HomeMy WebLinkAboutCT 2019-0006; 2690 ROOSEVELT; STORM WATER QUALITY MANAGEMENT PLAN (SWQMP); 2020-01-31I '7 J
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CITY OF CARLSBAD
PRIORITY DEVELOPMENT PROJECT (PDP)
STORM WATER QUALITY MANAGEMENT PLAN (SWQMP)
FOR
2690 ROOSEVELT STREET
HMP19-
(DWG_-_)
SWQMP No.
ENGINEER OF WORK:
RANDY R. BROWN RCE 36190
PREPARED FOR:
KITCHELL DEVELOPMENT CO.
1555 CAMINO DEL MAR, STE 307
DEL MAR, CA 92014
(858) 947-5224
:city ofCarlsbad
MAR 0-2)020
PREPARED BY:
SOWARDS & BROWN ENGINEERING, INC
2187 NEWCASTLE AVE, STE 103
CARDIFF, CA 92007
(760)436,-8500
DATE:
JANUARY 31, 2020
tlanning Division
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 1 a: OMA Exhibit
Attachment 1 b: Tabular Summary of DMAs and Design Capture Volume Calculations
Attachment 1c: Harvest and Use Feasibility Screening (when applicable)
Attachment 1d: Categorization of Infiltration Feasibility Condition (when applicable)
Attachment 1 e: Pollutant Control BMP Design Worksheets / Calculations
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
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CERTIFICATION PAGE
Project Name: 2690 ROOSEVELT
Project ID: MAP 20-
1 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 th~t 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 36190, Expires 6/30/20
f Work's Signature, PE Number & Expiration Date
Randy R. Brown
Print Name
Sowards & Brown Engineering, Inc.
Company
January 31, 2020
Date
PROJECT VICINITY MAP
VICINITY MAP
CITY OF OCEANSIDE
/8
!\JOT TO s I TE _________,",,.,.___ SCALE
PACIFIC
OCEAN
Cl
CITY OF ENCINITAS
MARCOS
OF
( City of
Carlsbad
STORM WATER STANDARDS
QUESTIONNAIRE
Development Services
Land Development Engineering
1635 Faraday Avenue
(760) 602-2750
www.carlsbadca.gov
E-34
j 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 or be subject to 'PRIORITY
DEVELOPMENT PROJECT' (PDP) 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: 2690 Roosevelt PROJECT ID:
ADDRESS: 2690 Roosevelt Street APN : 203-102-15
The project is (check one): D New Development [XI Redevelopment
The total proposed disturbed area is: 19,135 ft2 ( 0.44 ) acres
The total proposed newly created and/or rep laced impervious area is: _ 12,502 _ ft2 (_Q.29 __ ) 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.
E-34 Page 1 of 4 REV02/16
8TEP1
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 □ [ZJ or structure that do not alter the size (See Section 1.3 of the BMP Design Manual for guidance)?
If you answered "yes" to the above question, provide justification below then go to Step 5, mark the third 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.
8TEP2
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; □ [X] b) Designed and constructed to be hydraulically disconnected from paved streets or roads;
c) Designed and constructed with permeable pavements or surfaces in accordance with USEPA
Green Streets guidance?
2. Retrofitting or redeveloping existing paved alleys, streets, or roads that are designed and constructed in □ [ZJ accordance with the USEPA Green Streets guidance?
3. Ground Mounted Solar Array that meets the criteria provided in section 1.4.2 of the BMP manual? □ ~
If you answered "yes" to one or more of the above questions, provide discussion/justification below, then go to Step 5, 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 04/17
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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, IX] □
and public development projects on public or private land.
2. Is your project a redevelopment project creating and/or replacing 5,000 square feet or more of
impervious surface collectively ove r the entire project site on an existing site of 10,000 square feet or □ [X] more of impervious surface? This includes commercial, industrial, residential, mixed-use, and public
development projects on public or private land.
3. Is you r project a new or redevelopment project that creates and/or replaces 5,000 square feet or more
of impervious surface co llectively over th e entire project site and supports a restaurant? A restaurant is
a facility that sells prepared foods and drin ks for consumption , including stationary lunch counters and □ IX]
refreshment stands selling prepared foods and drinks for immediate consumption (Standard Industrial
Classification (SIC) code 581 2).
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.
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 th e entire project site and supports a parking lot? A parking lot is □ IX] a land area or facility for the temporary parking or storage of motor vehicles used personally for
business or for commerce.
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 □ IX] site? A street, road, highway, freeway or driveway is any paved impervious surface used for the
transportation of automobiles, trucks, motorcycles, and other vehicles.
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 □ IX]
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 comminqled with flows from adjacent lands).*
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 □ IZl shop is a facility that is categorized in any one of the following Standard Industrial Classification (SIC)
codes: 5013, 5014, 554 1, 7532-7534, or 7536-7539.
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 □ IX] RGO's that meet the follo wing criteria: (a) 5,000 square feet or more or (b) a project Average Daily
Traffic (ADT) of 100 or more vehicles per day.
10. Is your project a new or redevelopment project that results in the disturbance of one or more acres of land □ IX] and are expected to generate pollutants post construction?
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 □ 00
21 .203.040)
If you answered "yes" to one or more of the above questions, your project is a PDP. If you r project is a redevelopment
project, go to step 4. If your project is a new project, go to step 5, check the first box stating "My project is a PDP ... "
and complete applicant information .
If you answered "no" to all of the above questions, your project is a 'STANDARD PROJECT.' Go to step 5, check the
second box stating "My project is a 'STANDARD PROJECT ... " and complete applicant information.
E-34 Page 3 of 4 REV 04/17
STEP4
TO BE COMPLETED FOR REDEVELOPMENT PROJECTS ntAT ARE PRIORITY DEVELOPMENT PROJECTS (PDP)
ONLY
Complete the questions below regarding your redevelopment project (MS4 Permit Provision E.3.b.(2)):
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)= 3,821 sq . ft.
Total proposed newly created or replaced impervious area (B) = _12,502 ________ sq. ft.
Percent impervious area created or replaced (B/A)*100 = _327 ___ %
YES NO
□ IX]
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, check the first box stating "My project is a PDP ... " and complete
applicant information.
If you answered "no," the structural BMP's required for PDP apply to the entire development. Go to step 5, check the
check the first box statin "M ro·ect is a PDP ... " and com lete a licant information.
STEPS
CHECK THE APPROPRIATE BOX AND COMPLETE APPLICANT INFORMATION
IX! My 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) for submittal at time of application .
0 My project is a 'STANDARD PROJECT' OR EXEMPT from PDP and must only comply with 'STANDARD PROJECT'
stormwater requirements of the BMP Manual. As part of these requirements, I will submit a "Standard Project
Requirement Checklist Form E-36" and incorporate low impact development strategies throughout my project.
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.
D My Project is NOT a 'development project' and is not subject to the requirements of the BMP Manual.
Applicant Information and Signature Box
Applicant Title: 4..,\/' :p.,
Date: January 31 , 2020
• Environmentally Sensitive Are s 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.
This Box for City Use Onlv
YES NO
City Concurrence: □ □
By:
Date:
Project ID:
E-34 Page 4 of 4 REV 04/17
I
SITE INFORMATION CHECKLIST
P. _: __ : Sunvnary lnfonnatlon
Project Name 2690 ROOSEVELT
Project ID
Project Address 2690 Roosevelt Street
Carlsbad , CA 92008
Assessor's Parcel Number(s) (APN(s)) 203-102-15
Project Watershed (Hydrologic Unit) Carlsbad 904
Parcel Area 0.44 Acres ( 19,135 Sauare Feet)
Existing Impervious Area 0.09 3,821 (subset of Parcel Area) Acres ( Square Feet)
Area to be disturbed by the project 0.44 (Project Area) Acres ( 19,135 Square Feet)
Project Proposed Impervious Area
(subset of Project Area) ~.30 Acres ~2,502 __ Square Feet)
Project Proposed Pervious Area
(subset of Project Area) 0.14 Acres (_6,633 __ Square Feet)
Note: Proposed Impervious Area + Proposed Pervious Area = Area to be Disturbed by the
Project.
This mav be less than the Parcel Area.
Description of Exlstlna Site Condition and Drainage Patterns
Current Status of the Site (select all that apply):
X Existing development
D Previously graded but not built out
□ Agricultural or other non-impervious use
D Vacant, undeveloped/natural
Description/ Additional Information:
Single family residence with attached garage, shed in back yard .
Existing Land Cover Includes (select all that apply):
X Vegetative Cover
D Non-Vegetated Pervious Areas
x Impervious Areas
Description / Additional Information:
Established ground cover and trees. Concrete driveway and walkways.
Underlying Soil belongs to Hydrologic Soil Group (select all that apply):
D NRCS Type A
XNRCS Type 8
D NRCS Type C
D NRCS Type D
Approximate Depth to Groundwater (GW):
D GW Depth < 5 feet
X 5 feet < GW Depth < 1 0 feet
D 1 0 feet < GW Depth < 20 feet
GW Depth > 20 feet
Existing Natural Hydrologic Features (select all that apply):
D Watercourses
D Seeps
D Springs
□Wetlands
X None
Description / Additional Information:
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]:
The existing site is a 0.44 acre property at 2690 Roosevelt Street. The site is flat, with a
slight slope Westerly to Roosevelt Street. There is a single family residence with a
driveway and 2 car garage. The site is covered with established groundcover and several
trees. There are no existing stormwater conveyance systems.
