HomeMy WebLinkAboutSDP 2020-0005; CHILDREN'S PARADISE; STORM WATER QUALITY MANAGEMENT PLAN; 2020-05-26C
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CITY OF CARLSBAD
PRIORITY DEVELOPMENT PROJECT (PDP)
STORM WATER QUALITY MANAGEMENT PLAN (SWQMP)
FOR
THE PRESERVE AT QUARRY CREEK
(3335 MARRON ROAD)
PROJECT ID: T.B.D.
ENGINEER OF WORK:
Will sign and stamp upon approval
Wayne W. Chang, MS, PE 46548, Expires 6/30/2021
PREPARED FOR:
EL SAL TO FALLS, LLC
211 MAIN STREET
VISTA, CA 92084
(760) 822-9347
PREPARED BY:
Chlll~[lli(]m
Civil Engineering • Hydrology O Hydraulics • Sedimentation
P.O. Box 9496
Rancho Santa Fe, CA 92067
(858) 692-07 60
DATE:
MAY 26, 2020
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Certification Page
Project Vicinity Map
TABLE OF CONTENTS
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 and Soil Classifications Map
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 and DCV Worksheets / Calculations
Attachment 2: Backup for PDP Hydromodification Control Measures -N/A. Project is Exempt
Attachment 3: Structural BMP Maintenance Thresholds and Actions
Attachment 4: Single Sheet BMP (SSBMP) Exhibit
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CERTIFICATION PAGE
Project Name: 3335 Marron Road -The Preserve at Quarry Creek
Project ID:
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.
Will sign upon approval PE 46548, Expires 6/30/2021
Engineer of Work's Signature, PE Number & Expiration Date
Wayne W. Chang
Print Name
Chang Consultants
Company
May 26, 2020
Date
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PACIFIC
OCEAN
PROJECT VICINITY MAP
CITY OF ENCINITAS
NOT TO
SCALE
CITY OF VISTA
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Carlsbad
STORM WATER STANDARDS
QUESTIONNAIRE
Development Services
Land Development Engineering
1635 Faraday Avenue
(760) 602-2750
www.carlsbadca.gov
E-34
f 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: 3335 Marron Road -The Preserve at Quarry Creek PROJECT ID: T.B.D.
ADDRESS: 3335 Marron Road , Carlsbad, CA 92010 APN : 167-040-49
The project is (check one): D New Development IZI Redevelopment
The total proposed disturbed area is: 52,708 ft2(1.21 ) acres
The total proposed newly created and/or replaced impervious area is: 13,645 ft2 (0.31 ) 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 NIA SWQMP#: N/A
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 REV 02/16
STEP1
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 □ Ill 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):
NIA
If you answered "no" to the above question, the project is a 'development project', go to Step 2.
STEP2
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; □ Ill 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 quidance?
2. Retrofitting or redeveloping existing paved alleys, streets, or roads that are designed and constructed in □ Ill 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? □ Ill
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):
N/A
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 02/16
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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, □ 121
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 over the entire project site on an existing site of 10,000 square feet or 121 □ more of impervious surface? This includes commercial, industrial, residential, mixed-use, and public
development projects on public or private land.
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 □ 121
refreshment stands selling prepared foods and drinks for immediate consumption (Standard Industrial
Classification (SIC) code 5812).
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 □ Ill
development project includes development on any natural slope that is twenty-five percent or qreater.
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 Ill □ 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 surface collectively over the entire project site and supports a street, road , highway Ill □ freeway or driveway? 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 □ Ill
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).*
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 □ Ill 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.
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 □ Ill 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 dav.
10. Is your project a new or redevelopment project that results in the disturbance of one or more acres of land Ill □ 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 □ Ill
21.203.040)
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, 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 statinq "My project is a 'STANDARD PROJECT' ... " and complete applicant information.
E-34 Page 3 of 4 REV 02/16
STEP4
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) = 0 sq. ft. □ Ill
Total proposed newly created or replaced impervious area (8) = 13,645 sq. ft.
Percent impervious area created or replaced (B/A)*100 = < 50 %
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 BM P's required for PDP apply to the entire development. Go to step 5, check the
check the first box statinq "My project is a PDP ... "and complete applicant information.
STEPS
CHECK THE APPROPRIATE BOX AND COMPLETE APPLICANT INFORMATION
Ill 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 Name: David Lowen Applicant Title: Developer/Engineer
Applicant Signature: Date:
.. • Environmentally Sens1t1ve 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 (1 994) 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.
Th' B fi c· 0 IS ox or 1ty Use n/y
YES NO
City Concurrence: □ □
By:
Date:
Project ID:
E-34 Page 4 of 4 REV 02/16
SITE INFORMATION CHECKLIST
Proiect Summary Information
Project Name 3335 Marron Road -The Preserve at
Quarry Creek
Project ID T.B.D.
Project Address 3335 Marron Road
Carlsbad.CA 92010
Assessor's Parcel Number(s) (APN(s)) 167-040-49
Project Watershed (Hydrologic Unit) Carlsbad Hydrologic Unit (904.00)
Parcel Area 2.12 Acres (92,347 Square Feet)
Existing Impervious Area
0.00 Acres (0 Square Feet) (subset of Parcel Area)
Area to be disturbed by the project
1.21 Acres (52,708 Square Feet) (Project Area)
Project Proposed Impervious Area
0.31 Acres (13,645 Square Feet) (subset of Project Area)
Project Proposed Pervious Area 0.90 Acres (39,063 Square Feet) (subset of Project Area)
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):
D Existing development
X Previously graded but not built out
D Agricultural or other non-impervious use
D Vacant, undeveloped/natural
Description / Additional Information:
The site was previously graded into a gently-sloping developable pad by the South Coast
Materials Quarry (Quarry Creek) project (Project No. SUP 07-03, Drawing No . 470-SA).
Existing Land Cover Includes (select all that apply):
X Vegetative Cover
X Non-Vegetated Pervious Areas
□ Impervious Areas
Description / Additional Information:
The existing site contains the graded pad, which is a non-vegetated pervious area. The site also
contains landscaping along the easterly edge, northeast corner, and southerly slope.
Underlying Soil belongs to Hydrologic Soil Group (select all that apply):
D NRCS Type A
D NRCS Type B
X NRCS Type C
X NRCS Type D
Approximate Depth to Groundwater (GW):
D GW Depth < 5 feet
D 5 feet < GW Depth < 10 feet
□ 10 feet < GW Depth < 20 feet
X GW Depth > 20 feet. Groundwater was not encountered in test borings. Depth is likely
below Buena Vista Creek bed . Creek bed is> 20 feet below pad.
Existing Natural Hydrologic Features (select all that apply):
□ Watercourses
o Seeps
D Springs
□Wetlands
X None
Description/ Additional Information:
The project will be constructed on a graded pad containing no natural hydrologic features.
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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 southerly portion of the site contains a manufactured 2: 1 slope that was created by the past
South Coast Materials Quarry mining operation. The northerly portion of the site contains a
development pad that was graded as part of the quarry reclamation and slopes gently towards
the northwest. The manufactured slope extends above the property boundary and is
approximately 160-foot high near the site. The slope contains concrete terrace ditches and
down drains that convey storm runoff to the bottom of the slope. One of the down drains outlets
onto the pad and contains a tributary area just over 2 acres. The combined slope and pad runoff
flows into a bioretention basin at the northwest corner of the pad. Storm runoff is conveyed out
of the bioretention basin by a public underground storm drain that continues west along Marron
Road and then north along El Saito Flats Street to Buena Vista Creek.
Description of Proposed Site Development and Drainage Patterns
Project Description / Proposed Land Use and/or Activities:
The project will be developed into a Children's Paradise Preschool and Infant Center. The
project will support the preschool building , a parking lot, and yard areas.
LisUdescribe proposed impervious features of the project (e.g., buildings, roadways, parking
lots, courtyards, athletic courts, other impervious features):
The impervious features include the preschool building , driveway aprons, hardscape, and
exterior trash enclosure.
LisUdescribe proposed pervious features of the project (e.g., landscape areas):
The pervious features include landscape areas, pervious pavers in the parking lot, and a
biofiltration basin for pollutant and flow control of the project runoff.
Does the project include grading and changes to site topography?
XYes
□No
Description / Additional Information:
The site is currently gently sloping. Minor grading will need to be performed based on the
grading design.
Does the project include changes to site drainage (e.g., installation of new storm water
conveyance systems)?
XYes
□No
Description / Additional Information:
The site drainage patterns will be generally maintained and the runoff will continue to be
conveyed to the public storm drain along Marron Road . Storm runoff from the southerly hillside
will be captured by a proposed concrete swale, Type F catch basin, and Brooks 2424 CB catch
basin constructed along the existing toe of slope. These drainage facilities will prevent the
hillside runoff from commingling with the project runoff. These drainage facilities will connect to
a proposed on-site storm drain that conveys runoff to the existing Marron Road storm drain.
The project runoff will be collected by a separate private storm drain system and conveyed to a
proposed biofiltration basin at the northwest corner of the site for pollutant and flow control. The
biofiltration basin will replace the existing bioretention basin. Storm runoff from the biofiltration
basin will enter the existing Marron Road storm drain .
