlet capacity is limiting the
amount of runoff draining to the tree,
the tree credit volume must be reduced
proportionately.
Determine the areas where tree wells can be used in the site design to achieve incidental treatment.
Tree wells reduce runoff volumes from the site. Refer to Appendix B.1. Document the proposed tree
locations in the SWQMP.
For conceptual design and sizing approach for pollutant control and flow control, refer to Appendix
I.
E-7 Jan. 2023
Conceptual Design and Sizing Approach for Site Design
-
-
SD-A Tree Well
1. Maximized open soil area for tree planting is the most cost effective method of achieving
the required soil volume.
2. Tree wells within sidewalks shall have a minimum open area of four feet wide by six feet
long. Larger areas may be required to accommodate large root balls.
3. Tree well soil characteristics shall meet the requirements of SD-F Amended Soil.
In order to provide adequate soil volume for tree wells, soils may be placed confined beneath adjacent
paved surfaces. Acceptable soil systems capable of carrying D-50 loading include structural soils,
structural slabs, and structural cells:
1. Structural soil systems include CU-StructuralSoilTM, Stalite Structural Soil, or equivalent.
2. Suspended pavements that allow uncompacted growing soil beneath the sidewalk include;
structural slabs that span between structural supports, structural cells, and other
commercially available structural systems. Manufacturer details and certification must be
provided for commercial systems. Structural calculations and details must be provided for
structural slab installations. Structural cells are commercially-available structural systems
placed subsurface that support the sidewalk and are filled with amended soil (SD-F).
Manufacturer details and certification must be provided for commercial systems.
Suspended pavement shall not be used within the city’s right-of-way and easements.
Tree wells with expanded soil volume will serve as a method of capturing and retaining the required
volume of stormwater in accordance with City requirements in Appendix B of this manual. These
facilities can be designed to meet the City requirements when surface ponding volume is provided,
whether designed as an enclosed plant bed with covered soil volume, or a continuous open area (either
mulched or with turf) with soil volume under the adjacent sidewalk.
Normal Expected Maintenance. Tree health shall be maintained as part of normal landscape
maintenance. Additionally, ensure that storm water runoff can be conveyed into the tree well as
designed. That is, the opening that allows storm water runoff to flow into the tree well (e.g., a curb
opening, tree grate, or surface depression) shall not be blocked, filled, re-graded, or otherwise changed
in a manner that prevents storm water from draining into the tree well. A summary table of standard
inspection and maintenance indicators is provided within this Fact Sheet.
Non-Standard Maintenance or BMP Failure. Trees wells are site design BMPs that normally do
not require maintenance actions beyond routine landscape maintenance. The normal expected
E-8 Jan. 2023
Tree Planting Design in New or Reconstructed Streetscapes
Structural Requirements for Confined Tree Well Soil Volume
Stormwater Retention and Treatment Volume
Maintenance Overview
SD-A Tree Well
maintenance described above ensures the BMP functionality. If changes have been made to the tree
well entrance / opening such that runoff is prevented from draining into the tree well (e.g., a curb
inlet opening is blocked by debris or a grate is clogged causing runoff to flow around instead of into
the tree well, or a surface depression has been filled so runoff flows away from the tree well), the BMP
is not performing as intended to protect downstream waterways from pollution and/or erosion.
Corrective maintenance will be required to restore drainage into the tree well as designed.
Surface ponding of runoff directed into tree wells is expected to infiltrate/evapotranspire within 24-
96 hours following a storm event. Surface ponding longer than approximately 24 hours following a
storm event may be detrimental to vegetation health, and surface ponding longer than approximately
96 hours following a storm event poses a risk of vector (mosquito) breeding. Poor drainage can result
from clogging or compaction of the soils surrounding the tree. Loosen or replace the soils to restore
drainage.
Other Special Considerations. Site design BMPs, such as tree wells, installed within a new
development or redevelopment project are components of an overall storm water management
strategy for the project. The presence of site design BMPs within a project is usually a factor in the
determination of the amount of runoff to be managed with structural BMPs (i.e., the amount of runoff
expected to reach downstream retention or biofiltration basins that process storm water runoff from
the project as a whole). When site design BMPs are not maintained or are removed, this can lead to
clogging or failure of downstream structural BMPs due to greater delivery of runoff and pollutants
than intended for the structural BMP. Therefore, the City Engineer may require confirmation of
maintenance of site design BMPs as part of their structural BMP maintenance documentation
requirements. Site design BMPs that have been installed as part of the project should not be removed,
nor should they be bypassed by re-routing roof drains or re-grading surfaces within the project. If
changes are necessary, consult the City Engineer to determine requirements.