There is offsite runoff from the neighboring property to the southeast, consisting mainly of
runoff from the nearest roof. A portion of the site drains to the vacant lot to the northwest
before flowing to Roosevelt Street. There is a curb inlet in front of the property which
collects flow from the existing curb and gutter running northeast.
Description of p _ __. Site Development and Dralnaae Pattema
Project Description / Proposed Land Use and/or Activities:
Remove existing residence, hardscape and landscape and build 3 multi-unit residential
buildings. A total of 9 condominiums will reside within the 3 buildings, each with an
individual garage. Permeable pavement will be used for the driveway and most of the
walkways.
List/describe proposed impervious features of the project (e .g., buildings, roadways , parking
lots, courtyards, athletic courts, other impervious features):
There will be three buildings with decks and roof overhangs.
List/describe proposed pervious features of the project (e.g., landscape areas):
There are many planters and landscape areas surrounding the four buildings, as well as
narrow back yards east of the buildings. Permeable pavement will be used for the driveway
and most of the walkways. There are four biofiltration basins to treat roof runoff.
Does the project include grading and changes to site topography?
~Yes
□No
Description/ Additional Information:
The existing grades will be cut to provide a flatter surface for the three buildings
and driveway.
Does the project include changes to site drainage (e.g., installation of new storm water
conveyance systems)?
(gl Yes
□No
Description/ Additional Information:
Five biofiltration basins will be installed to treat runoff from the proposed roofs. The
drainage from the basins and surface runoff will be piped to a pump vault and pumped to a
relocated curb inlet in Roosevelt Street. Runoff from the front yard will flow over the
surface consistent with existing drainage patterns. There is a reduction in offsite flow to
the vacant lot to the northwest.
Identify whether any of the following features, activities, and/or pollutant source areas will be
present (select all that apply):
o(J On-site storm drain inlets
D Interior floor drains and elevator shaft sump pumps
□ Interior parking garages
Ii Need for future indoor & structural pest control
X Landscape/Outdoor Pesticide Use
□ Pools, spas, ponds, decorative fountains, and other water features
□ Food service
D Refuse areas
□ Industrial processes
□ Outdoor storage of equipment or materials
D Vehicle and Equipment Cleaning
□ Vehicle/Equipment Repair and Maintenance
□ Fuel Dispensing Areas
□ Loading Docks
P() Fire Sprinkler Test Water
□ Miscellaneous Drain or Wash Water
D Plazas, sidewalks, and parking lots
ldentlflcatlon 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):
Drainage from the site flows Northerly along Roosevelt Street to drain inlets, then is piped to Buena
Vista Lagoon.
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
Buena Vista Lagoon Sediment, Nutrients, Bacteria
Identification of Project Site Pollutants
Identify pollutants anticipated from the project site based on all proposed use(s) of the site (see
BMP Design Manual Appendix 8.6):
Also a Receiving
Not Applicable to Anticipated from the Water Pollutant of
Pollutant the Project Site Project Site Concern
Sediment X X
Nutrients X X
Heavy Metals X
Organic Compounds X
Trash & Debris X
Oxygen Demanding
X Substances
Oil & Grease X
Bacteria & Viruses X X
Pesticides X
H dromodlftcatlon Mana
Do hydromodification management requirements apply (see Section 1.6 of the BMP Design
Manual)?
D Yes, hydromodification management flow control structural BMPs required .
IX 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.
D 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.
D 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):
This lot is within an area defined by the City of Carlsbad as being hydromodification exempt.
Crltlcal Coarse Sediment Yleld Areas*
"Thia Section on romodlflcatlon ma ulrementsa
Based on the maps provided within the WMAA, do potential critical coarse sediment yield areas
exist within the project drainage boundaries?
□Yes
D No, No critical coarse sediment yield areas to be protected based on WMAA maps
If yes, have any of the optional analyses presented in Section 6.2 of the BMP Design Manual
been performed?
D 6.2.1 Verification of Geomorphic Landscape Units (GLUs) Onsite
D 6.2.2 Downstream Systems Sensitivity to Coarse Sediment
D 6.2.3 Optional Additional Analysis of Potential Critical Coarse Sediment Yield Areas Onsite
D 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
D Critical coarse sediment yield areas exist but additional analysis has determined that
protection is not required. Documentation attached in Attachment 8 of the SWQMP.
D Critical coarse sediment yield areas exist and require protection. The project will implement
management measures described in Sections 6.2.4 and 6.2.5 as applicable, and the areas
are identified on the SWQMP Exhibit.
Discussion/ Additional Information:
Flow Control for Poat.Project Runoff'
.,... .. Section on ulnNI If romodlftcatlon ma ulrements •
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)?
D No , the low flow threshold is 0.102 (default low flow threshold)
D Yes , the result is the low flow threshold is 0.102
D Yes, the result is the low flow threshold is 0.302
D Yes, the result is the low flow threshold is 0.502
If a geomorphic assessment has been performed, provide title, date, and preparer:
Discussion/ Additional Information: (optional)
Other Site Reaulrementa 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 Addltlonal lnfonnatlon or Continuation of Previous Sections As Needed
This space provided for additional information or continuation of information from previous
sections as needed.
[Insert City's Standard Project Requirement Checklist Form E-36 (here)]
SUMMARY OF PDP STRUCTURAL BMPS
C cityof
Carlsbad
Project Name: 2690 ROOSEVELT
Project ID:
DWG No. or Building Permit No.:
STANDARD PROJECT
REQUIREMENT
CHECKLIST
E-36
Project lnfonnatlon
Source Control 811Pa
Development Services
land Development Engineering
1635 Faraday Avenue
(760) 602-2750
www.carlsbadca.gov
All development projects must implement source control BMPs SC-1 through SC-6 where applicable and feasible. See
Chapter 4 and Appendix E.1 of the BMP Design Manual (Volume 5 of City Engineering Standards) for information to
implement source control BMPs shown in this checklist.
Answer each category below pursuant to the following .
• "Yes" means the project will implement the source control BMP as described in Chapter 4 and/or Appendix E.1 of the
Model BMP Design Manual. Discussion/justification is not required .
• "No" means the BMP is applicable to the project but it is not feasible to implement. Discussion/justification must be
provided. Please add attachments if more space is needed.
• "N/A" means the BMP is not applicable at the project site because the project does not include the feature that is
addressed by the BMP (e.g., the project has no outdoor materials storage areas). Discussion/justification may be
provided.
Source Control Requirement Applied?
SC-1 Prevention of Illicit Discharges into the MS4 Ii] Yes □ No □ N/A
Discussion/justification if SC -1 not implemented :
SC-2 Storm Drain Stenciling or Signage Iii Yes □ No □ N/A
Discussion/justification if SC -2 not implemented :
SC-3 Protect Outdoor Materials Storage Areas from Rainfall, Run-On, Runoff, and Wind □ Yes □ No lil NIA Dispersal
Discussion/justification if SC-3 not implemented:
No outdoor materials storage areas
E-36 Page 1 of 4 Revised 09/16
Source Control Raaulrement (continued) a --·1
SC-4 Protect Materials Stored in Outdoor Work Areas from Rainfall, Run-On, Runoff, and □Yes 0 No Iii N/A Wind Dispersal
Discussion/justification if SC-4 not implemented:
No outdoor work areas
SC-5 Protect Trash Storage Areas from Rainfall , Run-On, Runoff, and Wind Dispersal D Yes D No lil N/A
Discussion/justification if SC-5 not implemented:
No outdoor trash storage areas
SC-6 Additional BMPs based on Potential Sources of Runoff Pollutants must answer for each source listed below and
identify additional BMPs. (See Table in Aooendix E.1 of BMP Manual for quidance).
Iii On-site storm drain inlets li]Yes D No D N/A
D Interior floor drains and elevator shaft sump pumps □Yes D No Iii N/A
D Interior parking garages □ Yes D No Iii N/A
Iii Need for future indoor & structural pest control Iii Yes 0 No D N/A
Iii Landscape/Outdoor Pesticide Use li]Yes 0 No 0 N/A
D Pools, spas, ponds, decorative fountains, and other water features D Yes 0 No lil N/A
D Food service □ Yes 0 No Iii N/A
D Refuse areas D Yes D No lil N/A
D Industrial processes D Yes 0 No lil N/A
D Outdoor storage of equipment or materials □ Yes 0 No Iii N/A
D Vehicle and Equipment Clean ing □Yes D No Ii] N/A
D Vehicle/Equipment Repair and Maintenance □Yes D No Ii] N/A
D Fuel Dispensing Areas □Yes D No lil N/A
□ Loading Docks D Yes 0 No Iii N/A
Iii Fire Sprinkler Test Water 1iJ Yes D No D N/A
D Miscellaneous Drain or Wash Water D Yes D No Iii N/A
D Plazas, sidewalks, and parkinq lots D Yes 0 No Iii NIA
For "Yes" answers, identify the additional BMP per Appendix E.1 . Provide justification for "No" answers.
On-site storm drain inlets will be labeled with "Do not dump" signs
Pest control and pesticide use will employ owner education only.
Fire sprinkler test water will be disposed per City of Carlsbad recommendations.