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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
□ Interior floor drains and elevator shaft sump pumps
□ 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
□Foodservice
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
X 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):
Site runoff is captured by a public storm drain in Harding Street. The storm drain continues north
to Chestnut Avenue, turns west and continues on Chestnut Avenue to the railroad tracks. The
storm drain then parallels the railroad tracks to the south and discharges into the Agua
Hedionda 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 Creek Sediment toxicity and A TMDL is still required.
selenium.
Buena Vista Lagoon Indicator bacteria, nutrients, A TMDL is still required.
and sedimentation/siltation.
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):
Pollutant
Sediment
Nutrients
Heavy Metals
Organic Compounds
Trash & Debris
Oxygen Demanding
Substances
Oil & Grease
Bacteria & Viruses
Pesticides
X -Anticipated
P -Potential
Not Applicable to
the Project Site
✓
Also a Receiving
Anticipated from the Water Pollutant of
Project Site Concern
p ✓
p ✓
X
p
X
p
X
p
Hydromodification Manaaement Reauirements
Do hydromodification management requirements apply (see Section 1.6 of the BMP Design
Manual)?
X 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.
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 ifa 'No' answer has been selected above):
Critical Coarse Sediment Yield Areas*
*This Section only reauired if hydromodification manaaement reauirements 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 Section 6.2 of the BMP Design Manual
been performed?
D 6.2.1 Verification of Geomorphic Landscape Units (GLUs) Onsite
□ 6.2.2 Downstream Systems Sensitivity to Coarse Sediment
□ 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?
D 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.
□ 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 :
The Carlsbad WMAA's Potential Critical Coarse Sediment Yield Areas exhibit shows CCSYA's
near the southerly portion of the site. However, the entire project site and surrounding area have
been graded and disturbed, so no CCSYA's will be within the project footprint.
Flow Control for Post-Project Runotr
*This Section onlv reauired if hvdromodification management reauirements aooly
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.
The project runoff is conveyed by a public storm drain system to Buena Vista Creek northwest
of the site. The outlet into Buena Vista Creek is the first location where the runoff enters a
natural stream system subject to hydromodification impacts. Therefore, the outlet is the project's
POC and is labeled POC A.
Has a geomorphic assessment been performed for the receiving channel(s)?
X No, the low flow threshold is 0.1 Q2 (default low flow threshold)
□ Yes, the result is the low flow threshold is 0.1 Q2
D Yes, the result is the low flow threshold is 0.3O2
D Yes, the result is the low flow threshold is 0.5O2
If a geomorphic assessment has been performed, provide title, date, and preparer:
N/A
Discussion/ Additional Information: (optional)
N/A
Other Site Reauirements 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.
The project's geotechnical engineer, SMS Geotechnical Solutions, Inc., has determined that full
and partial infiltration are not feasible at the site.
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.
N/A.
(... City of
Carlsbad
STANDARD PROJECT
REQUIREMENT
CHECKLIST
E-36
Project lnfonnation
Project Name: 3335 Marron Road -The Preserve at Quarry Creek
Project ID: T.B .D.
DWG No. or Building Permit No.: T.B.D.
Source Control BMPs
Development Services
Land Development Engineering
1635 Faraday Avenue
{760) 602-2750
www.carlsbadca.gov
.
'
i t,·
l'~ .
All development projects must implement source control BMPs SC-1 through SC-6 where appl icable and feasible. See
Chapter 4 and Appendix E.1 of the BMP Design Manual 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 Ill Yes □ No 0 N/A
Discussion/justification if SC-1 not implemented:
N/A
SC-2 Storm Drain Stenciling or Signage Ill Yes □ No □ N/A
Discussion/justification if SC-2 not implemented:
N/A
SC-3 Protect Outdoor Materials Storage Areas from Rainfall , Run-On, Runoff, and Wind □ Yes □ No Ill N/A Dispersal
Discussion/justification if SC-3 not implemented:
N/A
E-36 Page 1 of 4 Revised 03/16
Source Control Reauirement (continued) Annlied?
SC-4 Protect Materials Stored in Outdoor Work Areas from Rainfall, Run-On, Runoff, and □Yes □ No Ill N/A Wind Dispersal
Discussion/justification if SC-4 not implemented:
N/A
SC-5 Protect Trash Storage Areas from Rainfall, Run-On, Runoff, and Wind Dispersal Ill Yes □ No □ N/A
Discussion/justification if SC-5 not implemented:
N/A
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 Appendix E.1 of BMP Manual for guidance).
i;zi On-site storm drain inlets Ill Yes □ No □ N/A
□ Interior floor drains and elevator shaft sump pumps □Yes □ No Ill N/A
□ Interior parking garages □ Yes □ No i;zi N/A
Ill Need for future indoor & structural pest control i;ziYes □ No □ N/A
Ill Landscape/Outdoor Pesticide Use i;zi Yes □ No □ N/A
□ Pools, spas, ponds, decorative fountains, and other water features □Yes □ No Ill N/A
□Foodservice □ Yes □ No i;zi NIA
i;zi Refuse areas i;ziYes □ No □ N/A
□ Industrial processes □Yes □ No LZ1 N/A
□ Outdoor storage of equipment or materials □Yes □ No Ill N/A
□ Vehicle and Equipment Cleaning □ Yes D No '21 N/A
□ Vehicle/Equipment Repair and Maintenance □ Yes □ No Ill N/A
□ Fuel Dispensing Areas □Yes □ No Ill N/A
□ Loading Docks □ Yes □ No i;zi N/A
i;zi Fire Sprinkler Test Water i;zi Yes □ No □ N/A
Ill Miscellaneous Drain or Wash Water i;zi Yes □ No □ N/A
Ill Plazas, sidewalks, and parkinq lots i;zi Yes □ No □ N/A
For "Yes" answers, identify the additional BMP per Appendix E.1. Provide justification for "No" answers.
The on-site storm drain inlets will be labeled. Pest control shall only be used, if needed. Maintain landscaping using
minimum or no pesticides. The outdoor refuse area shall be enclosed , covered, and contain an impervious floor. Fire
spin kier test water will drain to the sanitary sewer or a BMP. Miscellaneous drain water will drain to the sanitary sewer
where required by code, or will drain to a BMP. Plazas, sidewalks, and parking lots shall be swept regularly to prevent the
accumulation of litter and debris.
E-36 Paqe 2 of 4 Revised 03/16
Site Design BMPs
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 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 Appendix E.2 thru E.6 of
the Model BMP Design Manual. 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.
• "N/A" 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.
Source Control Requirement I Applied?
SD-1 Maintain Natural Drainaqe Pathways and Hydrologic Features I □Yes I □ No I Ill NIA
Discussion/justification if SD-1 not implemented:
NIA. The entire site has been graded.
SD-2 Conserve Natural Areas, Soils, and Vegetation I □Yes I □ No I'll N/A
Discussion/justification if SD-2 not implemented:
N/A. The en tire site has been graded. Existing vegetation on the southerly hillside will be maintained.
SD-3 Minimize Impervious Area I 'lJ Yes I □ No I □ NIA
Discussion/justification if SD-3 not implemented:
N/A
SD-4 Minimize Soil Compaction I 'll Yes I □ No I □ N/A
Discussion/justification if SD-4 not implemented:
N/A
SD-5 Impervious Area Dispersion I Ill Yes I □ No I □ N/A
Discussion/justification if SD-5 not implemented:
N/A
E-36 Paoe 3 of 4 Revised 03/16
Source Control Reaulrement (continued) I Annlled?
SD-6 Runoff Collection I Ill Yes I □ No I □ N/A
Discussion/justification if SD-6 not implemented:
N/A
SD-7 Landscaping with Native or Drought Tolerant Species I Ill Yes I □ No I □ N/A
Discussion/justification if SD-7 not implemented:
N/A
SD-8 Harvesting and Usinq Precipitation I □Yes I O No I Ill N/A
Discussion/justification if SD-8 not implemented:
N/A
E-36 Paoe 4 of 4 Revised 03/16
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). 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.
The procedures in the 2016 Carlsbad BMP Design Manual (Manual) were followed in selecting
and then sizing the appropriate BMPs for the project. The Manual requires that harvest and use,
then infiltration be considered before biofiltration.
Harvest and use is assessed by comparing the design capture volume with the on-site water
use. The design capture volume (DCV) is the 24-hour, 85th percentile storm volume at the site.
Figure 8.1-1 from the Manual shows that the 24-hour, 85th percentile precipitation is 0.62 inches
(see Attachment 1C). The DCV based on this value is calculated on attached Worksheet 8 .2-1
and is 1,530 cubic feet. Form 1-7 from the manual indicates that the 36 hour demand must be
greater than 0.25DCV (0.25 x 1,530 cf= 382.5 cf or 2,861 gallons) for harvest and use to be
feasible. The demand from attached Table 8 .3-1 is 33 gallons per non-student school
employees per day (24 hours) or 49.5 gallons per 36 hours. Based on this, the site would need
to have 58 employees (2,861 + 49.5 = 58) for harvest and use to be feasible. The preschool will
not have near 58 employees, so harvest and use is not feasible.