E-9 Jan. 2023
SD-A Tree Well
The property owner is responsible to ensure inspection, operation and maintenance of permanent BMPs on their property unless
responsibility has been formally transferred to an agency, community facilities district, homeowners association, property owners association,
or other special district.
Maintenance frequencies listed in this table are average/typical frequencies. Actual maintenance needs are site-specific, and maintenance may
be required more frequently. Maintenance must be performed whenever needed, based on maintenance indicators presented in this table.
The BMP owner is responsible for conducting regular inspections to see when maintenance is needed based on the maintenance indicators.
During the first year of operation of a structural BMP, inspection is recommended at least once prior to August 31 and then monthly from
September through May. Inspection during a storm event is also recommended. After the initial period of frequent inspections, the minimum
inspection and maintenance frequency can be determined based on the results of the first year inspections.
Threshold/Indicator Maintenance Action Typical Maintenance Frequency
Tree health Routine actions as necessary to maintain
tree health.
• Inspect monthly.
• Maintain when needed.
Dead or diseased tree Remove dead or diseased tree. Replace per
original plans.
• Inspect monthly.
• Maintain when needed.
Standing water in tree well for longer than
24 hours following a storm event
Surface ponding longer than approximately
24 hours following a storm event may be
detrimental to tree health
Loosen or replace soils surrounding the
tree to restore drainage.
• Inspect monthly and after every 0.5-inch
or larger storm event. If standing water is
observed, increase inspection frequency
to after every 0.1-inch or larger storm
event.
• Maintain when needed.
Presence of mosquitos/larvae
For images of egg rafts, larva, pupa, and
adult mosquitos, see
http://www.mosquito.org/biology
Disperse any standing water from the tree
well to nearby landscaping. Loosen or
replace soils surrounding the tree to restore
drainage (and prevent standing water).
• Inspect monthly and after every 0.5-inch
or larger storm event. If mosquitos are
observed, increase inspection frequency
to after every 0.1-inch or larger storm
event.
• Maintain when needed
E-10 Jan. 2023
Summary of Standard Inspection and Maintenance
SD-A Tree Well
Threshold/Indicator Maintenance Action Typical Maintenance Frequency
Entrance / opening to the tree well is
blocked such that storm water will not drain
into the tree well (e.g., a curb inlet opening
is blocked by debris or a grate is clogged
causing runoff to flow around instead of
into the tree well; or a surface depression is
filled such that runoff drains away from the
tree well)
Make repairs as appropriate to restore
drainage into the tree well.
• Inspect monthly.
• Maintain when needed.
E-11 Jan. 2023
ATTACHMENT 2
BACKUP FOR PDP HYDROMODIFICATION CONTROL MEASURES
[This is the cover sheet for Attachment 2.]
Indicate which Items are Included behind this cover sheet:
Attachment
Sequence
Contents Checklist
Attachment 2a Hydromodification Management
Exhibit (Required)
Not applicable.
Site is exempt for hydromodification.
See Hydromodification Management
Exhibit Checklist on the back of this
Attachment cover sheet.
Attachment 2b Management of Critical Coarse
Sediment Yield Areas (WMAA
Exhibit is required, additional
analyses are optional)
See Section 6.2 of the BMP Design
Manual.
Not applicable.
Exhibit showing project drainage
boundaries marked on WMAA
Critical Coarse Sediment Yield
Area Map (Required)
Optional analyses for Critical
Coarse Sediment Yield Area
Determination
Appendix H.6.1 Verification of
Geomorphic Landscape Units
Onsite
Appendix H.7 Downstream
Systems Sensitivity to Coarse
Sediment
Attachment 2c Geomorphic Assessment of
Receiving Channels (Optional)
See Section 6.3.4 of the BMP Design
Manual.