E-36 Page 2 of 4 Revised 09/16
Site DNlgn BMPa
All development projects must implement site design BMPs SD-1 through SD-8 where applicable and feasible. See
Chapter 4 and Appendix E.2 thru E.6 of the BMP Design Manual (Volume 5 of City Engineering Standards) for information
to implement site design BMPs shown in this checklist.
Answer each category below pursuant to the following .
• "Yes" means the project will implement the site design BMPs as described in Chapter 4 and/or Append ix E.2 thru E.6 of
the Model BMP Design Manua l. Discussion / justification is not required.
• "No" means the BMPs is applicable to the project but it is not feasible to implement. Discussion/justification must be
provided. Please add attachments if more space is needed.
• "NIA" means the BMPs is not applicable at the project site because the project does not include the feature that is
addressed by the BMPs (e.g., the project site has no existing natural areas to conserve). Discussion/justification may be
provided.
Site DNlgn Requirement I Applied?
SD-1 Maintain Natural Dra inage Pathways and Hydrologic Features I Ii] Yes I □ No I □ N/A
Discussion/justification if SD-1 not implemented:
SD-2 Conserve Natu ral Areas, Soils, and Vegetation I □ Yes I Iii No I □ N/A
Discussion/justification if SD-2 not implemented:
Entire site to be disturbed
SD-3 Minimize Impervious Area I lil Yes I □ No I □ N/A
Discussion/justificati on if SD-3 not implemented:
Permeable driveways and walkways will be utilized.
SD-4 Minimize Soil Compaction I □ Yes I Iii No I □ N/A
Discussion/justification if SD-4 not implemented :
Entire site to be disturbed.
SD-5 Impervious Area Dispersion I Iii Yes I □ No IO N/A
Discussion/justification if SD-5 not implemented:
Impervious areas drain to landscaping or permeable walkways for treatment.
E-36 Page 3 of 4 Revised 09/1 6
Site l>Nlan Requirement (continued) I ADDlled?
SD-6 Runoff Collection I ~Yes I 0 No I □ N/A
Discussion/justification if SD-6 not implemented:
Roof drains piped directly to biofiltration basins for treatment and peak runoff reduction.
SD-7 Landscaping with Native or Drought Tolerant Species I il Yes I □ No I □ N/A
Discussion/justification if SD-7 not implemented:
See landscape plans for details.
SD-8 Harvesting and Using Precipitation I D Yes I il No I D NIA
Discussion/justification if SD -8 not implemented:
Insufficient landscaping or water demand to justify harvesting. See the BMP sizing worksheet in
attachment 1 e for details.
E-36 Page 4 of 4 Revised 09/16
PDP Structural 811Pa
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). Both
storm water pollutant control and flow control for hydromodification management can 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, indicate whether
pollutant control and flow control BMPs are integrated together or separate.
Five biofiltration basins will be installed to treat runoff from the proposed roofs. The basins
are sized to infiltrate the DVC as well as increased peak runoff from 100 year storms. The
drainage from the basins and surface drainage will be piped to a pump vault then pumped
to a relocated curb inlet in Roosevelt Street. Runoff from the front yard will flow over the
surface consistent with existing drainage patterns. There is a reduction in offsite flow to the
vacant lot to the northwest.
Runoff from impervious surfaces will be routed to the proposed yards for treatment and
infiltration. There are impermeable surfaces adjacent to the public sidewalk that cannot be
effectively treated and are marked as 'De Miminis'.
[Continue on next page as necessary.]
[Continued from previous page -This page is reserved for continuation of description of general
strategy for structural BMP implementation at the site.]
Structural BMP Summary lnfonnatlon
[Copy this page • needed to provide lnfonnatlon for each lndlvldual proposed
structural BMPl
Structural BMP ID No. BMP 1
DWG Sheet No. 1
Type of structural BMP:
□ Retention by harvest and use (HU-1 )
□ Retention by infiltration basin (INF-1)
□ Retention by bioretention (INF-2)
D Retention by permeable pavement (INF-3)
Partial retention by biofiltration with partial retention (PR-1 )
Kl Biofiltration (BF-1)
D 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)
D Detention pond or vault for hydromodification management
D Other (describe in discussion section below)
Purpose:
® Pollutant control only
□ Hydromodification control only
D Combined pollutant control and hydromodification control
D Pre-treatment/forebay for another structural BMP
D Other (describe in discussion section below)
Discussion (as needed):
Drainage from adjacent roof area will be collected and treated in this basin. Once the
basin is filled, the ra inwater is piped to a pump vault then pumped to a relocated drain
inlet in Roosevelt Street. The basin is lined to prevent infiltration of water next to the
building foundation and has a perforated underdrain. A flow restrictor will be used to
meet detention and peak flow reduction requirements. See the included basin detail 1
for additional information. See the included basin detail 1 for additional information.
The five biofiltration basins are sized to accommodate the 100 year peak flow increase
from the site. See the drainage study for details.
Structural BIIP SWnmary lnfonnatlon
[Copy this page • needed to provide Information for each Individual propoNd
structural BIIPJ
Structural BMP ID No. BMP 2
DWG Sheet No. 1
Type of structural BMP:
D Retention by harvest and use (HU-1)
o Retention by infiltration basin (I NF-1)
D Retention by bioretention (INF-2)
□ Retention by permeable pavement (INF-3)
Partial retention by biofiltration with partial retention (PR-1)
Kl Biofiltration (BF-1)
□ 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)
D Detention pond or vault for hydromodification management
□ Other (describe in discussion section below)
Purpose:
® Pollutant control only
□ Hydromodification control only
D Combined pollutant control and hydromodification control
D Pre-treatment/forebay for another structural BMP
D Other (describe in discussion section below)
Discussion (as needed):
Drainage from adjacent roof area will be collected and treated in this basin . Once the
basin is filled , the rainwater is piped to a pump vault then pumped to a relocated drain inlet
in Roosevelt Street. The basin is lined to prevent infiltration of water next to the building
foundation and has a perforated underdrain. A flow restrictor will be used to meet
detention and peak flow reduction requirements. See the included basin detail 1 for
additional information. See the included basin detail 2 for additional information.
The five biofiltration basins are sized to accommodate the 100 year peak flow increase
from the site. See the drainage study for details.
Structural BIIP Summary lnfonnatlon
[Copy this page • needed to provide lnfonnatlon for each lndlvldual propoNd
structural BIIP]
Structural BMP ID No. BMP 3
DWG Sheet No. 1
Type of structural BMP:
□ Retention by harvest and use (HU-1)
D Retention by infiltration basin (INF-1)
D Retention by bioretention (INF-2)
D Retention by permeable pavement (INF-3)
Partial retention by biofiltration with partial retention (PR-1)
XI Biofiltration (BF-1)
D 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
□ Other (describe in discussion section below)
Purpose:
~ Pollutant control only
o Hydromodification control only
D Combined pollutant control and hydromodification control
D Pre-treatment/forebay for another structural BMP
D Other (describe in discussion section below)
Discussion (as needed):
Drainage from adjacent roof area will be collected and treated in this basin. Once the
basin is filled , the rainwater is piped to a pump vault then pumped to a relocated drain inlet
in Roosevelt Street. The basin is lined to prevent infiltration of water next to the building
foundation and has a perforated underdrain. A flow restrictor will be used to meet
detention and peak flow reduction requirements. See the included basin detail 1 for
additional information. See the included basin detail 2 for additional information.
The five biofiltration basins are sized to accommodate the 100 year peak flow increase
from the site. See the drainage study for details.
Structural BIIP Summary lnfonnatlon
[Copy this page • needed to provide lnfonnatlon for each lndlvldual proposed
structural BMP]
Structural BMP ID No. BMP 4
DWG Sheet No. 1
Type of structural BMP:
D Retention by harvest and use (HU-1 )
D Retention by infiltration basin (INF-1)
D Retention by bioretention (INF-2)
D Retention by permeable pavement (INF-3)
Partial retention by biofiltration with partial retention (PR-1)
Kl Biofiltration (BF-1)
D Flow-thru treatment control included as pre-treatmenUforebay 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)
D Detention pond or vault for hydromodification management
D Other (describe in discussion section below)
Purpose:
~ Pollutant control only
D Hydromodification control only
D Combined pollutant control and hydromodification control
D Pre-treatment/forebay for another structural BMP
D Other (describe in discussion section below)
Discussion (as needed):
Drainage from adjacent roof area will be collected and treated in this basin. Once the
basin is filled , the rainwater is piped to a pump vault then pumped to a relocated drain
inlet in Roosevelt Street. The basin is lined to prevent infiltration of water next to the
building foundation and has a perforated underdrain. A flow restrictor will be used to meet
detention and peak flow reduction requirements. See the included basin detail 1 for
additional information. See the included basin detail 2 for additional information .
The five biofiltration basins are sized to accomodate the 100 year peak flow increase from
the site. See the drainage study for details.