----.. ----
-..
-
-.. ..
-.. -.. --
The project's geotechnical engineer, SMS Geotechnical Solutions, Inc., has determined that full
and partial infiltration are not feasible at the site (see Attachment 1 D).
The next BMP in the hierarchy is biofiltration. A biofiltration basin has been sized using
Worksheet 8.5-1 from the Manual (see Attachment 1 E) and the basin area needs to cover 888
square feet for pollutant control. The existing bioretention basin at the northwest corner of the
site will be replaced with the biofiltration basin.
Structural BMP Summary Information
[Copy this page as needed to provide information for each individual proposed
structural BMP]
Structural BMP ID No. Biofiltration Basin 1
DWG: Grading Plan Sheet No. 2
Type of structural BMP:
D Retention by harvest and use (H U-1)
D Retention by infiltration basin (INF-1)
D Retention by bioretention (INF-2)
D Retention by permeable pavement (INF-3)
D Partial retention by biofiltration with partial retention (PR-1)
X 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:
D Pollutant control only
X Hydromodification control only
D Combined pollutant control and hydromodification control
D Pre-treatmenUforebay for another structural BMP
□ Other (describe in discussion section below)
Discussion (as needed):
The project proposes a biofiltration basin at the northwest corner of the site for pollutant and
flow control of the project's storm runoff.
-.. -
------..
-
--
--
-
-----•
----
Attachment
Seauence
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:
Contents Checklist
Attachment 1 a OMA Exhibit (Required) X Included
See OMA Exhibit Checklist on the
back of this Attachment cover sheet.
(24"x36" Exhibit typically required)
Attachment 1b Tabular Summary of DMAs Showing X Included on OMA Exhibit in
Attachment 1 c
Attachment 1 d
OMA ID matching OMA Exhibit, OMA Attachment 1a
Area, and OMA Type (Required)* □ Included as Attachment 1 b,
*Provide table in this Attachment OR
on OMA Exhibit in Attachment 1 a
Form 1-7, Harvest and Use Feasibility
Screening Checklist (Required unless
the entire project will use infiltration
BMPs)
Refer to Appendix B.3-1 of the BMP
Design Manual to complete Form 1-7.
Form 1-8, Categorization of Infiltration
Feasibility Condition (Required
unless the project will use harvest and
use BMPs)
Refer to Appendices C and D of the
BMP Design Manual to complete
Form 1-8.
separate from OMA Exhibit
X Included
□ Not included because the entire
project will use infiltration BMPs
X Included
D Not included because the entire
project will use harvest and use
BMPs
Attachment 1 e Pollutant Control BMP Design X 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 DMA
Exhibit:
The OMA Exhibit must identify:
X Underlying hydrologic soil group
X Approximate depth to groundwater
X Existing natural hydrologic features (watercourses, seeps, springs, wetlands)
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 (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)
X Structural BMPs (identify location and type of BMP)
I
I
I
I
D
I
I
I
=
I
I
I
~ -~ . _. EXISTING STORM DRAIN CONVEYS
' -~ PROJECT STORM RUNOFF TO POC A
,_ I ~6-IN BUENA VISTA CREEK MARRON ROAD
~
-
/ ,. ,., -------•• ~ --L.__ r.:::::____ ---..;.-
--------/ ~----t~~~-~, ~ , / (~ I~ ~~ . ·-,._ -----=== ~ l • . ,,. ' ,·-~·, ,t,... ~ _ lnlfr,J 1~ C" 'Tn C"Y TVC.C: ~-
2.0~ PARKING ~EA = 15830.2 S.F.
(Trf) /
I -' 'i l '
-~ ~ I . / , ,,.,._ ~ i:--""
~Y/
X147.7
-7.9
X 146.8
~-
. ---
-~
.... ' PRESCHOOL
PAO • 140.0
r.F. • 140.7
(TYP) BLOC AREA • 11930 ------~
::..-----' I \\
1" = 50'
~
0 50
LEGEND: ---
DRAINAGE MANAGEMENT AREA (DMA 1) TRIBUTARY
TO PROPOSED BIOFIL TRA TION BASIN -60,352 SF (1 .39 AC)
PROPOSED DRAINAGE FACILITY
PROPOSED FLOW CONTROL BIOFIL TRA TION BASIN -1,396 SF
I I PROPOSED IMPERVIOUS AREA (ROOF, CONCRETE
.__ _ ____, PAVEMENT) -13,645 SF
I I PROPOSED PARKING LOT PERVIOUS PAVERS -15,830 SF
I I PROPOSED LANDSCAPING -30,877 SF
+8.4 X 148.6
~.,,.-~-
...... ~ _.,,
NOTES:
THE HYDROLOGIC SOIL GROUP AT THE SITE IS PRIMARILY D WITH A SMALL AREA OF C (941
SF) AT THE NORTHWEST CORNER. THE APPROXIMATE DEPTH TO GROUNDWATER IS OVER 20
FEET. THERE ARE NO NATURAL HYDROLOGIC FEATURES OR CRITICAL COURSE SEDIMENT
YIELD AREAS AT THE SITE. THE PROJECT PROPOSES A DUAL STORM DRAIN SYSTEM TO
PREVENT THE SOUTHERLY HILLSIDE RUNOFF FROM COMMINGLING WITH THE PROJECT RUNOFF.
THE ON-SITE AREAS BEYOND THE DRAINAGE BASIN BOUNDARY ARE SELF-MITIGATING.
'""-"
ATTACHMENT 2A
HYDROMODIFICATION MANAGEMENT EXHBIT
Appendix I: Forms and Checklists
ATTACHMENT 1C
Harvest and Use Feasibility Checklist Form 1-7
1. Is there a demand for harvested water (check all that apply) at the project site that is reliably present during
the wet season?
D Toilet and urinal flushing
D Landscape irrigation
0 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]
Per "Summary of PDP Structural BMPs" section in SWQMP, there is not enough
demand for harvest and use to be feasible.
3. Calculate the DCV using worksheet B.2-1.
D CV = 1,530 (cubic feet)
3a. Is the 36 hour demand greater
than or equal to the DCV?
D Yes / □No c>
,0,
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.
36. Is the 36 hour demand greater than
0.25DCV but less than the full D CV?
D Yes I D 0 c:>
.0,
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.
Is harvest and use feasible based on further evaluation?
D Yes, refer to Appendix E to select and size harvest and use BMPs.
D No, select alternate BMPs.
3c. Is the 36 hour demand
less than 0.25DCV?
~ Yes
i
Harvest and use is
considered to be infeasible.
See attached sheets for DCV, runoff factors, and demand data.
1-2 February 2016
1
2
3
4
5
6
Appendix B: Storm Water Pollutant Control Hydrologic Calculations and Sizing Methods
Worksheet B.2-1. DCV
Design Capture Volume Worksheet B-2.1
85th percentile 24-hr storm depth from Figure B.1-1 d= 0.62 inches
Area tributary to BMP (s) A= 1.39 acres
Area weighted runoff factor (estimate using Appendi'C 0.49 B.1.1 and B.2.1) C= unitless
Tree wells volume reduction TCV= 0 cubic-feet
Rain barrels volume reduction RCV= 0 cubic-feet
Calculate DCV =
(3630 x C x d x A) -TCV -RCV DCV= 1,530 cubic-feet
For the overall drainage area (60,352 sf= 1.39 ac) under proposed conditions, the
pervious landscape area covers 30,877 sf, the impervious roof and pavement areas
cover 13,645 sf, and the pervious pavers in the parking lot cover 15,830 sf.
Based on this, the area weighted runoff factor from the equation in B.1.1 on next
sheet is:
((30,877 X 0.1) + ( 13,645 X 0.9) + (15,830 X 0.9] / 60,352 = 0.49
See DCV calculations for each OMA in Attachment 1 E.
B-10 February 2016
Appendix B: Storm Water Pollutant Control Hydrologic Calculations and Sizing Methods
B.1 DCV
DCV is defined as the volume of storm water runoff resulting from the 85th percentile, 24-hr storm
event. The following hydrologic method shall be used to calculate the DCV:
Where:
DCV = C x d x AX 43,560 sf /ac X 1/12 ft/in
DCV = 3,630 x C x d x A
D CV = Design Capture Volume in cubic feet
C = Runoff factor (unitless); refer to section B.1.1
d = 85th percentile, 24-hr storm event rainfall depth (inches), refer to section B.1.3
A = Tributary area (acres) which includes the total area draining to the BMP, including any
offsite or onsite areas that comingles with project runoff and drains to the BMP. Refer
to Section 3.3.3 for additional guidance. Street redevelopment projects consult Section
1.4.2.
B.1.1 Runoff Factor
Estimate the area weighted runoff factor for the tributary area to the BMP using runoff factor (from
Table B.1-1) and area of each surface type in the tributary area and the following equation:
Where:
C = Runoff factor for area X
A, = Tributary area X (acres)
LCxAx C=---
LAx
These runoff factors apply to areas receiving direct rainfall o nly. For conditions in which runoff is
routed onto a surface from an adjacent surface, see Section B.2 for determining composite runoff
factors for these areas.