Not performed
Attachment 2d Flow Control Facility Design and
Structural BMP Drawdown
Calculations (Required)
See Chapter 6 and Appendix G of the
BMP Design Manual
Not applicable
HMP EXEMPT PER SAN DIEGO COUNTY REGIONAL WMAA MAP
Use this checklist to ensure the required information has been included on the
Hydromodification Management Exhibit:
The Hydromodification Management Exhibit must identify:
Underlying hydrologic soil group
Approximate depth to groundwater
Existing natural hydrologic features (watercourses, seeps, springs, wetlands)
Critical coarse sediment yield areas to be protected (if present)
Existing topography
Existing and proposed site drainage network and connections to drainage offsite
Proposed grading
Proposed impervious features
Proposed design features and surface treatments used to minimize imperviousness
Point(s) of Compliance (POC) for Hydromodification Management
Existing and proposed drainage boundary and drainage area to each POC (when necessary,
create separate exhibits for pre-development and post-project conditions)
Structural BMPs for hydromodification management (identify location, type of BMP, and
size/detail)
HMP EXEMPT PER SAN DIEGO COUNTY
REGIONAL WMAA MAP
HMP EXEMPT EXHIBIT
Project Site
110
CARLSBADCARLSBAD
DELDELMARMAR
ENCINITASENCINITAS
ESCONDIDOESCONDIDO
OCEANSIDEOCEANSIDE
POWAYPOWAY
S.D.S.D.COUNTYCOUNTY
S.D.S.D.COUNTYCOUNTY
S.D.S.D.COUNTYCOUNTY
SANSANDIEGODIEGO
SANSANMARCOSMARCOS
VISTAVISTA
S a n Marcos Cr e e k
S a n t a M a r g a rita
River
Sa nMarcos C r e e k
E s c o n d i d o C r e e k
Ra t t l esnakeCree k
Agua He dio n d a Creek
S a n L u i s R e yRiver
B u e n a Vist a
C
r e e k
Lusardi Creek
E
n
cinitas C re e k
S a nt a Y sa b e l C r eek
S a nDieguit o Rive r
S an Diegu it oRiver
Receiving Waters and Conveyance Systems Exemptfrom Hydromodification Management Requirements Exhibit Date: Sept. 8, 2014
Aerial Imagery Source: DigitalGlobe, 06/2012
NORTH
Key Map (Not to Scale)
Legend
Municipal Boundaries
Water Storage Reservoirs, Lakes,Enclosed Embayments, PacificOcean, Buena Vista Lagoon
Reaches of San Luis Rey River, SanDieguito River, San Diego River,Forester Creek, Sweetwater River,Otay River
0 5 102.5 Miles
Watershed Boundaries
Regional WMAA Streams
Exempt River Reaches:
Existing underground storm drains orconveyance channels whose bedand bank are concrete-lined,discharging directly to exempt waterbodies, exempt rivers, or localizedareas of Agua Hedionda Lagoon andBatiquitos Lagoon
Exempt Conveyance Systems:
Exempt Bodies:
Carlsbad Watershed Management AreaHU 904.00, 211 mi2
Site
Location
J I I I ' I
/ j
i,
i i ,-----i i ----'
I
Geosyntec t>
consultants
SA N .Jj,,CIN r o M M:J,;rAINS ' ~
C ah1,11la
ln.d,an
FLuar,,at,an
.I r
An:ra-l!c,r"IUQ
"'''" Sia» P•l ~
' Oco•~Dlll't .. .-w, .. ~rar -1-•
-,
'
s.,1t
Cil
,.11.1 m
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.
RICK a
ENGINEERING COMPANY
ATTACHMENT 3
Structural BMP Maintenance Information
Use this checklist to ensure the required information has been included in the Structural
BMP Maintenance Information Attachment:
Preliminary Design/Planning/CEQA level submittal:
Attachment 3 must identify:
Typical maintenance indicators and actions for proposed structural BMP(s) based
on Section 7.7 of the BMP Design Manual
Final Design level submittal:
Attachment 3 must identify:
Specific maintenance indicators and actions for proposed structural BMP(s). This
shall be based on Section 7.7 of the BMP Design Manual and enhanced to reflect
actual proposed components of the structural BMP(s)
How to access the structural BMP(s) to inspect and perform maintenance
Features that are provided to facilitate inspection (e.g., observation ports, cleanouts,
silt posts, or other features that allow the inspector to view necessary components
of the structural BMP and compare to maintenance thresholds)
Manufacturer and part number for proprietary parts of structural BMP(s) when
applicable
Maintenance thresholds for BMPs subject to siltation or heavy trash(e.g., silt level
posts or other markings shall be included in all BMP components that will trap and
store sediment, trash, and/or debris, so that the inspector may determine how full
the BMP is, and the maintenance personnel may determine where the bottom of
the BMP is . If required, posts or other markings shall be indicated and described
on structural BMP plans.)
Recommended equipment to perform maintenance
When applicable, necessary special training or certification requirements for
inspection and maintenance personnel such as confined space entry or hazardous
waste management
ATTACHMENT 4
City standard Single Sheet BMP (SSBMP) Exhibit
[Use the City’s standard Single Sheet BMP Plan.]
SD SD SDSDSDSD
SD
SD
SD
SD
SD
SD
SD
SD
SD SD SD SD SD
S
D
SD
SD SD SD SD SD SD SD
SD
SD
SD
SD
SD
SD
S
D
S S S S S S S S S S S S S S S
S S S S S S S S S S S S S S S
W W W W W W W W W W W W W WW
W
W
W
W
W
W
W
W
W
W
WWWW
SS S
OHE
OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE
OHE
OHE
S
W
W
W
W
W
W
W
W
W
FW
FW
S S
IRRG IRRG IRRG IRRG IRRG IRRG IRRG IRRG
FF 51.75
FF 42.50FF 51.75
FF 42.50
A-5A-5
10
.