Structural BIIP Summary lnfonnatlon
[Copy this page • IINded to provide lnfonnatlon for each lndlvldual proposed
structural BIIPl
Structural BMP ID No. BMP 5
DWG Sheet No. 1
Type of structural BMP:
D Retention by harvest and use (HU-1)
D Retention by infiltration basin (INF-1)
□ Retention by bioretention (INF-2)
□ Retention by permeable pavement (INF-3)
Partial retention by biofiltration with partial retention (PR-1)
Kl Biofiltration (BF-1)
□ 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
□ Other (describe in discussion section below)
Purpose:
~ Pollutant control only
D Hydromodification control only
□ Combined pollutant control and hydromodification control
D Pre-treatment/forebay for another structural BMP
D Other (describe in discussion section below)
Discussion (as needed):
Drainage from adjacent roof area will be collected and treated in this basin. Once the
basin is filled , the rainwater is piped to a pump vault then pumped to a relocated drain
inlet in Roosevelt Street. The basin is lined to prevent infiltration of water next to the
building foundation and has a perforated underdrain. A flow restrictor will be used to meet
detention and peak flow reduction requirements. See the included basin detail 1 for
additional information. See the included basin detail 1 for additional information.
The five biofiltration basins are sized to accomodate the 100 year peak flow increase from
the site . See the drainage study for details.
MIN 8" FROM WATER SURFACE TO BOTTOM PLATE
PROPOSED BUILDING -:a~i~~?;~~~;-c-~;,;:-~~~~l; 3. 6 7'
6" STORMWA TER PONDING -' ~.--i
18" ENGINffRED SOIL -__:_:_~~~~t~~ ............ .....,,.,..,
26" OF 3/4" GRAVEL ----~l ~_::----t~~~
LOW FLOW PUMP IN 6" PVC CLEANOUT
40 MIL IMPERMEABLE LINER PER SOILS £NGIN££R
6" PERFORATED SUBDRAIN LAID FLAT
CONNECTED TO STORM DR,.IN
RETAINING WALL
rs PER PLAN
BIOFIL TRA noN BASIN DETAIL 1
N. T.S.
CMU WALL
DOWNSPOUT TO BASIN WHERE
APPLICABLE. INSTALL SPLASH
GUARDS AS NECESSARY
PROPOSED BUILDING
6" PVC FROM DOWNSPOUTS
THROUGH BASIN WALL
12" SQUARE DRAIN INLET
TG PER PLAN
40 MIL IMPERMEABLE LINER PER SOILS ENGINffR 6" PERFORATED SUBDRAIN LAID FLAT
CONNECTED TO STORM DRAIN
BIOFIL TRA noN BASIN DETAIL
N. T. s.
2
CONCRETE DRIVEWAY
CONCRETE DIVIDER STRIP
PERMEABLE PAVEMENT DRIVEWAY
%~~~~
: ~ ~ 1" -2" LEVELING BED
4" CHOKER COURSE
12" OF J/4" GRAVEL
NOT£: PAVEMENT SECTTON MAY VARY DU[ TO SOILS [NGINffR'S
RECOMMENDA TTONS AND 'R' TEST VALUES IN TH£ FIELD
PERMEABLE DRIVEWAY SECnON
N. T.S.
CONCRETE DIVIDER STRIP
ADJACENT GRAD
-~
PERMEABLE WALKWAY
CONCRETE DIVIDER STRIP
ADJACENT GRAD£
1" LEVELING BED
4" OF J/4" GRAVEL
PERMEABLE WALKWAY SECnON
N. T. s.
I I I : ---
i
I
' !
I
i I
I
--!
I i
I i
i
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I '
Attachment
Sequence
Attachment 1 a
Attachment 1 b
Attachment 1 c
Attachment 1 d
.ATTACHMENT 1
BACKUPFORPDPPOLLUTANTCONTROLBMPS
This is the cover sheet for Attachment 1.
Check which Items are Included behind this cover sheet:
Contents Checklist
OMA Exhibit (Required) @Included
See OMA Exhibit Checklist on the
back of this Attachment cover sheet.
(24"x36" Exhibit typically required)
Tabular Summary of DMAs Showing Ii Included on OMA Exhibit in
OMA ID matching OMA Exhibit, OMA Attachment 1 a
Area, and OMA Type (Required)* □ Included as Attachment 1 b,
separate from OMA Exhibit
*Provide table in this Attachment OR
on OMA Exhibit in Attachment 1 a
Form 1-7, Harvest and Use Feasibility □ Included
Screening Checklist (Required unless □ Not included because the entire
the entire project will use infiltration project will use infiltration BMPs
BMPs)
X Included in attachment 1 e
Refer to Appendix 8.3-1 of the BMP
Design Manual to complete Form 1-7.
Form 1-8, Categorization of Infiltration IJ!l Included
Feasibility Condition (Required unless D Not included because the entire
the project will use harvest and use project will use harvest and use
BMPs) BMPs
Refer to Appendices C and D of the
BMP Design Manual to complete
Form 1-8.
Attachment 1e Pollutant Control BMP Design ~ Included
Worksheets / Calculations (Required)
Refer to Appendices B and E of the
BMP Design Manual for structural
pollutant control BMP design
guidelines
Use this checklist to ensure the required information has been included on the OMA
Exhibit:
The OMA Exhibit must identify:
D Underlying hydrologic soil group
□ Approximate depth to groundwater
D Existing natural hydrologic features (watercourses, seeps, springs, wetlands)
□ Critical coarse sediment yield areas to be protected (if present)
D Existing topography and impervious areas
□ 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
D Drainage management area (OMA) boundaries, OMA ID numbers, and OMA areas (square
footage or acreage), and OMA type (i.e., drains to BMP, self-retaining, or self-mitigating)
D Structural BMPs (identify location and type of BMP)
' ! ATTACHMENT 1d
Form 1-8 Categorization of Infiltration Feasibility Condition
--
' '
I
~: :~: I t, ,1,.,-f ., /• -.::-~ ,"'1'1• •:•., ,):-." .'° .,. -. ,.. ~--•; ,~ •~
• • ··categorization of Infiltration Feasibility:(;:ondiiion ,· Form I-8 ·~ . ' . ·~ . . ,, . .. ...
Part 1 -Full Infiltration Feasibility Screening: Criteria
Would infiltration of the full design volume be feasible from a physical perspective without any undesirable
consequences that cannot be reasonably mitigated?
Criteria Screening Question
Is the estimated reliable infiltration rate below proposed
facility locations greater than 0.5 inches per hour? The response
to this Screening Question shall be based on a comprehensive
evaluation of the factors presented in Appendix C.2 and Appendix
D.
Provide basis:
Yes No
X
We performed 2 Aardvark Permeameter tests at the site within the Old Paralic Deposits within the low end of the site
where storm water devices wi ll likely be installed. The following presents the results of our field infiltration tests:
P-1 at 2 feet: 0.008 inches/hour (0.004 inches/hour with FOS=2)
P-2 at 2 feet: 0.183 inches/hour (0.092 inches/hour with FOS=2)
These tests result in an average of 0.096 inches/hour (0.048 inches/hour with an applied factor of safety of 2).
Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide narrative
discussion of study/ data source applicability.
2
Can infiltration greater than 0.5 inches per hour be allowed
without increasing risk of geotechnical hazards ( slope stability,
groundwater mounding, utilities, or other factors) that cannot
be mitigated to an acceptable level? The response to this
Screening Question shall be based on a comprehensive evaluation of
the factors presented in Appendix C.2.
Provide basis:
Geologic hazards do not exist at the site that would preclude infiltration.
X
Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide narrative
discussion of study/ data source applicability.
Project No. G2245-52-0 I -C-7 -May3,2019
Criteria
3
Provide basis:
Screening Question
Can infiltration greater than 0.5 inches per hour be allowed
without increasing risk of groundwater contamination (shallow
water table, storm water pollutants or other factors) that cannot
be mitigated to an acceptable level? The response to this
Screening Question shall be based on a comprehensive evaluation of
the factors presented in Appendix C.3.
Yes No
X
We encountered groundwater during the site investigation at depths ranging from 7½ and 11 ½ feet below the existing
grade. Therefore, infiltration should be considered infeasible at the site
Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide narrative
discussion of study/data so urce applicability.
4
Provide basis:
Can infiltration greater than 0.5 inches per hour be allowed
without causing potential water balance issues such as change
of seasonality of ephemeral streams or increased discharge of
contaminated groundwater to surface waters? The response to
this Screening Question shall be based on a comprehensive
evaluation of the factors presented in Appendix C.3.
X
We do not expect infiltration will cause water balance issues such as seasonality of ephemeral streams or increased
discharge of contaminated groundwater to surface waters.
Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide narrative
discussion of study/ data source applicability.
Part 1
Result*
If all answers to rows 1 -4 are ''Yes" a full infiltration design is potentially feasible.
The feasibility screening category is Full Infiltration
If any answer from row 1-4 is "No", infiltration may be possible to some extent but
would not generally be feasible or desirable to achieve a "full infiltration" design.
Proceed to Part 2
No Full
lnfi ltration
*To be completed using gathered site information and best professional judgment considering the definition of l\.1EP in the
MS4 Permit. Additional testing and/ or studies may be required by the City to substantiate findings.
Project No. 02245-52-0 I -C-8 -May 3, 20 19
I
_/
I~ \ , • •· • t ., " ' ,I._ ., • r •••.,•(, "" , • . ~ ~ • • .,, ' 'V • \
Worksheet CA'...1 Page 3 of 4 • .. 1•'
Part 2 -Partial Infiltration vs. No Infiltration Feasibility ScreeningCriteria
Would infiltration of water in any appreciable amount be physically feasible without any negative
consequences that cannot be reasonably mitigated?
Criteria
5
Provide basis:
Screening Question
Do soil and geologic conditions allow for infiltration in any
appreciable rate or volume? The response to this Screening
Question shall be based on a comprehensive evaluation of the
factors presented in Appendix C.2 and Appendix D.