Table B.1-1: Runoff factors for surfaces draining to BMPs -Pollutant Control BMPs
Surface Runoff Factor
Roofs' 0.90
Concrete or Asphalt' 0.90
Unit Pavcrs (grouted)' 0.90
Decomposed Granite 0.30
Cobbles or Crushed .Aggregate 0.30
, \mended, l'.fulchcd Soils or Landscape 0.1 0
Compacted Soil (e.g., unpaved parking) 0.30
1. Surface is considered impervious and could benefit from use o f Site Design B:\fPs and
adjustment of the runo ff factor per Section B.2.1.
B-2 February 2016
San Diego County
85 th Percentile lsopluvials
Legend
-85th PERCENTILE ISOPLUVIAL
[_ _ _j INCORPORATED CITY
NOTE
The 85th percentile is a 24 hour ratnfall total
It represetns a value such that 85% of the
observed 24 hour ra1nfan totals wtll be less
than that value
N
+ ~--0 t 2 4 9 I
,... .,.tJfC,C' ..... ~ ifetf) #ftttAH 0,A."I ...
(.w.PAE880A ~m 1n..U0Mi laJ1 '101' » ED 0 ~ IIIPI.£: 1,•~'lffl:80F RIC),'Af, T'f~~llll:M'Olt&Nll?Q.U.P ~ TIJJll.-:o,.dEacorc..,~'-",_a,uo,.o
Ragolllf ............ ~a,YIII-........,...,,,... ... _....
-~cl.MCliO n........all\l9talUill .....ad-0
pP!MKll~ ... --,w.~1~-~ ,,..,.., .. ~..--...~t,......,.,.~-~-..... ....-.,ca _,a..., ... ...,_,........,,_......,,._.,.__~h ......... .......,.,,R,t,-,1.......,.~
~la1Ql!IID'4 ... ~ ........ ""'"'' ., .. -.;.-~ .. b.H• ..,~_.,.OfWIIOI, --MIi\
~.&r.e,s
"f'l:Ut~A"l.AII H'Clllfl('l'III 11 NPUt,,...
Appendix B: Storm Water Pollutant Control Hydrologic Calculations and Sizing Methods
Table B.3-1. Toilet and Urinal Water Usage per Resident or Employee
Land Use Type
Residential
Office
Retail
Schools
Yarious Industrial
Uses (excludes
process water)
Toilet User
Unit of
Normalization
Resident
E mployee
(non-visitor)
Employee
(non-visitor)
E mployee
(non-student)
Employee
(non-visitor)
Per Capita Use per
Day
Toilet
Flushing'·
2
18.5
9.0
9.0
6.7
9.0
Urinals3
NA
2.27
2.11
3.5
2
Visitor
Factor'
N.-\
1.1
1.4
6.4
Water
Efficiency
Factor
0.5
0.5
0.5
0.5
0.5
Total Use
per
Resident
or
Employee
9.3
7
(avg)
33
5.5
1-Based on American Waterworks Association Research roundation,1999. Residential Encl Uses of Water. Denver, CO: A \X/W A RF
2 -Based on use of 3.45 gallons per flush and average number of per employee flushes per subscctor, Table D-1 for MWD (Pacific
Institute, 2003)
3 -Based on use of 1.6 gallons per flush, Table D-4 and average number o f per employee flushes per subsector, Appendix D (Pacific
1 nstitute, 2003)
4 -Multiplied by the demand for t0ilct and urinal flushing for the project co account for visitors. Based on proportion of annual use
allocated tO visitors and others (includes students for schools; about 5 students per employee) for each subsect◊r in Table D -1 and D-
4 (Pacific I nstitutc, 2003)
5 -Accounts for requirements co use ultra low flush toilets in new development projects; assumed that requirements will reduce toilet
and urinal flushing demand by half on average compared tO literature estimates. Ultra low flush toilets arc required in all new
construction in California as of January 1, 1992. Ultra low flush toilets must use no more than 1.6 gallons per flush and Ultra low
flush urinals must use no more than 1 gallon per flush. otc: 1 f zero flush urinals arc being used, adjust accordingly.
B.3.2.2 General Requirements for Irrigation Demand Calculations
The following guidelines should be followed for computing harvested water demand from landscape
irrigation:
• If reclaimed water is planned fo r use for landscape irrigation, then the demand for harvested
storm water should be reduced by the amount of reclaimed water that is available during the
wet season.
• Irrigation rates should be based on the irrigation demand exerted by the types of landscaping
that are proposed for the project, with consideration for water conservation requirements.
• Irrigation rates sho uld be estimated to reflect the average wet season rates (defined as
ovember through pril) accounting for the effect of storm events in o ffsetting harvested
water demand. In the absence o f a detailed demand study, it sho uld be assumed that irrigation
demand is not present during days with greater than 0.1 inches of rain and the subsequent 3-
day period. T his irrigation shutdown period is consistent with standard practice in land
application of wastewater and is applicable to storm water to prevent irrigation from resulting
B-13 February 2016
ATTACHMENT 1 D
Appendix C: GeotecbnicaJ and Groundwater Investigation Requirements
Worksheet C.4-1: Categorization of lnflltratlon Feasibility Condition Based on Geotechnical Conditions'
C.iteguriz,lliu11 of lnfiltr,1tion h•,1s1htl11y Cond1tw11 bJst•d on Worl\shect C./, 1 Form I -
Geolt'lhlllldl Conditions SA"
Part 1 -Full Infiltration Feasibility Screening Criteria
DMA(s) Being Analyzed: Project Phase:
P-201 , P-202, P-203, P-204 Planning
Criteria 1: Infiltration Rate Screening
Is the mapped hydrologic soil group according to the NRCS Web Soil Survey or UC Davis Soil
Web Mapper Type A or Band corroborated by available site soil datan?
□ Yes; the DMA may feasibly support full infiltration. Answer "Yes" to Criteria 1 Result or
continue to Step 1B if the applicant elects to perform infiltration testing.
1A □ No; the mapped soil types are A or B but is not corroborated by available site soil data
(continue to Step tB).
QII No; the mapped soil types are c, D, or "urban/unclassified" and is corroborated by
available site soil data Answer "No" to Criteria 1 Result.
D No; the mapped soil types are C, D, or "urban/unclassified" but is not corroborated by
available site soil data (continue to Step tB).
Is the reliable infiltration rate calculated using planning phase methods from Table D.3-1?
1B □ Yes; Continue to Step 1C.
D No; Skip to Step lD.
Is the reliable infiltration rate calculated using planning phase methods from Table D.3-1
greater than 0.5 inches per hour?
tC □ Yes; the DMA may feasibly support full infiltration. Answer "Yes" to Criteria 1 Result.
□ No; full infiltration is not required. Answer 11No" to Criteda 1 Result.
Infiltration Testing Method. Is the selected infiltration testing method suitable during the
design phase (see Appendix D.3)? Note: Alternative testing standards may be allowed with
tD appropriate rationales and documentation.
D Yes; continue to Step lE.
D No; select an appropriate infiltration testing method.
9 Note that it is not required to investigate each and every criterion in the worksheet, a single "no"
answer in Part 11 Part 21 Part 31 or Part 4 detennines a full, partial, or no infiltration condition.
•• This form must be completed each time there is a change to the site layout that would affect the
infiltration feasibility condition. Previously completed forms shall be retained to document the
evolution of the site storm water design.
11 Available data includes site-specific sampling or observation of soil types or texture classes, such as
obtained from borings or test pits necessary to support other design elements.
C-16 The City of San Diego I Storm Water Standards I October 201 8 Edition
Part 1: BMP Design Manual SD.)
-
Appendix C: Geotechnical and Groundwater Investigation Requirements
(alrgoriz.Jlion of lnfiltr,111011 Fe;i<;ih11ity Condition based on Workshcel (' t, 1. l·urm 1-
1E
IF
lG
Criteria 1
Result
Geotechmcal Cont!1tions 81\''
Number of Percolation/Infiltration Tests. Does the infiltration testing method performed
satisfy the minimum number of tests specified in Table D.3-2?
o Yes; continue to Step lF.
o No; conduct appropriate number of tests.
Factor of Safety. Is the suitable Factor of Safety selected for full infiltration design? See
guidance in D.5; Tables D.5-1 and D.5-2; and Worksheet D.5-1 (Form l-9).
D Yes; continue to Step 1G.
D No; select appropriate factor of safety.
Full Infiltration Feasibility. Is the average measured infiltration rate divided by the Factor
of Safety greater than 0.5 inches per hour?
D Yes; answer "Yes" to Criteria 1 Result.
D No; answer "No" to Criteria 1 Result.
Is the estimated reliable infiltration rate greater than 0.5 inches per hour within the OMA
where runoff can reasonably be routed to a BMP?
O Yes; the DMA may feasibly support full infiltration. Continue to Criteria 2.
O No; full infiltration is not required. Skip to Part 1 Result.
Summarize infiltration testing methods, testing locations, replicates, and results and summarize
estimates of reliable infiltration rates according to procedures outlined in D.5. Documentation should
be included in project geotechnical report.