0
0
'
10
.
0
0
'
W
W
EC
51
51
51
50
34
35
36
37
38
39
40
41
42
43
9449 BALBOA AVE, STE 270
SAN DIEGO, CA 92123 619.299.5550BWE JOB NO. 13913US1.00
SD
ENGINEERING DEPARTMENT
2710, 2720, 2730, & 2740 OCEAN STREET
CARLSBAD, CA. 92008
SITE DESIGN BMPS:
SOURCE CONTROL BMPS:
LEVEL 1
GARAGE
PERMEABLE PAVEMENT & LINER DETAILNOT TO SCALE
MATCHLINE SHEET 2
MA
T
C
H
L
I
N
E
S
H
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T
2
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c:
Q_
z z
< ~ :::.
°" °" ~ ..,
!;;;
3:: 3::
\
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Iii u <
':.i-' <O
OMA Unique Identifier
A-1
A-2
A-3
A-4
A-5
A-6
A-7
B-1
B-2
B-3
B-4
TOTAL
OFF-1
OFF-2
OFF-3
OFF-4
TOTAL OFFSI TE
i
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EXT PAGE
ROOF
LINE
TYP
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---
::===t 47
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■
E-MINIMIS
DMA
, ___ ,...;. .. ,-_
Tabular Summary of DMAs
/9960F~
/ - -J
46
I
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DRi\lEWAY
.......__'
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DRAINS
BMP #1
rt
10300FS
PER 347~2 iJRI\IEW.
, ..... ,_
SC-A
SC-B
---------.. _ -----------------------------------
I I
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VARIES
I 100.00FS
~
I A-1 ■
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BASEMENT
CD-_...,___,___ - - --a
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®--------0-------,-
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Worksheet B-1
--I ~·+
A-4
·-. CotlC
!SD-B !
·.--·""'!"'·'-· --· -•·""'!"' ~...,__~ -, r PRIVAlE
'{ _-BACKYARD I
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--------------
-----®
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SUMP PUMP #1: ~·+
I<
+
DRAINS TO
BMP fl
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Area (acres) Impervious Ar ea (acres} %Imp HSG Area Weighted Runoff Coefficient (C) DCV (cubic feet) Mitigated By (BM PI D) Pollutant Control Type Drainsto(POCID)
0.053 0.052 99.3% B 0.894 103 BMP#3 BF-3 Proprietary Biofiltration 1
0.082 0.074 90.2% B 0.822 150 4 BF-3 Proprietary Biofiltration 1
0.034 0.024 70.6% B 0.665 49
0.136 0.136 99.7% B 0.898 267 BMP#2
0.083 0.074 89.2% B 0.813 148 BM P# 1
0.049 0.049 100.0% B 0.900 96 BMP#5
0.130 0.082 63.1% B 0.605 175 BMP#5
0.010 0.008 82.2% B 0.757 17 TreeWell#2
0.005 0.005 100.0% B 0.900 De-minimis
0.019 0.014 73.8% B 0.690 29 6
0.017 0.010 61.4% B 0.591 22
0.618 0.529 85.6% B 0.785 1,056
0.053 0.053 100.0% B 0.900 104
0.035 0.035 100.0% B 0.900 68
BF-3 Proprietary Biofiltration 1
BF-3 Proprietary Biofiltration 1
BF-3 Proprietary Biofiltration 1
BF-3 Proprietary Biofiltration 1
BF-3 Proprietary Biofiltration 1
Other 1
De-minim is 1
I NF-3 Pervious Pavers 1
I NF-3 Pervious Pavers 1
1
SSD-BM P Tree Wei I # 1 1
SSD-BM P Tree Wei I # 1 1 5 0 10
~-✓ ~ /,__,
B\V E
20 CIVIL •STRUCTURAL•SURVEY• PLANNING
0.023 0.010 42.0% B 0.436 22
0.033 0.014 41.9% B 0.435 31 SSD-BM P Tree Wei I # 1
SSD-BM P Tree Wei I # 1 1
1 SCALE IN FEET
1 inch = 10 ft.