Yes No
X
We performed 2 Aardvark Permeameter tests at the site within the Old Paralic Deposits within the low end of the site
where storm water devices will likely be installed. The following presents the results of our field infiltration tests:
P-1 at 2 feet: 0.008 inches/hour (0.004 inches/hour with FOS=2)
P-2 at 2 feet: 0.183 inches/hour (0.092 inches/hour with FOS=2)
These tests result in an average of0.096 inches/hour (0.048 inches/hour with an applied factor of safety of2). The
average infiltration rate at the site is less than 0.05 inches/hour, therefore, partial infiltration should be considered
infeasible.
Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide narrative
discussion of study/ data source applicability and why it was not feasible to mitigate low infiltration rates.
6
Provide basis:
Can Infiltration in any appreciable quantity be allowed
without increasing risk of geotechnical hazards (slope
stability, groundwater mounding, utilities, or other factors)
that cannot be mitigated to an acceptable level? The response
to this Screening Question shall be based on a comprehensive
evaluation of the factors presented in Appendix C.2.
Geologic hazards do not exist at the site that wo uld preclude infiltration.
X
Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide narrative
discussion of study/data source applicability and why it was not feasible to mitigate low infiltration rates.
Project No. G2245-52-0 I -C-9 -May 3, 20 19
..,. --r , V ,. • ' ..-::,i• • .,., -,.
'.. • Worksheet C.4-1 Page 4 of 4 •
Criteria
7
Provide basis:
Screening Question
Can Infiltration in any appreciable quantity be allowed
without posing significant risk for groundwater related
concerns (shallow water table, storm water pollutants or other
factors)? The response to this Screening Question shall be based
on a comprehensive evaluation of the factors presented in
Appendix C.3 .
Yes No
X
We encountered groundwater during the site investigation at depths ranging from 7½ and 11 ½ feet below the existing
grade. Therefore, infiltration should be considered infeasible at the site.
Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide narrative
discussion of study/ data source applicability and why it was not feasible to mitigate low infiltration rates.
8
Provide basis:
Can infiltration be allowed without violating downstream
water rights? The response to this Screening Question shall be
based on a comprehensive evaluation of the factors presented in
Appendix C.3.
X
We did not provide a study regarding water rights. However, these rights are not typical in the San Diego County area.
Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide narrative
discussion of study/ data source applicability and why it was not feasible to mitigate low infiltration rates.
Part 2
Result*
If all answers from row 1-4 are yes then partial infiltration design is potentially feasible.
The feasibility screening category is Partial Infiltration.
If any answer from row 5-8 is no, then infiltration of any volume is considered to be
infeasible within the drainage area. The feasibility screening category is No Infiltration.
No Infiltration
*To be completed using gathered site information and best professional judgment considering the definition of MEP in the
MS4 Permit. Additional testing and/ or studies may be required by the City to substantiate findings.
Project No. G2245-52-0 I -C-10 -May 3, 2019
I
Appendix B: Storm Water Pollutant Control Hydrologic Calculations and Sizing Methods
Worksheet B.2-1. DCV BMPl
1 85th percentile 24-hr storm depth from Figure B.1 -1 d= 0.58 inches
2 Area tributary to BMP (s) A= 2,708 square-£ eet
Area weighted runoff factor (es timate using Appendix
0.90 3 B.1.1 and B.2.1) C= unitless
4 Tree wells volume reduction TCV= cubic-feet
5 Rain barrels volume reduction RCV= cubic-feet
Calculate DCV =
6 (C x d x A/ 12) -TCV -RCV DCV= 118 cubic-feet
B-10 February 2016
Appendix B: Storm Water Pollutant Control H ydrologic Calculations and Sizing M ethods
Worksheet B.5-1: Simple Sizing Method for Biofiltration BMPs BMPl
...... ·-··· --·••r.rliTiTi•liTIIIII i1Ti1il , • .,... , •• :J~•~-•• , .. ,.,.
1 Remaining DCV after implementing retention BMPs 118 cubic-feet
Partial Retention
2 Infiltration rate from Form I-9 if partial infiltration is feasible in/hr.
3 Allowable drawdown time for aggregate storage below the underdrain 36 hours
4 Depth of runoff that can be infiltrated [Line 2 x Line 3) inches
5 Aggregate pore space 0.40 in/in
6 Required depth of gravel below the underdrain [Line 4/ Line 5) 0 inches
7 Assumed surface area of the biofiltration BMP 89 sq-ft
8 Media retained pore storage 0.1 in/in
9 Volume retained by BMP [[Line 4 + (Line 12 x Line 8))/12) x Line 7 13 cubic-feet
10 DCV that requires biofiltration [Line 1 -Line 9) 105 cubic-feet
BMP Parameters
11 Surface Ponding [6 inch minimum, 12 inch maximum] 6 inches
12 Media Thickness [18 inches minimum], also add mulch layer thickness to 18 inches this line for sizing calculations
13 Aggregate Storage above underdrain invert (12 inches typical) -use 0 26 inches inches for sizing if the aggregate is not over the entire bottom surface area
14 Media available pore space 0.2 in/in
15 Media filtration rate to be used for sizing (5 in/hr. with no outlet control; 5 in/hr. if the filtration is controlled by the outlet, use the outlet controlled rate)
Baseline Calculations
16 Allowable Routing Time for sizing 6 hours
17 Depth filtered during storm [ Line 15 x Line 16) 30 inches
18 Depth of Detention Storage 18.8 inches [Line 11 + (Line 12 x Line 14) + (Line 13 x Line 5))
19 Total Depth Treated [Line 17 + Line 18) 48.8 inches
Option 1-Biofilter 1.5 times the DCV
20 Required biofiltered volume [1.5 x Line 10) 158 cubic-feet
21 Required Footprint [Line 20 / Line 19) x 12 39 sq-ft
Option 2 -Store 0.75 of remaining DCV in pores and ponding
22 Required Storage (surface+ pores) Volume [0.75 x Line 10) 79 cubic-feet
23 Required Footprint [Line 22 / Line 18) x 12 so sq-ft
Footorint of the BMP
24 Area draining to the BMP 2,708 sq-ft
25 Adjusted Runoff Factor for drainage area (Refer to Appendix B.1 and B.2) 0.90
26 Minimum BMP Footprint [Line 24 x Line 25 x 0.03) 73 sq-ft
27 Footprint of the BMP = Maximum(Minimum(Line 21, Line 23), Line 26) 73 sq-ft
N ote: Line 7 is used to estimate the amount of volume retained by the BMP. Update assumed surface area in Line 7 until
its equivalent to the required biofiltration footprint (either Line 21 or Line 23)
B-26 February 2016
Appendix B: Storm Water Pollutant Control H ydrologic Calculations and Sizing Methods
Worksheet B.2-1. DCV BMP2
, . ,. -.
' . _-.. 1?.e~ign· <::~~ture V olui:n:e . Worksheet B.:2.1 • , : _.,. ·_ .. ,. ,, ..
1 85th percentile 24-hr storm depth from Figure Rl-1 d= 0.58 inches
2 Area tributary to BMP (s) A= 1,146 square-£ eet
Area weighted runoff factor (estimate using ppendix
0.90 3 B.1.1 and B.2.1) C= unitless
4 Tree wells volume reduction TCV= cubic-feet
5 Rain barrels volume reduction RCV= cubic-feet
Calculate DCV =
6 (C x d x A/ 12) -TCV -RCV DCV= so cubic-feet
B-10 February 2016
Appendix B: Storm Water Pollutant Control H ydrologic Calculations and Sizing Methods