See report
C-17 The City of San Diego I Storm Water Standards I October 2018 Edition
Part 1: BMP Design Manual
Appendix C: Geotecbnkal and Groundwater Investigation Requirements
Categorization of Infiltration Feasibility Condition based on Worksheet C.4-1. Form 1-
Gl'ott•chniral Conditions 81\'"
Criteria 2: Geologic/Geotechnical Screening
2A
2A-1
2A-2
2.A-3
2B
2B-1
2B-2
If all questions in Step 2A are answered "Yes,U continue to Step 2B.
For any "No,, answer in Step 2A answer "No" to Criteria 2, and submit an ((Infiltration
Feasibility Condition Letter" that meets the requirements in Appendix C.u. The
geologic/geotechnical analyses listed in Appendix C.2.1 do not apply to the OMA because one
of the following setbacks cannot be avoided and therefore result in the DMA being in a no
infiltration condition. The setbacks must be the closest horizontal radial distance from the
surface edge (at the overflow elevation) of the BMP.
Can the proposed full infiltration BMP(s) avoid areas with existing fill
materials greater than 5 feet thick below the infiltrating surface?
Can the proposed full infiltration BMP(s) avoid placement within 10
feet of existing underground utilities, structures, or retaining walls?
Can the proposed full infiltration BMP(s) avoid placement within so
feet of a natural slope (>25%) or within a distance of 1.5H from fill
slopes where H is the height of the fill slope?
□Yes ONO
□Yes □No
□Yes □No
When full infiltration is determined to be feasible, a geotechnical investigation report must
be prepared that considers the relevant factors identified in Appendix C.2.1.
If all questions in Step 2B are answered ((Yes,,, then answer ((Yes,, to Criteria 2 Result.
If there are "No,, answers continue to Step 2c.
Hydroconsolidation. Analyze hydroconsolidation potential per
approved ASTM standard due to a proposed full infiltration BMP.
Can full infiltration BMPs be proposed within the OMA without
increasing hydroconsolidation risks?
Expansive Soils. Identify expansive soils (soils with an expansion index
greater than 20) and the extent of such soils due to proposed full
infiltration BMPs.
Can full infiltration BMPs be proposed within the DMA without
increasing expansive soil risks?
□Yes
□Yes
□No
□No
C-1 8 The City of San Diego I Storm Water Standards I October 2018 Edition
Part 1: BMP Design Manual
Appendix C: GeotechnicaJ and Groundwater Investigation Requirements
Categorization of Infiltration l-1.'.-isihility Condit1011 haseJ on Worksheet c 4 1 rorm I-
Geoterh111ral Cond1t1ons 8J\''
2B-3
2B-4
2B-5
2B-6
Liquefaction. If applicable, identify mapped liquefaction areas. Evaluate
liquefaction hazards in accordance with Section 6.4-2 of the City of San
Diego's Guidelines for Geotechnical Reports (2011 or most recent
edition). Liquefaction hazard assessment shall take into account any
increase in groundwater elevation or groundwater mounding that could
occur as a result of proposed infiltration or percolation facilities.
Can full infiltration BMPs be proposed within the OMA without
increasing liquefaction risks?
Slope Stability. If applicable, perform a slope stability analysis in
accordance with the ASCE and Southern California Earthquake Center
(2002) Recommended Procedures for Implementation of DMG Special
Publication 117, Guidelines for Analyzing and Mitigating Landslide
Hazards in California to determine minimum slope setbacks for full
infiltration BMPs. See the City of San Diego's Guidelines for
Geotechnical Reports (2011) to determine which type of slope stability
analysis is required.
Can full infiltration BMPs be proposed within the OMA without
increasing slope stability risks?
Other Geotecbnic.al Hazards. Identify site-specific geotechnical
hazards not already mentioned (refer to Appendix C.2.1).
Can full infiltration BMPs be proposed within the OMA without
increasing risk of geologic or geotechnical hazards not already
mentioned?
Setbacks. Establish setbacks from underground utilities, structures,
and/or retaining walls. Reference applicable ASTM or other recognized
standard in the geotechnical report.
can full infiltration BMPs be proposed within the DMA using
established setbacks from underground utilities, structures, and/or
retaining walls?
C-19 The City of San Diego I Storm Water Standards I October 2018 Edition
Part 1: BMP Design Manual
□Yes
□Yes
□Yes
□Yes
□No
□No
□No
□No
SD.}
Appendix C: Geotechnical and Groundwater Investigation Requirements
Catcgonzation of lnhltratmn I eas1b1ltty Co11d1t10n based on Worksheet(',. 1: Form 1-
(;l'ott>rhnital Conditions 81\''
2C
Criteria 2
Result
Mitigation Measures. Propose mitigation measures for each
geologic/geotechnical hazard identified in Step 2B. Provide a discussion
of geologic/geotechnical hazards that would prevent full infiltration
BMPs that cannot be reasonably mitigated in the geotechnical report.
See Appendix C.2.1.8 for a list of typically reasonable and typically
unreasonable mitigation measures.
Can mitigation measures be proposed to allow for full infiltration
BMPs? If the question in Step 2 is answered "Yes, 11 then answer "Yes"
to Criteria 2 Result.
If the question in Step 2c is answered "No, 11 then answer "No" to
Criteria 2 Result.
Can infiltration greater than 0.5 inches per hour be allowed without
increasing risk of geologic or geotechnical hazards that cannot be
reasonably mitigated to an acceptable level?
Summarize findings and basis; provide references to related reports or exhibits.
See report
Part 1 Result -Full Infiltration Geotechnical Screening 12
□Yes
□Yes
Result
If answers to both Criteria 1 and Criteria 2 are "Yes", a full
infiltration design is potentially feasible based on Geotechnical
conditions only.
If either answer to Criteria 1 or Criteria 2 is "No", a full infiltration
design is not required.
D Full infiltration Condition
OIi Complete Part 2
□No
□No
12 To be completed using gathered site information and best professional judgement considering the definition of
MEP in the MS4 Permit. Additional testing and/or studies may be required by City Engineer to substantiate findings.
C-20 The City of San Diego I Storm Water Standards I October 2018 Edition
Part 1: BMP Design Manual SD.)
Appendix C: Geotechnical and Groundwater Investigation Requirements
Categorization of Infiltrdtio11 Fedsibility Condition b.iscd 011 Worksheet C 4 -1: 1-orm l-
Gcoted1111tal Conditions 81\'"
Part 2 -Partial vs. No Infiltration Feasibility Screening Criteria
DMA(s) Being Analyzed: Project Phase:
P-201, P-202, P-203, P-204 Planning
Criteria 3: Infiltration Rate Screening
3A
Criteria 3
Result
NRCS Type c, D, or "urban/unclassified": Is the mapped hydrologic soil group according to
the NRCS Web Soil Survey or UC Davis Soil Web Mapper is Type C, D, or
"urban/unclassified" and corroborated by available site soil data?
D Yes; the site is mapped as C soils and a reliable infiltration rate of 0.15 in/hr. is used to
size partial infiltration BMPS. Answer "Yes" to Criteria 3 Result.
o Yes; the site is mapped as D soils or "urban/unclassified" and a reliable infiltration
rate of 0.05 in/hr. is used to size partial infiltration BMPS. Answer "Yes" to Criteria 3
Result.
o No; infiltration testing is conducted (refer to Table D.3-1), continue to Step 3B.
Infiltration Testing Result: Is the reliable infiltration rate (i.e. average measured
infiltration rate/2) greater than 0.05 in/hr. and less than or equal to 0.5 in/hr?
o Yes; the site may support partial infiltration. Answer "Yes" to Criteria 3 Result.
!XI No; the reliable infiltration rate (i.e. average measured rate/2) is less than 0.05 in/hr.,
partial infiltration is not required. Answer "No" to Criteria 3 Result.
Is the estimated reliable infiltration rate (i.e., average measured infiltration rate/2) greater
than or equal to 0.05 inches/hour and less than or equal to 0.5 inches/hour at any location
within each DMA where runoff can reasonably be routed to a BMP?
o Yes; Continue to Criteria 4.
Ci No: Skip to Part 2 Result.
Summarize infiltration testing and/or mapping results (i.e. soil maps and series description used for
infiltration rate).
See report
C-21 The City of San Diego I Storm Water Standards I October 2018 Edition
Part 1: BMP Design Manual
Appendix C: Geotechnlcal and Groundwate r Investigation Requirements
Cdtegurizdtiun of lnfiltrdtion Fe.isihility Conditiun based on \\'orksheet C 1.-t : form I-
(icotcrhnical Conditions 81\'"
Criteria 4: Geologic/Geotechnical Screening
If all questions in Step 4A are answered "Yes,11 continue to Step 2B.
For any "No" answer in Step 4A answer "No11 to Criteria 4 Result, and submit an "Infiltration
4A Feasibility Condition Letter" that meets the requirements in Appendix C.1.1. The
geologic/geotechnical analyses listed in Appendix C.2.1 do not apply to the OMA because one
of the following setbacks cannot be avoided and therefore result in the OMA being in a no
infiltration condition. The setbacks must be the closest horizontal radial distance from the
surface edge (at the overflow elevation) of the BMP.