DATE IN\TlAL
ENGINEER OF WORK
0.144 0.111 77.4% B 0.719 225 1
CT 2022-0003/CUP 2022-0014/CDP 2022-0047 (DEV2022-0063)
PARTY RESPONSIBI E FOR MAINTENANCE
jY ., NAME FRONT PORCH COMMUNITIES
~:£._ADDRESS BOO NORTH BRAND BLVD. CONTACT JOAN JOHNSON
191H FLOOR
BMP CONSTRUCTION AND
INSPECTION NOTES
GLENDALE, CA 92103
PHONE NO .. ~m~o _____ _
PLAN PREPARED BY:
NAME HECTOR MAYTORENA
COMPANY_,,B,,,WE..._.l...,NC..._ ___ _
ADDRESS 2449 BALBOA AVENUE
SUIJE 270
SAN DIEGO, CA 92123
PHONE NO. 619 299 5550
BMP NOTES
SIGNATURE
CERTIFlCA TION RCE 86216
1. THESE BMPS ARE MANDATORY TO BE INSTALLED PER
MANUFACTURER'S RECOMMENDATIONS OR lHESE PLANS.
lHE EOW WILL VERIFY THAT PERMANENT BMPS ARE
CONSTRUCTED AND OPERA TING IN COMPLIANCE 1'111H THE
APPLICABLE REQUIREMENTS. PRIOR TO OCCUPANCY THE EOW
MUST PROVIDE:
1. PHOTOGRAPHS OF lHE INSTALLATION OF PERMANENT
BMPS PRIOR TO CONSTRUCTION, DURING CONSTRUCTION,
AND AT FINAL INSTALLATION.
2. A WET STAMPED LETlER VERIFYING THAT PERMANENT
BMPS ARE CONSTRUCTED AND OPERATING PER lHE
REQUIREMENTS OF THE APPROVED PLANS.
3. PHOTOGRAPHS TO VERIFY lHAT PERMANENT WA lER
QUALITY TREAlMENT SIGNAGE HAS BEEN INSTALLED.
PRIOR TO RELEASE OF SECURITIES, THE DEVELOPER IS
RESPONSIBLE FOR ENSURING lHE PERMANENT BMPS HA VE NOT
BEEN REMOVED OR MODIFIED BY lHE NEW HOMEOWNER OR HOA
WllHOUT THE APPROVAL OF THE CITY ENGINEER.
LEGEND SYMBOL
EXISTING BUILI 2. NO CHANGES TO lHE PROPOSED BMPS ON lHIS SHEET
WITHOUT PRIOR APPROVAL FROM lHE CITY ENGINEER. PROPERTY LINE/RIGHT-OF-WAY
CENTER LINE
-ROW - - -P/L---C/L-----
GU Q c"
3. NO SUBSTITUTIONS TO THE MA TERI AL OR TYPES OR
PLANTING TYPES WllHOUT PRIOR APPROVAL FROM lHE CITY
ENGINEER.
4. NO OCCUPANCY WILL BE GRANTED UNTIL lHE CITY
INSPECTION STAFF HAS INSPEClED THIS PROJECT FOR
APPROPRIAlE BMP CONSTRUCTION AND INSTALLATION.
5. REFER TO MAINTENANCE AGREEMENT DOCUMENT.
6. SEE PROJECT SWMP FOR ADDlllONAL INFORMATION.
@ OVERHEAD COVERING
-MA lERIALS & EQUIPMENT STORAGE
@ SEPARATION FLOWS FROM ADJACENT AREAS
-MAlERIALS & EQUIPMENT STORAGE
STORM DRAINS AND CATCH BASINS
1'11LL BE LABELED 1'11TH STENCILING
OR SIGNAGE TO DISCOURAGE
DUMPING
! SD-B ! DIRECT RUNOFF TO PERVIOUS AREAS
-SIDEWALKS & WALKWAYS
-DRII/EWA YS
-PATIOS, DECKS, & COURTYARDS
-ROOFTOP AREAS
! SD-I ! CONSTRUCT SURFACES FROM PERMEABLE MATERIALS
-PARKING AREAS & WALKWAYS
-PATIOS, DECKS, & COURTYARDS
! SD-K ! SUSTAINABLE LANDSCAPING
STRUCllJRAL BMP KEYNOTES
VCOMPACT PROPRIETARY BIOFILTRATION BMP (POLLUTANT CONTROL)
~PERMEABLE PAVEMENT BMP (POLLUTANT CONTROL)
SWOMP NOTES
1. lHE SITE IS COMPRISED OF HYDROLOGIC
SOIL TYPE B.
2. APPROXIMATE DEPlH TO GROUNDWATER
GREA lER THAN 30 FEET
EXISTING NA TUR AL HYDROLOGIC FEATURES
-NOT APPLICABLE
NO CRlllCAL COARSE SEDIMENT YIELD
AREAS ARE NOT PRESENT ON SITE
PROJECT DISCHARGES DIRECll Y INTO
HARDENED CONVEYANCE AND ROUlED
DIRECll Y TO THE PACIFIC OCEAN.
PROJECT IS HYDROMODIFICA TION EXEMPT.