Worksheet B.5-1: Simple Sizing Method for Biofiltration BMPs BMP2
ll!!llIIllll"-<VAII• :'.1111r;;thrn1an1,a itl'i1H■■ r. ■■r , •• i'l~'JI ffil'il■
1 Remaining DCV after implementing retention BMPs 50 cubic-feet
Partial Retention
2 Infiltration rate from Form I-9 if partial infiltration is feasible in/hr.
3 Allowable drawdown time for aggregate storage below the underdrain 36 hours
4 Depth of runoff that can be infiltrated [Line 2 x Line 3] inches
5 Aggregate pore space 0.40 in/in
6 Required depth of gravel below the underdrain [Line 4/ Line 5] 0 inches
7 Assumed surface area of the biofiltration BMP 50 sq-ft
8 Media retained pore storage 0.1 in/in
9 Volume retained by BMP [[Line 4 + (Line 12 x Line 8)]/12] x Line 7 8 cubic-feet
10 DCV that requires biofiltration [Line 1 -Line 9] 42 cubic-feet
BMP Parameters
11 Surface Ponding [6 inch minimum, 12 inch maximum] 6 inches
12 Media Thickness [18 inches minimum], also add mulch layer thickness to 18 inches this line for sizing calculations
13 Aggregate Storage above underdrain invert (12 inches typical) -use 0 26 inches inches for sizing if the aggregate is not over the entire bottom surface area
14 Media available pore space 0.2 in/in
15 Media filtration rate to be used for sizing (5 in/hr. with no outlet control; 5 in/hr. if the filtration is controlled by the outlet, use the outlet controlled rate)
Baseline Calculations
16 Allowable Routing Time for sizing 6 hours
17 Depth filtered during storm [ Line 15 x Line 16] 30 inches
18 Depth of Detention Storage 18.8 inches [Line 11 + (Line 12 x Line 14) + (Line 13 x Line 5)]
19 Total Depth Treated [Line 17 + Line 18] 48.8 inches
Option 1 -Biofilter 1.5 times the DCV
20 Required biofiltered volume [1.5 x Line 10] 63 cubic-feet
21 Required Footprint [Line 20/ Line 19] x 12 15 sq-ft
Option 2 -Store 0.75 of remaining DCV in pores and ponding
22 Required Storage (surface+ pores) Volume [0.75 x Line 10] 32 cubic-feet
23 Required Footprint [Line 22 / Line 18] x 12 20 sq-ft
Footprint of the BMP
24 Area draining to the BMP 1,146 sq-ft
25 Adjusted Runoff Factor for drainage area (Refer to Appendix B.1 and B.2) 0.90
26 Minimum BMP Footprint [Line 24 x Line 25 x 0.03] 31 sq-ft
27 Footprint of the BMP = Maximum(Minimum(Line 21, Line 23), Line 26) 31 sq-ft
Note: Line 7 is used to estimate the amount of volume retained by the BMP. Update assumed surface area in Line 7 until
its equivalent to the required biofiltration footprint (either Line 21 or Line 23)
B-26 February 2016
Appendix B: Storm Water Pollutant Control H ydrologic Calculations and Sizing Methods
Worksheet B.2-1. DCV BMP3
Design Capture Volume Worksheet B-2.1
1 85th percentile 24-hr storm depth from Figure B.1-1 d= 0.58 inches
2 Area tributary to BMP (s) A= 2,660 square-feet
Area weighted runoff factor (estimate using Appendix
0.90 3 B.1.1 and B.2.1) C= unitless
4 Tree wells volume reduction TCV= cubic-feet
5 Rain barrels volume reduction RCV= cubic-feet
Calculate DCV =
6 (C x d x A/12) -TCV -RCV DCV= 116 cubic-feet
B-10 February 2016
Appendix B: Storm Water Pollutant Control H ydrologic Calculations and Sizing Methods
Worksheet B.5-1: Simple Sizing Method for Biofiltration BMPs BMP3
~ ,n.-..'l.-A1■L.T.1,.. " .r11•11Ti1n11r.11u11• :11lT.1I ..
Remaining DCV after implementing retention BMPs 116 cubic-feet
Partial Retention
2 Infiltration rate from Form I-9 if partial infiltration is feasible in/hr.
3 Allowable drawdown time for aggregate storage below the underdrain 36 hours
4 Depth of runoff that can be infiltrated !Line 2 x Line 3] inches
5 Aggregate pore space 0.40 in/in
6 Required depth of gravel below the underdrain [Line 4/ Line 5] 0 inches
7 Assumed surface area of the biofiltration BMP 82 sq-ft
8 Media retained pore storage 0.1 in/in
9 Volume retained by BMP [!Line 4 + (Line 12 x Line 8))/12] x Line 7 12 cubic-feet
10 DCV that requires biofiltration !Line 1 -Line 9] 104 cubic-feet
BMP Parameters
11 Surface Ponding [6 inch minimum, 12 inch maximum] 6 inches
12 Media Thickness [18 inches minimum], also add mulch layer thickness to 18 inches this line for sizing calculations
13 Aggregate Storage above underdrain invert (12 inches typical) - use 0 26 inches inches for sizing if the aggregate is not over the entire bottom surface area
14 Media available pore space 0.2 in/in
15 Media filtration rate to be used for sizing (5 in/hr. with no outlet control; 5 in/hr. if the filtration is controlled by the outlet, use the outlet controlled rate)
Baseline Calculations
16 Allowable Routing Time for sizing 6 hours
17 Depth filtered during storm [ Line 15 x Line 16] 30 inches
18 Depth of D etention torage 18.8 inches !Line 11 + (Line 12 x Line 14) + (Line 13 x Line 5)]
19 Total Depth Treated !Line 17 + Line 18] 48.8 inches
Option 1-Biofilter 1.5 times the DCV
20 Required biofiltered volume [1.5 x Line 10] 156 cubic-feet
21 Required Footprint jLine 20/ Line 19] x 12 38 sq-ft
Option 2 -Store 0. 75 of remaini~ DCV in pores and pondi~
22 Required Storage (surface+ pores) Volume [0.75 x Line 10] 78 cubic-feet
23 Required Footprint !Line 22/ Line 18] x 12 so sq-ft
Footprint of the BMP
24 Area draining to the BMP 2,660 sq-ft
25 Adjusted Runoff Factor fo r drainage area (Refer to Appendix B.1 and B.2) 0.90
26 Minimum BMP Footprint !Line 24 x Line 25 x 0.03] 72 sq-ft
27 Footprint of the BMP = Maximum(Minimum(Line 21, Line 23), Line 26) 72 sq-ft
Note: Line 7 is used to estimate the amount of volume retained by the BMP. Update assumed surface area in Line 7 until
its equivalent to the required biofiltration footprint (either Line 21 or Line 23)
B-26 February 2016
Appendix B: Storm Water Pollutant Control Hydrologic Calculations and Sizing Methods
Worksheet B.2-1. DCV BMP4
Design Capture Volume Worksheet B-2.1
1 85th percentile 24-hr storm depth from Figure B.1-1 d= 0.58 inches
2 Area tributary to BMP (s) A= 2,764 square-feet
Area weighted runoff factor (estimate using Appendix
0.90 3 B.1.1 and B.2.1) C= unitless
4 Tree wells volume reduction TCV= cubic-feet
5 Rain barrels volume reduction RCV= cubic-feet
Calculate DCV =
6 (C x d x A/ 12) -TCV -RCV DCV= 120 cubic-feet
B-10 February 2016
Appendix B: Storm Water Pollutant Control H ydrologic Calculations and Sizing Methods
Worksheet B.5-1: Simple Sizing Method for Biofiltration BMPs BMP4
~
" ■fflilliffflih1,...,1, ,..,111s1l~·i■
er implementing retention BMPs 120 cubic-feet
Partial Retention
2 Infiltration rate from Form I-9 if partial infiltration is feasible in/hr.
3 Allowable drawdown time for aggregate storage below the underdrain 36 hours
4 Depth of runoff that can be infiltrated [Line 2 x Line 3] inches
5 Aggregate pore space 0.40 in/in
6 Required depth of gravel below the underdrain [Line 4 / Line 5] 0 inches
7 Assumed surface area of the biofiltration BMP 86 sq-ft
8 Media retained pore storage 0.1 in/in
9 Volume retained by BMP [[Line 4 + (Line 12 x Line 8)]/12] x Line 7 13 cubic-feet
10 D CV that requires biofiltration [Line 1 -Line 9] 107 cubic-feet
BMP Parameters
11 Surface Ponding [6 inch minimum, 12 inch maximum] 6 inches
12 Media Thickness [18 inches minimum], also add mulch layer thickness to 18 inches this lin e for sizing calculations
13 Aggregate Storage above underdrain invert (12 inches typical) -use 0 26 inches inches for sizing if the aggregate is not over the entire bottom surface area
14 Media available pore space 0.2 in/in
15 Media filtration rate to be used for sizing (5 in/hr. with no outlet control; 5 in/hr. if the filtration is controlled by the outlet, use the outlet controlled rate)
Baseline Calculations
16 Allowable Routing Time for sizing 6 hours
17 D epth filtered during storm [ Line 15 x Line 16] 30 inches
18 Depth of D etention Storage 18.8 inches [Line 11 + (Line 12 x Line 14) + (Line 13 x Line 5)]
19 Total Depth Treated [Line 17 + Line 18] 48.8 inches
Option 1 -Biofilter 1.5 times the DCV
20 Required biofiltered volume [1.5 x Line 10] 161 cubic-feet
21 Required Footprint [Line 20/ Line 19] x 12 39 sq-ft
Option 2 -Store 0.75 of remaining DCV in pores and ponding
22 Required Storage (surface+ pores) Volume [0.75 x Line 10] 80 cubic-feet
23 Required Footprint [Line 22/ Line 18] x 12 51 sq-ft
Footprint of the BMP
24 Area draining to the BMP 2,764 sq-ft
25 Adjusted Runoff Factor for drainage area (Refer to Appendix B.1 and B.2) 0.90
26 Minimum BMP Footprint [Line 24 x Line 25 x 0.03] 75 sq-ft
27 Footprint of the BMP = Maximum(Minimum(Line 21, Line 23), Line 26) 75 sq-ft
Note: Line 7 is used to estimate the amount of volume retained by the BMP. Update assumed surface area in Line 7 until
its equivalent to the required biofiltration footprint (either Line 21 or Line 23)
B-26 February 2016
Appendix B: Storm Water Pollutant Control Hydrologic Calculations and Sizing Methods
Worksheet B.2-1. DCV BMPS
Design Capture Volume Worksheet B-2.1
1 85th percentile 24-hr storm depth from Figure B.1-1 d= 0.58 inches
2 Area tributary to BMP (s) A= 2,798 square-feet
Area weighted runoff factor (estimate using Appendix
0.90 3 B.1.1 and B.2.1) C= unitless
4 Tree wells volume reduction TCV= cubic-feet
5 Rain barrels volume reduction RCV= cubic-feet
Calculate DCV =
6 (C x d x A/ 12) -TCV -RCV DCV= 122 cubic-feet
B-10 February 2016
Appendix B: Storm Water Pollutant Control H ydrologic Calculations and Sizing Methods