4A-l Can the proposed partial infiltration BMP(s) avoid areas with existing □Yes □No fill materials greater than 5 feet thick?
Can the proposed partial infiltration BMP(s) avoid placement within
4A-2 10 feet of existing underground utilities, structures, or retaining □Yes □No
walls?
Can the proposed partial infiltration BMP(s) avoid placement within
4A-3 50 feet of a natural slope (>25%) or within a distance of 1.5H from fill □Yes □No
slopes where H is the height of the fill slope?
When full infiltration is determined to be feasible, a geotechnical investigation report must
be prepared that considers the relevant factors identified in Appendix c .2.1
4B If all questions in Step 4B are answered "Yes,,, then answer 11Yes11 to Criteria 4 Result.
If there are any "No" answers continue to Step 4c.
Hydroconsolidation. Analyze hydroconsolidation potential per
4B-1 approved ASTM standard due to a proposed full infiltration BMP. □Yes □No
can partial infiltration BMPs be proposed within the OMA without
increasing hydroconsolidation risks?
Expansive Soils. Identify expansive soils (soils with an expansion
index greater than 20) and the extent of such soils due to proposed
4B-2 full infiltration BMPs. □Yes □No
Can partial infiltration BMPs be proposed within the DMA without
increasing expansive soil risks?
C-22 The City of San Diego I Storm Wat er Standards I October 2018 Edition
Part 1: BMP Design Manual SD..)
Appendix C: Geotechoical and Groundwater Investigation Requirements
C:itegorizution of InfiltrJtion ft'.1,ihility Cond11wn o.1sed on Worh.shet>l c 1. ~ 1: I orm 1-
<;t>otechnildl l:unclitions 8/\'"
4B-3
4B-4
4B-5
4B-6
4C
Liquefaction. If applicable, identify mapped liquefaction areas.
Evaluate liquefaction hazards in accordance with Section 6.4.2 of the
City of San Diego's Guidelines for Geotechnical Reports (2011).
Liquefaction hazard assessment shall take into account any increase
in groundwater elevation or groundwater mounding that could occur
as a result of proposed infiltration or percolation facilities.
Can partial infiltration BMPs be proposed within the OMA without
increasing liquefaction risks?
Slope Stability. If applicable, perform a slope stability analysis in
accordance with the ASCE and Southern California Earthquake Center
(2002) Recommended Procedures for Implementation of OMG Special
Publication 117, Guidelines for Analyzing and Mitigating Landslide
Hazards in California to determine minimum slope setbacks for full
infiltration BMPs. See the City of San Diego's Guidelines for
Geotechnical Reports (2011) to determine which type of slope stability
analysis is required.
Can partial infiltration BMPs be proposed within the OMA without
increasing slope stability risks?
Other Geotechnical Hazards. Identify site-specific geotechnical
hazards not already mentioned (refer to Appendix c.2.1).
Can partial infiltration BMPs be proposed within the OMA without
increasing risk of geologic or geotechnical hazards not already
mentioned?
Setbacks. Establish setbacks from underground utilities, structures,
and/or retaining walls. Reference applicable ASTM or other
recognized standard in the geotechnical report.
Can partial infiltration BMPs be proposed within the OMA using
recommended setbacks from underground utilities, structures,
and/or retaining walls?
Mitigation Measures. Propose mitigation measures for each
geologic/geotechnical hazard identified in Step 4B. Provide a
discussion on geologic/geotechnical hazards that would prevent
partial infiltration BMPs that cannot be reasonably mitigated in the
geotechnical report. See Appendix C.2.1.8 for a list of typically
reasonable and typically unreasonable mitigation measures.
Can mitigation measures be proposed to allow for partial infiltration
BMPs? If the question in Step 4C is answered "Yes," then answer
"Yes" to Criteria 4 Result.
If the question in Step 4C is answered "No," then answer "No" to
Criteria 4 Result.
C-23 The City of San Diego I Storm Water Standards I October 2018 Edition
Part 1: BMP Design Manual
□Yes
□Yes
□Yes
□Yes
□Yes
□No
□No
□No
□No
□No
SD.)
Appendix C: Geotechnical and Groundwater Investigation Requirements
Cltegorization of lnf1ltrat10n Feasibility Condition bJsl'O on \\'orkshl'l'l c.1.-1: J urm I-
Ccolt>ch111cal Condit1011s XJ\'"
Criteria
4 Result
Can infiltration of greater than or equal to 0.05 inches/hour and less
than or equal to 0.5 inches/hour be allowed without increasing the
risk of geologic or geotechnical hazards that cannot be reasonably
mitigated to an acceptable level?
Summarize findings and basis; provide references to related reports or exhibits.
Part 2 -Partial Infiltration Geotechnical Screening Result13
□Yes
Result
□No
If answers to both Criteria 3 and Criteria 4 are "Yes,., a partial infiltration
design is potentially feasible based on geotechnical conditions only.
If answers to either Criteria 3 or Criteria 4 is "No,., then infiltration of any
volume is considered to be infeasible within the site.
D Partial Infiltration
Condition
DI No Infiltration
Condition
13 To be completed using gathered site information and best professional judgement considering the definition of
MEP in the MS4 Permit. Additional testing and/or studies may be required by City Engineer to substantiate findings.
C-24 The City of San Diego I Storm Water Standards I October 2018 Edition
Part 1: BMP Design Manual
ATTACHMENT 1 E
Appendix B: Storm Water Pollutant Control H ydrologic Calculations and Sizing Methods
Worksheet B.5-1: Simple Sizing Method for Biofiltration BMPs ~-~'"'~ menting retention BMPs 1.530 cubic-feet
Partial Retention
2 Infiltration rate from Form I-9 if partial infiltration is feasible NIA in/hr.
3 Allowable drawdown time for aggregate storage below the underdrain 36 hours
4 Depth of runoff that can be infiltrated [Linc 2 x Line 3] NIA inches
5 Aggregate pore space 0.40 in/in
6 Required depth of gravel below the underdrain [Line 4/ Line 5] NIA inches
7 Assumed surface area of the biofiltration BMP NIA 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 NIA cubic-feet
10 DCV that requires biofiltration [Line 1 -Line 9] NIA cubic-feet
BMP Parameters
11 Surface Ponding [6 inch minimum, 12 inch maximum] 12 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 12 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 o f Detention Storage 20.4 inches [Line 11 + (Line 12 x Line 14) + (Line 13 x Line 5)1
19 Total Depth Treated [Line 17 + Line 18] 50.4 inches
Option 1 -Biofilter 1.5 times the DCV
20 Required biofiltered volume [1.5 x Line 10] 2,295 cubic-feet
21 Required Footprint [Line 20/ Line 19] x 12 546 sq-ft
Option 2 -Store 0.75 of remailllll2'.' DCV in pores and pondine:
22 Required Storage (surface+ pores) Volume [0.75 x Line 101 l , 148 cubic-feet
23 Required Footprint [Line 22/ Line 18] x 12 675 sq-ft
Footprint of the BMP
24 Area draining to the BtvIP 60,352 sq-ft
25 Adjusted Runoff Factor for drainage area (Refer to Appendix B.1 and B.2) 0.49
26 tvlinimum BMP Footprint [Line 24 x Line 25 x 0.03] 888 sq-ft
27 Footprint of the BMP = Maximum(rvlinimum(Line 21, Line 23), Line 26) 888 sq-ft
Note: I .inc 7 is used to estimate the amount of volume retained by the B.\n>. Update assumed surface area in I .inc 7 unnl
its ec1uivalcnt to the required bioliltration footprint (either I .inc 21 or I .inc 23)
B-26 February 2016
...
..
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 X Included
Exhibit (Required) .. See Hydromodification Management
Exhibit Checklist on the back of this
Attachment cover sheet.
Attachment 2b Management of Critical Coarse X Exhibit showing project drainage .. Sediment Yield Areas (WMAA boundaries marked on WMAA
Exhibit is required, additional Critical Coarse Sediment Yield
analyses are optional) Area Map (Required) ...
... See Section 6.2 of the BMP Design Optional analyses for Critical
Manual. Coarse 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 X Not performed
Receiving Channels (Optional) □ Included
See Section 6.3.4 of the BMP Design -Manual.
• Attachment 2d Flow Control Facility Design and X Included
Structural BMP Drawdown -Calculations (Required)
See Chapter 6 and Appendix G of
the BMP Design Manual
... .. ..
... ..
... -..
...
..
..
-..
-----..
-
---
---
-
◄
..
-..
-.. ----
Use this checklist to ensure the required information has been included on the
Hydromodification Management Exhibit:
The Hydromodification Management Exhibit must identify:
X Underlying hydrologic soil group
X Approximate depth to groundwater
X Existing natural hydrologic features ( watercourses, seeps, springs, wetlands)
X Critical coarse sediment yield areas to be protected (if present)
X Existing topography
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 Point(s) of Compliance (POC) for Hydromodification Management
X Existing and proposed drainage boundary and drainage area to each POC (when necessary,
create separate exhibits for pre-development and post-project conditions)
X Structural BMPs for hydromodification management (identify location, type of BMP, and
size/detail)
oETENsI0N BASIN = , 400 s.r. ,
~!,f 2.0,: -PARKING ('REA I= 15830.2 S.F.