NOTES:
PROPOSED
BUILDING/
STRUCTURE
SUBGRADE
AC PAVEMENT
AC PAVEMENT GRIND & OVERLAY
CONCRElE PAVEMENT
PAYERS
NEW CATCH BASIN SIZE PER PLAN
NEW AREA DRAIN
NEW ROOF DRAIN PER PLUMBING PLAN
NEW SEWER/STORM DRAIN CLEANOUT
SllE WALL I I I I I I I I I
STORM DRAIN
MODULAR WETLAND
12" TRENCH DRAIN
STORM DRAIN CLEANOUT TYPE A4
STREET TREE BOX
SUMP PUMP
ROOF DRAIN DAYLIGHTS TO
BMP PER PLUMBING PLANS
□
[Q]
PERMEABLE PA VERS 11 I I I I I I ~
PROJECT OUlER DMA BOUNDARY
DMA BOUNDARY
EXISTING CONTOUR
NEW CONTOUR
FLOW DIRECTION
FLOW PATH
POINT OF COMPLIANCE (POC)
DRAINAGE MANAGEMENT AREA MARKER
& AREA (AC)
10-FEET BUFFER FROM
UNDERGROUND STRUCTURE
\\1-IERE INFlL TRA TION IS NOT
RECOMMENDED PER
GEOTECHNICAL REPORT
CONCRETE PAVER BAND
PER LANDSCAPE PLAN
4" THICK CONCRETE
PA VER BLOCK PER
LANDSCAPE PLAN
------------xxx ----------------------xxx __ __
---xxx ..
--+➔➔➔➔-
ffi
~ ~
6" ASTM #2 AGGREGATE
3" ABOVE BOTTOM
4" DIA PERFORATED SUBDRAIN. PERFORATED HOLES
3/8" f MIN @ 3-1/4" SPACING ALONG PIPE,
W/ STAGGERED HORIZONTAL ROWS. PER CITY OF SAN
DIEGO STANDARD DRAWING SDSW-102.
1. ALL STONE LAYERS MUST BE CLEAN AND FREE OF FINE GRANULAR MATERIAL
DATE IN\TlAL
2. PERVIOUS CONCREIE AND/OR PAVERS SHALL BE INSTALLED PER MANUFACTURER
SPECIFICATIONS.
DMA EXHIBIT
[2]1 CITY OF CARLSBAD I[!]
FRONT PORCH MEMORY CAFE AND IIIDEPENDENT LIVING
DMA/SINGLE SHEET BMP SITE PLAN
DATE INITIAL
REVISION DESCRIPTION OTHER APPROVAL CITY APPROVAL
SD
W
W
W
S
S
S
S
S S SS
OHE
OHE
OHE
OH
E
OH
E
OH
E
OH
E
OH
E
OHE OHE OHE
W W
W
W
W
W
S
S
S
S
S
S
S
S
S
S
S
W
W
W
W
W
W
W
S S S
W
51
9449 BALBOA AVE, STE 270
SAN DIEGO, CA 92123 619.299.5550BWE JOB NO. 13913US1.00
ENGINEERING DEPARTMENT
2710, 2720, 2730, & 2740 OCEAN STREET
CARLSBAD, CA. 92008
SITE DESIGN BMPS:
SOURCE CONTROL BMPS:
LEVEL 1
GARAGE
PERMEABLE PAVEMENT & LINER DETAILNOT TO SCALE
MATCHLINE SHEET 1
MA
T
C
H
L
I
N
E
S
H
E
E
T
1
SD
n
2
C
I
L
=
0
C
c:
CJ n
C u
C' ,c
Q_
I
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:,: a. "' <
MH
3.9
.3
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~=-i~+-«>
52 CONC
ENCASED
I< SWR ~,-..
~'? ..
~ ,..,
~
REQUIRED IMPERVIOUS AREA = OFF-1 + OFF-2 + OFF-4 = 0.053 + 0.035 + 0.014 = 0.102 ACRE = 4,418 SF
EXCESS IMPERVIOUS AREA = 5,490 SF
I 5,490 SF > 4,418 SF
I
qi'? ..
pp
'\ ~~-..
R DWG 195-
I
. I
I ~"""' • • ' "
!;" s
.. .• I , . , .
I ... -..