Worksheet B.5-1: Simple Sizing Method for Biofiltration BMPs BMPS
a;Jlij]'alr:.a...~rA■■a. . 'i■m.1111 :iNil•
1 Remaining DCV after implementing retention BMPs 122 cubic-feet
Partial Retention
2 Infiltration rate from Form I-9 if partial infiltration is feasible in/hr.
3 Allowable drawdown time for aggregate storage below the underdrain 36 hours
4 Depth of runoff that can be infiltrated (Line 2 x Line 3) inches
5 Aggregate pore space 0.40 in/in
6 Required depth of gravel below the underdrain [Line 4/ Line 5) 0 inches
7 Assumed surface area of the biofiltration BMP 89 sq-ft
8 Media retained pore storage 0.1 in/in
9 Volume retained by BMP [(Line 4 + (Line 12 x Line 8))/12) x Line 7 13 cubic-feet
10 DCV that requires biofiltration [Line 1 -Line 9) 109 cubic-feet
BMP Parameters
11 Surface Ponding [6 inch minimum, 12 inch maximum) 6 inches
12 Media Thickness [18 inches minimum), also add mulch layer thickness to 18 inches this line for sizing calculations
13 Aggregate Storage above underdrain invert (12 inches typical) -use 0 26 inches inches for sizing if the aggregate is not over the entire bottom surface area
14 Media available pore space 0.2 in/in
15 Media filtration rate to be used for sizing (5 in/hr. with no outlet control; 5 in/hr. if the filtration is controlled by the outlet, use the outlet controlled rate)
Baseline Calculations
16 Allowable Routing Time for sizing 6 hours
17 Depth filtered during storm [ Line 15 x Line 16) 30 inches
18 Depth of Detention Storage 18.8 inches [Line 11 + (Line 12 x Line 14) + (Line 13 x Line 5))
19 Total Depth Treated [Line 17 + Line 18) 48.8 inches
Option 1 -Biofilter 1.5 times the DCV
20 Required biofiltered volume [1.5 x Line 10) 164 cubic-feet
21 Required Footprint [Line 20/ Line 19) x 12 40 sq-ft
Option 2 -Store 0. 75 of remaining DCV in pores and pondint?
22 Required Storage (s urface+ pores) Volume [0.75 x Line 10) 82 cubic-feet
23 Required Footprint [Line 22/ Line 18) x 12 52 sq-ft
Footprint of the BMP
24 Area draining to the BMP 2,798 sq-ft
25 Adjusted Runoff Factor for drainage area (Refer to Appendix B.1 and B.2) 0.90
26 Minimum BMP Footprint [Line 24 x Line 25 x 0.03) 76 sq-ft
27 Footprint of the BMP = Maximum(Minimum(Line 21 , Line 23), Line 26) 76 sq-ft
Note: Line 7 is used to estimate the amount of volume retained by the BMP. Update assumed surface area in Line 7 until
its equivalent to the required biofiltration footprint (either Linc 21 or Line 23)
B-26 February 2016
Automated Worksheet B.3-1: Pro'ect-Scale BMP Feasibili
Category
Capture & Use
Inputs
Infiltration
Inputs
# -1
2
3
4
5
6
7
8
9 ---Calculations -----Result -
Worksheet B.3-1 General N otes:
Description
Design Capture Volume for E ntire Project Site
Proposed Development Type
Number of Residents or Employees at Proposed Developmen
Total Planted Area within Development
Water Use Category for Proposed Planted Areas
ls Average Site Design Infiltration Rate ~0.500 Inches per Hour?
Is Average Site Design Infiltration Rate ~0.010 Inches per I-lour?
ls Infiltration of the Full DCV Anticipated to Produce Negative Impacts?
ls Infiltration of Any Volume Anticipated to Produce Negative Impacts?
36-Hour Toilet Use Per Resident or E mployee
Subtotal: Anticipated 36 Hour Toilet Use
Anticipated 1 Acre Landscape Use Over 36 I-lours
Subtotal: Anticipated Landscape Use Over 36 Hours
Total Anticipated Use Over 36 I-lours
Total Anticipated Use / Design Capture Volume
Are Full Capture and Use Techniques Feasible for this Project?
Is Full Retention Feasible for this Project?
Is Partial Retention Feasible for this Project?
Feasibility Category
Value Units
------
Residential unitless
40 #
4,046 sq-ft
Moderate unitless
Yes yes /no
No yes/no
Yes yes /no
Yes yes /no
1.86 cubic-feet
75 cubic-feet
196.52 cubic-feet
18 cubic-feet
93 cubic-feet
0.16 cubic-feet
No unitless
No yes /no
No yes /no
5 1, 2, 3, 4, 5
A. Applicants may use this worksheet to determine the types of structural BMPs that are acceptable for implementation at their project site (as
required in Section 5 of the BMPDM). User input should be provided for yellow shaded cells, values for all other cells will be automatically
generated. Projects demonstrating feasibility or potential feasibility via this worksheet are encouraged to incorporate capture and use features
in their project.
B. Negative impacts associated with retention may include geotechnical, groundwater, water balance, or other issues identified by a
geotechnical engineer and substantiated through completion of Form 1-8.
C. Feasibility Category 1: Applicant must implement capture & use, retention, and/or infiltration elements for the entire DCV.
D. Feasibility Category 2: Applicant must implement capture & use elements for the entire DCV.
E. Feasibility Category 3: Applicant must implement retention and/or infiltration elements for all DMAs with Design Infiltration Rates greater
than 0.50 in/hr.
F. Feasibility Category 4: Applicant must implement standard unlined biofiltration BMPs sized at ~3% of the effective impervious tributary
area for all DMAs with Design In filtration Rates of 0.011 to 0.50 in/hr. Applicants may be permitted to implement lined BMPs, reduced size
BMPs, and/or specialized biofiltration BMPs provided additional criteria identified in "Supplemental Retention Criteria fo r Non-Standard
Biofiltration BMPs" are satisfied.
G. Feasibility Category 5: Applicant must implement standard lined biofiltration BMPs sized at ~3% of the effective impervious tributary area
for all DMAs with Design Infiltration Rates of0.010 in/hr or less. Applicants may also be permitted to implement reduced size and/or
specialized biofiltration BMPs provided additional criteria identified in "Supplemental Retention Criteria fo r Non-Standard Biofiltration
BMPs" are satisfied.
I-I. PDPs participating in an offsite alternative compliance program are not held to the feas ibility categories presented herein.
1.3)
Draina re Basin ID or Name BMl'l HMP2 HMP 3 BM1'4 B~II' 5 unit1css
Basin Drains to the Following BMP Type Biofiltration Biofiltration Biofiltratlon Biofiltration Biofiltration unit1ess
85th Percentile 24--hr Storm De th 0.58 0.58 11.58 0.58 11.58
0.048 0.048 0.048 0.048 0.048
-·rsion Ar a (C=O. 90) 2,708 1,146 2,660 2,764 2,798
rsion Ar ·a (C=0.30)
No No No No No
er SD-B (Ci=O. 90)
r SD-B Ci=0.10)
B Soil Serving as Dispersion Area er SD-B (Ci=0.14)
• C Soil Serving as Dispersion Area er SD-B (Ci=0.23)
#
gal
Does BMP O,·crflow to Stormwatcr Features in Downstream Drainage? 0 No No 0 No unit1ess
0 0 0 0 ()
0 0 0 () 0
2,708 1,146 2,660 2,764 2,798
0.90 0.90 0.90 0.90 0.90
Initial Runoff Factor for Dis ersed & Dis crsion Areas 0.00 0.00 0.00 0.(Xl
0.90 0.90 0.90 0.90 0.90
118 so 116 120 122
0 0 0 0 ()
() 0 0 0 ()
n/a n/a n/a n/a n/a
1.00 1.00 1.00 1.00 1.00 ratio
0.90 0.90 0.90 0.90 0.90 unitlcss
Dcsirn Ca 118 so 116 1211 122 cubic-feet
II II 0 0 II cubic-feet
Total Rain Barrel Volume Reduction II 0 0 II () cubic-feet
0.90 0.90 0.90 0.911 0.90 unitlcss
2,437 1,031 2,394 2,488 2,5 18 s -ft
Initial Desi rn Ca turc Volume Retained b I Site Desi II II 0 0 0 cubic-feet
11 8 50 116 120 122 cubic-feet
A. Applicants may use this worksheet to calculate design capture ,·olumcs for up to 10 drainage areas User input must be pro,·ided for yellow shaded cells, values for all other cells will be automatically
generated, errors/notifications will be high Lighted in red and summarized below. Upon completion of this worksheet, proceed to the appropriate BMP Sizing worksheet(s).
I . • I . • • I Lined or Unlined Biofiltration BMPs (Vl.3
Category
BMP Inputs
# -1111 -3
4
5
6
7
8
9 ------Retention -
Calculations ---m --------Biofiltration El
Calculations IIDI -El IIDI IIDI --
Design Infiltration Rate Recommended by Geotechnical Engineer
Effective Tributary Area
Minimum Biofiltration Footprint Sizing Factor
Design Capture Volume Tributary to BMP
Is Biofiltration Basin Impermeably Lined or Unlined?