1 :;j" HD~E STi!tRM dRAIN F'IPI
I
(j f)
IF T~VEL
47-PARKING SPACES
W/4 HC ONLY
LL_____C
~ t TOP-140.0 -~ ~---l-llR~RtJ,,,;;e~:,~;~,,,,,r;;;J;;;;t~;J,, PCC SUWAU<_ 1;~~!!¥!g :::i: FL:/38.74 '1r>>>>»J»»ffe ' ,1111111 ,,,,,,,,,,,,,~
\
\
\) . HbPE STORL
~V RPFllE so
'\
\
,\.
. ::\.,
'\
\
.. _,._ ~ ....... -~ ----------------------------------=--, -------~-
---=--~ -----===----===
PAD • 140.0 r.r. -140.7 EIUlC: M£A -11930 s.r. 'i I
I I
t>t : : 1~ I I c,: ..: '°' <((/)
• . I I ~~
r»<'l<'IUll~lll~ I >' ~ . i•
..c----~--JVL ---~--
[ANAGEMENT AREA (OMA 1) lRIBUTARY ~ ~~
,D BIOFIL lRA TION BASIN -60,352 SF (1 .39 AC) ~-
)RAIN AGE FACILITY
=-LOW CONTROL BIOFIL TRATION BASIN -1,396 SF
MPERVIOUS AREA (ROOF, CONCRETE
-13,645 SF
NOTES: THE HYDROLOGIC SOIL GROUP AT THE SITE IS PRIMARILY D WITH ,
SF) AT THE NORTHWEST CORNER. THE APPROXIMATE DEPTH TO GI
FEET. THERE ARE NO NA TUR AL HYDROLOGIC FEATURES OR CRITICJ
YIELD AREAS AT THE SITE. THE PROJECT PROPOSES A DUAL STOF
PREVENT THE SOUTHERLY HILLSIDE RUNOFF FROM COMMINGLING WI
THE ON-SITE AREAS BEYOND THE DRAINAGE BASIN BOUNDARY Ar
~gend
Watershed Boundaries
Municipal Boundaries
Rivers & Streams
Regional WMAA Streams
ATTACHMENT 2B
Potential Critical Coarse Sediment Yield Areas
,.,.-; ;¥,
This exhibit identifies CC SY A's from the Carlsbad WMAA. CCSYA's are near the southerly portion of the site.
However, the entire project site and surrounding area have been graded and disturbed, so no CCSYA's will
be within the project footprint.
ATTACHMENT 2D
BMP Sizing Spreadsheet V3.0
Project Name: The Preserve at Quarry Creek
Project Applicant: El Saito Falls, LLC
Jurisdiction: City of Carlsbad
Parcel {APN): 167-040-49
Hydrologic Unit: Carlsbad
Rain Gauge : Oceanside
Total Project Area {sf): 60,352
Channel Susceptibility: High
BMP Sizing Spreadsheet V3.0
Project Name: The Preserve at Quarry Creek Hydrologk Unit: Carlsbad
Project Applicant: El Saito Falls, LLC Rain Gau1e: Oceanside
JurisdKtion: City of Carlsbad Total Project Area: 60,352
Parcel (APN): 167-040-49 low Flow Threshold: 0.1Q2
BMP Name: 81ofihrat1on Basin SMP Type: Bio filtration
SMP Native Soil Type: D BMP Infiltration Rate (in/hr 0.025
Areas Draining to BMP HMP Sizing Factors Minimum BMP Size
Area Weighted Runoff
OMA Pre Project So,I Post Project Factor Surface Area Surface Area (SF)
Name Area (sf) Type Pre•Project Slope Surface Type (Table G.2-1)1
R1,ofs/Hards◄ a~ 13,645 D Flat Roofs 1.0 0.07 9SS
Parkmg lot 15,830 D Flat Sohd Unit Pavers on granular base 0.2 0.07 222
lan,:scapi · ,g 29.936 D Flat landscape 01 0.07 210
Land~cap1~ 941 C Steep Landscape 01 0.075 7
0 0
0 0
0 0
0 0
0 0
0 0
0 0
0 0
0 0
0 0
0 0
BMP Tributary Area 60,352 Minimum BMP Size 1393
Proposed BMP Size• 1396 • Assumes standard configuration
Surface Ponding Depth 12.00 in
Bioretention Soil Media Depth 18.00 in
Filter Coarse 6.00 in
Gravel Storage Layer Depth 12 in
Underdrain Offset 3.0 in
Notes:
1. Runoff factors which are used for hydromodification management flow control (Table G.2·1) are different from the runoff factors used for pollutant control BMP sizing (Table 8.1-1). TabJe references are taken from the San Diego Region Model BMP Design Manua
Describe the BMP's in sufficient detail in your PDP SWQMP to demonstrate the area, volume, and other criteria can be met within the constraints of the site.
BM P's must be adapted and applied to the conditions specific to the devek>pment pro1ect such as unstabJe slopes or the lack of available head.
Designated Staff have final review and approval authority over the proJect design.
This BMP S111ng Spreadsheet has been updated in conformance with the San Diego Region Model BMP Design Manual, April 2018. For questions or concerns please contact the jurisdicttOn in which your project is located.
BMP Sizing Spreadsheet V3.0
Project Name: The Preserve at Quarry Creek Hydrologic Unit: Carlsbad
Project Applicant: El Saito Falls, LLC Rain Gauge: Oceanside
Jurisdiction: City of Carlsbad Total Project Area: 60,352
Parcel (APN): 167-040-49 Low Flow Threshold: 0.1Q2
BMP Name Biofiltration Basin BMP Type: Biofiltration
OMA Rain Gauge Pre-developed Condition Unit Runoff Ratio OMA Area (ac) Orifice Flow -%Q2 Orifice Area
Name Soil Type Slope (cfs/ac) (cfs) (in2)
Roofs/Hardscape Oceanside 0 Flat 0.571 0.313 0.018 0.25
Parking Lot Oceanside D Flat 0.571 0.363 0.021 0.30
Landscaping Oceanside D Flat 0.571 0.687 0.039 0.56
Landscaping Oceanside C Steep 0.499 0.022 0.001 0.02
3.75 0.079 1.13 1.20
Max Tot. Allowable Max Tot. Allowable Max Orifice Max Orifice Head Orifice Flow Orifice Area Diameter
(feet) (ds) (in2) (in)
0.074 0.079 1.13 1.200
Average outflow during Max Orifice Outflow Actual Orifice Area Selected
surface drawdown Orifice Diameter
(cfs) (cfs) (in2) (in)
Drawdown (Hrs) 5.3
f
I 0
~ ;;
"' ~ e ; :; ..
~ ii t
l
0. ~
i
i u
i 0
i ~
0.
~
0 5 10
Miles
EXPLANAT I O N
--Prec1p1tat1on Contours
Lake Vl.bhlford Basin
Ltndbergh Basin
Oceanside Basin
Brown /\Ni
Caldwell ~{\~@,~~·-~ I ' R AINFALL BASIN MAP
SAN DIEGO HMP
0.1Q2 C Steep 6 Oceanside 0.07 -O.lQ2 D Flat 3 Oceanside 0.07
O.lQ2 D Moderate 3 Oceanside 0.07 -O.lQ2 D Steep 3 Oceanside 0.07
o.1Q2 A Flat 18 Lake Wohlford 0.11
0.1Q2 .\ t-.loderate 18 Lake Wohlford 0.11
o.1Q2 A Steep 18 Lake Wohlford 0.105 -O.lQ2 B I ·lat 18 Lake Wohlford 0.09
o.1Q2 B Moderate 18 Lake Wohlford 0.085 -0.1Q2 B Steep 18 Lake Wohlford 0.085
O.lQ2 C Flat 6 Lake Wohlford 0.065
0.1Q2 C Moderate 6 Lake Wohlford 0.065
0.1Q2 C Steep 6 Lake Wohlford 0.065
O.lQ2 D l·ht 3 Lake Wohlford 0.06
0.1Q2 I) i'-lodcrate 3 Lake Wohlford 0.06 -O.lQ2 D Steep 3 Lake Wohlford 0.06
it Table G.2-5: Sizing Factors for Hydromodification Flow Control Biofiltration BMPs Designed Using Sizing
Factor Method
1 Lower Flow Threshold Soil Group Slope Rain Gauge A
0.1Q2 A Flat Lindbergh 0.32
0.1Q2 ,\ :\lodcratc Lindbergh 0.3
0.1Q2 ,\ Steep Lindbergh 0.285
0.1Q2 B Flat Lindbergh 0.105
0.1Q2 B Moderate Lindbergh 0.1
0.1Q2 B Steep J.indbergh 0.095
0.1Q2 C !·lat Lindbergh 0.055
0.1Q2 C Moderate Lindbergh 0.05
0.1Q2 C Steep Lindbergh 0.05
0.1Q2 D Flat Lindbergh 0.05
0.1Q2 D Moderate Lindbergh 0.05 -0.1Q2 D Steep l.indbcrgh 0.05
0.1Q2 t\ Flat Oceanside 0.15
l
I
1
7
-------7 0.1Q2 ,\ ~loderate Oc(.-ansidc 0.14
0.1Q2 t\ Steep Oceanside 0.135 -0.1Q2 B rlat Oc(.-ans1de 0.085
0.1Q2 R Mo derate Oceanside 0.085 -0.1Q2 B Steep Oc(.-ans1de 0.085
0.1Q2 C rlat Oceanside 0.o75 -0.1Q2 C l\loderarc Oc(.-ans1de 0.o75 ------
0.1Q2 C -Srccl! Oceanside (0.075
0.1Q2 I) !·lat Oceanside 0.07
0.1Q2 D Moderate Oceanside 0.07 -0.1Q2 D Steep Oc(.'"anside O.Q7
0.1Q 2 ,\ Flat Lake Wohlford 0.285 -0.1Q2 ,\ Moderate Lake Wohlford 0.275
0.1Q2 1\ Steep Lake Wohlford 0.27 -0.1Q2 R Flat I .ake Wo hlford 0.15
0.1Q2 B Moderare Lake Wohlford 0.145 --0.1Q2 B Srecp Lake Wohlford 0.145
0.1Q2 C Flat Lake Wohlford 0.o7 -0.1Q2 C Moderate Lake Wohlford 0.o7
0.1Q2 C Steep Lake Wohlford 0.o7 -0.1Q2 D Flat I .ake Wohlford 0.06
0.1Q2 D Moderate Lake Wohlford 0.06 -0.1Q2 D Stet:p Lake Wohlford 0.06
!::Table G.2-6: Sizing Factors for Hydromodification Flow Control Cistern Facilities Designed Using Sizing Factor 1-
i Method --~-.