,.,,1,1..:1
.. DMA Unique Identifier Area (acres)
A-1 0.053
A-2 0.082
A-3 0.034
A-4 0.136
A-5 0.083
A-6 0.049
A-7 0.130
B-1 0.010
8-2 0.005
8-3 0.019
8-4 0.017
TOTAL 0.618
OFF-1 0.053
OFF-2 0.035
OFF-3 0.054
OFF-4 0.042
TOTAL OFFSITE 0.184
Tabular Summary of DMAs I Worksheet B-1
Im per vi ous Area (acres) %Imp HSG Area Weighted Runoff Coefficient (C) DCV (cubic feet) Mitigated By (BM PI D) Pollutant Control Type
0.052 99.3% B 0.894 103 BMP#3 BF-3 Proprietary Biofiltration
0.074 90.2% B 0.822 150 BMP#4 BF-3 Proprietary Biofiltration
0.024 70.6% B 0.665 49 BMP#2 BF-3 Proprietary Biofiltration
0.136 99.7% B 0.898 267 01v1t-'ll'2 BF-3 Proprietary Biofiltration
0.074 89.2% B 0.813 148 BM P# 1 BF-3 Proprietary Biofiltration
0.049 100.0% B 0.900 96 BMP#5 BF-3 Proprietary Biofiltration
0.082 63.1% B 0.605 175 BMP#5 BF-3 Proprietary Biofiltration
0.008 82.2% B 0.757 17 TreeWell#2 0th er
0.005 100.0% B 0.900 -De-minimis De-minimis
0.014 73.8% B 0.690 29 BMP#6 I NF-3 Pervious Pavers
0.010 61.4% B 0.591 22 BMP#7 INF-3 Pervious Pavers
0.529 85.6% B 0.785 1,056 --
0.053 100.0% B 0.900 103 -SSD-BM P Tree Wei I # 1
0.035 100.0% B 0.900 68 -SSD-BM P Tree Wei I# 1
0.040 73.8% B 0.690 82 -SSD-BM P Tree Wei I # 1
0.023 55.6% B 0.545 50 -SSD-BM P Tree Wei I # 1
0 .151 82.1% B 0.757 303 --
~-✓ ~ /,__,
5 0 10 B\V E
20 CIVIL •STRUCTURAL•SURVEY• PLANNING
SCALE IN FEET DATE INITIAL
1 inch = 10 ft. ENGINEER OF WORK
Drainsto(POCID)
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
CT 2022-0003/CUP 2022-0014/CDP 2022-0047 (DEV2022-0063)
PARTY RESPONSIBI E FOR MAINTENANCE
NAME FRONT PORCH COMMUNITIES
ADDRESS BOO NORTH BRAND BLVD. CONTACT JOAN JOHNSON
191H FLOOR
GLENDALE, CA 92103
PHONE NO .. ~m~o _____ _
PLAN PREPARED BY:
NAME HECTOR MAYTORENA
COMPANY...,B,,,WE..._.l...,NC..._ ___ _ SIGNATURE
ADDRESS 2449 BALBOA AVENUE
SUIJE 270
SAN DIEGO, CA 92123
PHONE NO. 619 299 5550 CERTIFlCA TION RCE 86216
BMP NOTES
1. THESE BMPS ARE MANDATORY TO BE INSTALLED PER
MANUFACTURER'S RECOMMENDATIONS OR THESE PLANS.
2. NO CHANGES TO THE PROPOSED BMPS ON THIS SHEET
WITHOUT PRIOR APPROVAL FROM THE CITY ENGINEER.
3. NO SUBSTITUTIONS TO THE MA lERIAL OR TYPES OR
PLANTING TYPES 1'11THOUT PRIOR APPROVAL FROM THE CITY
ENGINEER.
4. NO OCCUPANCY 1'11LL BE GRANlED UNTIL THE CITY
INSPECTION STAFF HAS INSPECTED THIS PROJECT FOR
APPROPRIATE BMP CONSTRUCTION AND INSTALLATION.
5. REFER TO MAINTENANCE AGREEMENT DOCUMENT.
6. SEE PROJECT SWMP FOR ADDITIONAL INFORMATION.
@ OVERHEAD COVERING
-MATERIALS & EQUIPMENT STORAGE
@ SEPARATION FLOWS FROM ADJACENT AREAS
-MATERIALS & EQUIPMENT STORAGE
STORM DRAINS AND CATCH BASINS
1'11LL BE LABELED 1'11TH STENCILING
OR SIGNAGE TO DISCOURAGE
DUMPING
! SD-B ! DIRECT RUNOFF TO PERVIOUS AREAS
-SIDEWALKS & WALKWAYS
-DRII/EWA YS
-PATIOS, DECKS, & COURTYARDS
-ROOFTOP AREAS
I SD-I I CONSTRUCT SURFACES FROM PERMEABLE MATERIALS
-PARKING AREAS & WALKWAYS
-PATIOS, DECKS, & COURTYARDS
I SD-KI SUSTAINABLE LANDSCAPING
STRUCTURAL BMP KEYNOlES
VCOMPACT PROPRIETARY BIOFILTRATION BMP (POLLUTANT CONTROL)
V PERMEABLE PAVEMENT BMP (POLLUTANT CONTROL)
SWOMP NOlES
1. THE SllE IS COMPRISED OF HYDROLOGIC
SOIL TYPE B.