Provided Biofiltration BMP Surface Area
Provided Surface Ponding Depth
Provided Soil Media Thickness
Provided Depth of Gravel Above Underdrain Invert
Diameter of Underdrain or I lydromod Orifice (Select Smallest)
Provided Depth of Gravel Below the Underdrain
Volume Infiltrated Over 6 I lour Storm
Soil Media Pore Space Available for Retention
Gravel Pore Space Available for Retention
Effective Retention Depth
Calculated Retention Storage Drawdown (Including 6 I lr Storm)
Volume Retained by BMP
Fraction of DCV Retained
Portion of Retention Performance Standard Satisfied
Fraction of DCV Retained (normalized to 36-hr drawdown)
Design Capture Volume Remaining for Biofiltration
Max Hydromod Flow Rate through Underdrain
Max Soil Filtration Rate Allowed by Underdrain Orifice
Soil Media Filtration Rate per Specifications
Soil Media Filtration Rate to be used for Sizin
Depth Biofiltered Over 6 I lour Storm
Soil Media Pore Space Available for Biofiltration
Effective Depth of Biofiltration Storage
Drawdown Time for Surface Ponding
Drawdown Time for Effective Biofiltration De th
Total De th Biofiltered
0 tion 1 -Biofilter 1.50 DCV: Tar et Volume
0 tion 1 -Provided Biofiltration Volume
0 tion 2 -Store 0.75 DCV: Tar et Volume
0 tion 2 -Provided Storage Volume
Portion of Biofiltration Performance Standard Satisfied -Do Site Desi 1 Elements and BMPs Satisfy Annual Retention Re uirements?
Overall Portion of Performance Standard Satisfied
This BMP Overflows to tl1e Following Drainage Basin --Result -Deficit of Effectively Treated Stormwater
WQrk§hi:i:t B,5-1 Gi:ni;r,11 ~foti:§:
0.048
2,437
0.030
118
Lin ed
89
6
18
23
0.50
3
0
0.05
0.00
0.90
120
7
0.06
0.07
0.03
114
0.0130
6.29
5.00
5.00
30.00
0.20
18 80
4
48.80
171
171
86
86
1.00
"-o
1.00
0
1,031 2,394
0.030 0.030
50 116
Lined Lined
50 82
6 6
18 18
23 23
0.50 0.50
3 3
0 0
0.05 0.05
0.00 0.00
0.90 0.90
120 120
4 6
0.08 0.05
0.10 0.06
0.05 0.03
48 113
0.0130 0.0130
11 .20 6.83
5.00 5.00
5.00 5.00
30.00 30.00
0.20 0.20
18.80 18.80
4 4
48.80 48.80
72 170
72 170
36 85
36 85
1.00 1.00
() 0
1.00 1.00
0 0
0.048
2,488 2,518 sq-ft
0.030 0.030 ratio
120 122 cubic-feet
Lined Lined unitless
86 89 sq-ft
6 6 inches
18 18 inches
23 23 inches
0.50 0.50 inches
3 3 inches
0 0 cubic-feet
0.05 0.05 unitless
0.00 0.00 unitless
0.90 0.90 inches
120 120 hours
6 7 cubic-feet
0.05 0.05 ratio
0.06 0.06 ratio
0.03 0.03 ratio
11 6 11 8 cubic-feet
0.0130 0.0130 CFS
6.51 6.29 in/hr
5.00 5.00 in/hr
5.00 5.00 in/hr
30.00 30.00 inches
0.20 0.20 unitless
18.80 18.80 inches
hours
4 4 hours
48.80 48.80 inches
174 177 cubic-feet
174 177 cubic-feet
87 89 cubic-feet
87 89 cubic-feet
1.00 1.00 ratio
() es/no
1.00 1.00 ratio
unitless
0 0 cubic-feet
A. Applicants may use this worksheet to size Lined or Unlined Biofiltration BMPs (BF-1, PR-1) for up to 10 basins. User input must be provided for yellow shaded cells, values for blue cells are
automatically populated based on user inputs from previous worksheets, values for all other cells will be automatically generated, errors/notifications will be highlighted in red/orange and
summarized below. BMPs fully satisfying the pollutant control performance standards will have a deficit treated volume of zero and be highlighted in green .
of Sto rmwater Pollutant Control Calculations (Vl.3)
85th Percentile Storm Depth 0.58 0.58 0.58 0.58 0.58 inches
Design Infiltration Rate Recommended by Gcotechnical 0048 0.048 0.048 0.048 0.048 in/hr En6>111eer
Total Tributary Arca 2,708 1,146 2,660 2,764 2,798 sq-ft
85th Percentile Storm Volume (Rainfall Volume) 131 55 129 134 135 cubic-feet
Initial Weighted Runoff Factor 0.90 0.90 0.90 0.90 0.90 unicless
Initial Design Capture Volume 118 50 116 120 122 cubic-feet
Dispersion r\rca Reductions 0 0 0 0 0 cubic-feet
Tree Well and Rain Barrel Reductions 0 0 0 0 0 cubic-feet
Effective Area Tributary to BMP 2,437 1,031 2,394 2,488 2,518 square feet
Final Design Capture Volume Tributary to BMP 118 50 11 6 120 122 cubic-feet
Basin Drains to the Following BMP Type Bio filtration Bio filtration Bio filtration Biofiltration Biofiltration unitlcss
Volume Retained by BMP 4 3 3 4 4 cubic-feet (normalized to 36 hour drawdown)
Total Fraction of Initial DCV Retained within DIVlA 0.03 0.06 0.03 0.03 0.03 fraction
Percent of Average Annual Runoff Retention Provided -1.6° 0 9.1°0 4.6° 0 4.6°0 4.61l0 %
Percent of Average Annual Runoff Retention Required 14.5% 14.5% 14.5% 14.5% 14.5% %
Percent of Pollution Control Standard Satisfied 100.0% 100.0% 100.0% 100.0% 100.0% %
Discharges to Secondary Treatment in Drainage Basin unitless
Impervious Surface Area Still Requiring Treatment 0 0 0 0 0 square feet
Impervious Surfaces Directed to Downstream Dispersion square feet Arca
Impervious Surfaces Not Directed to Downstream square feet Dispersion Area
Deficit of Effectively Treated Stormwater 0 0 0 0 0 cubic-feet
Summary Notes:
All fields in this summary worksheet are populated based on previous user inputs. 1 f applicable, drainage basin elements that require revisions and/ or supplemental
information outside the scope of these worksheets arc highlighted in orange and summa.irzed in the red text below. If all drainage basins achieve full compliance without a
• 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 Contents Checklist
Sequence
Attachment 2a Hydromodification Management □ Included
Exhibit (Required)
See Hydromodification Management
Exhibit Checklist on the back of this
Attachment cover sheet.
Attachment 2b Management of Critical Coarse □ Exhibit showing project drainage
Sediment Yield Areas (WMAA Exhibit boundaries marked on WMAA
is required, additional analyses are Critical Coarse Sediment Yield
optional) Area Map (Required)
See Section 6.2 of the BMP Design Optional analyses for Critical Coarse
Manual. Sediment Yield Area Determination
□ 6.2.1 Verification of Geomorphic
Landscape Units Onsite
□ 6.2.2 Downstream Systems
Sensitivity to Coarse Sediment
□ 6.2.3 Optional Additional Analysis
of Potential Critical Coarse
Sediment Yield Areas Onsite
Attachment 2c Geomorphic Assessment of Receiving □ Not performed
Channels (Optional) □ Included
See Section 6.3.4 of the BMP Design
Manual.
Attachment 2d Flow Control Facility Design and □ Included
Structural BMP Drawdown
Calculations (Required)
See Chapter 6 and Appendix G of the
BMP Desion Manual
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)
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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:
1)(1 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:
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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)
D 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
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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
The structural BMP Maintenance Plan is in accordance with Category 1 requirements with
minimal maintenance responsibilities on a single family residential project. The property owner
is responsible to ensure inspection, operation, and maintenance of the structural BMP.
Inspection of the biofiltration basins will be performed annually prior to the start of the rainy
season. The biofiltration basins are accessible to the property owner. The inspection will
include measuring the ground elevation is 6" below the opening or riser top elevation and
adjusting the grade as necessary to provide 6" of surface ponding. The property owner will
provide annual self-certification that inspection and maintenance has been performed, provide
details of the inspection results and maintenance activities, and confirm or update the contact
information for the party responsible to ensure inspection and maintenance is performed.
Typical Maintenance lndicator(s) for Maintenance Actions
Vegetated BMPs
Accumulation of sediment, litter, or Remove & properly dispose of
debris accumulated materials, without damage to
the vegetation
Poor vegetation establishment Reseed, replant or re-establish vegetation
Overgrown vegetation Mow or trim as appropriate
Erosion due to concentrated irrigation Repair and adjust the irrigation system
flow
Standing water in biofiltration areas Make appropriate corrective measures
such as repairing underdrain pump,
removing obstructions of debris or
invasive vegetation, clearing
underdrains, or repairing/replacing
clogged or compacted soils
Obstructed inlet or outlet structure Clear obstructions
Damage to structural components such Repair or replace as applicable
walls or outlet structures
ATTACHMENT 4
City standard Single Sheet BMP (SSBMP) Exhibit
[Use the City's standard Single Sheet BMP Plan.]