Lower Flow Threshold Soil Group Slope Rain Gauge V
0.1Q2 A Flat Lindbergh 0.54
0.1Q2 ,\ Moderate l.indbcrgh 0.51
0.1Q2 A Steep l.indbergh 0.49
0.1Q2 B Flat
0.1Q2 R Moderate l.indbcrgh 0.18
0.1Q2 R Steep l.indbergh 0.1 8
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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:
D 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:
X 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)
X How to access the structural BMP(s) to inspect and perform maintenance
o 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)
o 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.)
X 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
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STRUCTURAL BMP MAINTENANCE
The project proposes a biofiltration basin for its structural pollutant and flow control BMP. The
biofiltration basin will contain an overflow catch basin set 12 inches above the basin floor to
convey the flow rates in excess of the water quality flows.
A biofiltration basin is a shallow, vegetated basin underlain by an engineered soil media and
gravel. Healthy plant and biological activity in the root zone maintain and renew the macro-pore
space in the soil and maximize plant uptake of pollutants and runoff. This keeps the BMP from
becoming clogged and allows more of the soil column to function as both a sponge (retaining
water) and a highly effective and self-maintaining biofilter .
The landscape maintenance staff shall inspect the biofiltration basin during routine weekly
landscaping maintenance visits. Access will be from the adjacent parking lot. The vegetation shall
be replanted, trimmed, pruned, and removed manually, as needed, to maintain proper coverage
and growth. The irrigation system shall be maintained, as needed. The drainage overflow from the
basin and interconnecting pipes shall be inspected monthly and after large storm events. Debris,
sediment, and other obstructions shall be removed immediately from the basin, its outlet, and the
interconnecting pipes. The infiltration rate shall be reviewed during storm events and the
underlying soil/gravel shall be replaced as needed to maintain the required drawdown time. The
removal can be performed with manual tools or a small bobcat type excavator.
Signs identifying the biofiltration basin and the need for preservation shall be installed in the basin.
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City standard Single Sheet BMP (SSBMP) Exhibit --[Use the City's standard Single Sheet BMP Plan.]
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BMP CONSTRUCTION AND INSPECTION NOTES:
THE £OW mLL VERIFY THAT PERMANENT BMPS ARE CONSTRUC7ED AND
OPERA nNG IN COMPUANCE mTH THE APPUCABLE REQUIREMENIS. PRIOR
TO OCCUPANCY THE £OW MUST PROVIDE:
1. PHOTOGRAPHS OF THE INSTALLA ll0/1 OF PERMANENT BMPS PRIOR
TO CO/ISTRUCll0/1, DURING CONSTRUCTION, AND AT RNAL
INSTALLA TIO/I.
2. A I\IT STAMPED LETTER VERIFYING THAT PERMANENT BMPS ARE
COIISTRUC1ED AND OPERA llNG PER THE REQUIREMENIS OF THE
APPROVED PLANS.
J. PHOTOGRAPHS TO VERIFY THAT PERMANENT WA 1E1? QUAUTY
TREATMENT SIGNAGE HAS BEEN INSTALLED.
PRIOR TO RELEASE OF SECURlnES, THE DEVELOPER IS RESPONSIBLE mR
ENSURING THE PERMANENT BMPS HA VE NOT BEEN REMOVED OR MOD/RED
BY THE NEW HOMEOWNER OR HOA mTHOUT THE APPROVAL OF mE CITY
ENGINEER.
12'' HOPE STORM DRAIN PIPE (TYP)
SEE PROFILE S01 SHEET ????
~,,,____ TYPE "F"
CATCH BASIN
SCALE : 1" = 20'
/
/->--PRESCHOOL BLDG-<
ROOKS 2424 INLET
.1-0-0
P" 1 01 ,o 136-
fl-"
(TYP)
PAD =
F.F. =
BLDG AREA
140.0
140.7
= 11930 S.F.
===
T0P=/40.0
FL=/38.74
/
DAlE
3
INITIAL
ENGINEER OF WORK
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GRAPHIC SCALE
20 0 10 20 40
~ .. !
' 1 INCH -20 FEET
BMPID# BMPTYPE SYMBOL CASQA NO.
TREATMENT CONTROL
PARTY RESPONSIBLE FOR MAINTENANCE:
NAME: EL SAL TO FALLS, LLC
ADDRESS: 211 MAIN STREET
VISTA, CA 92084 CONTACT: DAVID LOWEN
PHONE NO.: (760) 822-9347
PLAN PREPARED BY:
NAME: WAYNE W. CHANG
COMPANY: CHANG CONSULTANTS
ADDRESS: P.O. BOX 9496
RANCHO SANTA FE, CA 92067
PHONE NO.: (858) 692-0760
SIGNATURE
BMPNOTES: CERTIFICATION ____ _
1. THESE BMPS ARE MANDATORY TO BE INSTALLED PER MANUFACTURER'S
RECOMMENDATIONS ORTtlESE PLANS.
2. NO CHANGES TO THE PROPOSED BMPS ON THIS SHEET WITHOUT PRIOR
APPROVAL FROM THE CITY ENGINEER.
3. NO SUBSTITUTIONS TO THE MATERIAL OR TYPES OR PLANTING TYPES
WITHOUT PRIOR APPROVAL FROM THE CITY ENGINEER.
4. NO OCCUPANCY WILL BE GRANTED UNTIL THE CITY INSPECTION STAFF
HAS INSPECTED THIS PROJECT FOR APPROPRIATE BMP CONSTRUCTION
AND INSTALLATION.
5. REFER TO MAINTENANCE AGREEMENT DOCUMENT.
6. SEE PROJECT SWQMP FOR ADDITIONAL INFORMATION.
BMP TABLE
QUANTITY DRAWING NO. SHEET NO.(S) INSPECTION * MAINTENANCE *
FREQUENCY FREQUENCY
HYDROMODIFICATION & TREATMENT CONTROL
·(i) BIOFILTRA TION V // ,,I , TC-32 ... 1.il.96SF .. TBD 2 MONTHLY MONTHLY BAS!N -·'" .. ..
" ·..:: --'. ' ' ..
HYDROMODIFICATION
I I I
LOW IMPACT DESIGN (L.1.D.)
MANY ROOF DRAIN TO • SD-11 TBD TBD 2 ANNUALLY ANNUALLY PER PLAN LANDSCAPING
MANY LANDSCAPING I I SD-10 30,877 SF TBD 2 WEEKLY WEEKLY PER PLAN (PERVIOUS)
SOURCE CONTROL
0 TRASH ENCLOSURE i TRASH I SD-32 1 EA SDP 2 MONTHLY MONTHLY
(i)-@) STENCILS NO DUMPING SD-13 10 EA SDP 2 ANNUALLY ANNUALLY DRAINS TD OCEAN .
--r
I SH~ET I I SH~ETS I CITY OF CARLSBAD
ENGINEERING DEPARTMENT
SINGLE SHEET BMP SITE PLAN
CHILDREN'S PARADISE PRESCHOOLS
3335 MARRON ROAD
RECORD COPY
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PROJECT NO.
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DRAWING NO.
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DAlE INITIAL DAlE INITlAL
REVISION DESCRIPTION OTHER APPROVAL CITY APPROVAL INITIAL DAlE
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