2. APPROXIMA 1E DEPTH TO GROUNDWATER
GREATER THAN 30 FEET
3. EXISTING NA TUR AL HYDROLOGIC FEATURES
-NOT APPLICABLE
4. NO CRITICAL COARSE SEDIMENT YIELD
AREAS ARE NOT PRESENT ON SllE
5. PROJECT DISCHARGES DIRECTLY INTO
HARDENED CONVEYANCE AND ROUTED
DIRECTLY TO THE PACIFIC OCEAN.
PROJECT IS HYDROMODIFICA TION EXEMPT.
PROPOSED
BUILDING/
STRUCTURE
BMP CONSTRUCTION AND
INSPECTION NOTES
THE EOW WILL VERIFY THAT PERMANENT BMPS ARE
CONSTRUCTED AND OPERA TING IN COMPLIANCE 1'11TH THE
APPLICABLE REQUIREMENTS. PRIOR TO OCCUPANCY THE EOW
MUST PROVIDE:
1. PHOTOGRAPHS OF THE INSTALLATION OF PERMANENT
BMPS PRIOR TO CONSTRUCTION, DURING CONSTRUCTION,
AND AT FINAL INSTALLATION.
2. A WET STAMPED LETTER VERIFYING THAT PERMANENT
BMPS ARE CONSTRUCTED AND OPERATING PER THE
REQUIREMENTS OF THE APPROVED PLANS.
3. PHOTOGRAPHS TO VERIFY THAT PERMANENT WATER
QUALITY TREATMENT SIGNAGE HAS BEEN INSTALLED.
PRIOR TO RELEASE OF SECURITIES, THE DEVIELOPER IS
RESPONSIBLE FOR ENSURING THE PERMANENT BMPS HA VIE NOT
BEEN REMOVED OR MODIFIED BY THE NEW HOMEOWNER OR HOA
1'11THOUT THE APPROVAL OF THE CITY ENGINEER.
LEGEND SYMBOL
PROPERTY LINE/RIGHT-OF-WAY
CENTER LINE
-ROW - - -P/L---C/L-----
AC PAVIEMENT
AC PAVEMENT GRIND & OVERLAY
CONCRETE PAVIEMENT
PAI/ERS
NEW CATCH BASIN SIZE PER PLAN
NEW AREA DRAIN
NEW ROOF DRAIN PER PLUMBING PLAN
NEW SEWER/STORM DRAIN CLEANOUT
SITE WALL I I I I I I I I I
STORM DRAIN
MODULAR WETLAND
12" TRENCH DRAIN
STORM DRAIN CLEANOUT TYPE A4
STREET TREE BOX
SUMP PUMP
ROOF DRAIN DA YUGHTS TO
BMP PER PLUMBING PLANS
□
[Q]
PERMEABLE PA VERS 11 I I I I I I ~
PROJECT OUTER DMA BOUNDARY
DMA BOUNDARY
EXISTING CONTOUR
NEW CONTOUR
FLOW DIRECTION
FLOW PATH
POINT OF COMPLIANCE (POC)
DRAINAGE MANAGEMENT AREA MARKER
& AREA (AC)
10-FEET BUFFER FROM
UNDERGROUND STRUCTURE
\\1-IERE INFlL TRA TION IS NOT
RECOMMENDED PER
GEOTECHNICAL REPORT
CONCRETE PAVER BAND
PER LANDSCAPE PLAN
4" THICK CONCRETE
PA VER BLOCK PER
LANDSCAPE PLAN
-------------xxx ------------_.,.---------xxx ---xxx ..
-+ ➔ ➔ ➔ ➔ -
ffi
~ X
6" ASTM #2 AGGREGATE
3" ABOVE BOTTOM
4" DIA PERFORATED SUBDRAIN. PERFORATED HOLES
3/8" f MIN @ 3-1/4" SPACING ALONG PIPE,
NOTES: SUBGRADE
W/ STAGGERED HORIZONTAL ROWS. PER CITY OF SAN
DIEGO STANDARD DRAWING SDSW-102.
1. ALL STONE LAYERS MUST BE CLEAN AND FREE OF FINE GRANULAR MATERIAL
DATE INITIAL
2. PERVIOUS CONCRETE AND/OR PAVERS SHALL BE INSTALLED PER MANUFACTURER
SPECIFICATIONS.
DMA EXHIBIT
01 CITY OF CARLSBAD I[!]
FRONT PORCH MEMORY CAFE AND IIIDEPENDENT LIVING
DMA/SINGLE SHEET BMP SITE PLAN
DATE INITIAL
REVISION DESCRIPTION OTHER APPROVAL CITY APPROVAL