cc 2026 AR 08/11 appeal of p24-0164, 552 w bobier dr project — Vista City Council, August 11, 2026 (part 3 of 5)

PH2
493 of 876

ENGINEER OF WORK CERTIFICATION STATEMENT
Preparer's Certification
I hereby declare that I am the Engineer in Responsible Charge of design of storm water best management practices (BMPs) for this project, and that I have exercised responsible charge over the design of the BMPs as defined in Section 6703 of the Business and Professions Code, and that the design is consistent with the PDP requirements of the City of Vista BMP Design Manual, which is a design manual for compliance with local City and regional MS4 Permit (California Regional Water Quality Control Board San Diego Region Order No. R9-2015- 0100) requirements for storm water management.

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 PDP SWQMP has been completed to the best of my ability and accurately reflects the project being proposed and the applicable BMPs proposed to minimize the potentially negative impacts of this project's land development activities on water quality. I understand and acknowledge that the plan check review of this PDP 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.

SWQMP PREPARED BY:

Michael D. Schweitzer
SWS Engineering, Inc.
1635 Lake San Marcos Drive, Suite 200
San Marcos, CA 92078
(760) 744-0011
[email protected]
R.C.E 59658
Exp. 12/31/2025
[INSERT STAMP IN SPACE BELOW]
R.C.E. 59658 Exp: 12/31/2026
Signature, PE License Number & Expiration Date
Michael D. Schweitzer
Print Name
3/17/2025
Date
08/11/2026

Page 3 of 38 ends

PH2
494 of 876

PROJECT OWNER CERTIFICATION STATEMENT
Owners Certification
This PDP SWQMP has been prepared for Michael D. Schweitzer by SWS Engineering, Inc.. The PDP SWQMP is intended to comply with the PDP requirements of the City of Vista BMP Design Manual, which is a design manual for compliance with local City and regional MS4 Permit (California Regional Water Quality Control Board San Diego Region Order No. R9-2015-0100) requirements for storm water management.

The undersigned, while it owns the subject property, is responsible for the implementation of the provisions of this plan. Once the undersigned transfers its interests in the property, its successor -in -interest shall bear the aforementioned responsibility to implement the best management practices (BMPs) described within this plan, including ensuring on -going operation and maintenance of structural BMPs. A signed copy of this document shall be available on the subject property into perpetuity.

OWNER DETAILS:

Michael D. Schweitzer
SWS Engineering, Inc.
1635 Lake San Marcos Drive, Suite 200
San Marcos, CA 92078
(760) 744-0011
[email protected]
Project Owner's Signature
Michael D. Schweitzer
Print Name
3/17/2025
Date
08/11/2026

Page 4 of 38 ends

PH2
495 of 876

CITY OF VISTA STAFF REVIEW
Reviewed and Approved:

City Staff Signature: Date:
08/11/2026

Page 5 of 38 ends

PH2
496 of 876

PAGE INTENTIONALLY BLANK
08/11/2026

Page 6 of 38 ends

PH2
497 of 876

PROJECT VICINITY MAP
Project Name: Waxwing Subdivision
Permit Application Number: P24-0164
Insert Project Vicinity Map Below:

SITE

W BOBIER DRIVE

NORTH AVE
c2
,.� POND
PLACE
WESTON
CIRCLE
08/11/2026

Page 7 of 38 ends

PH2
498 of 876

FORM 1- PROJECT CATEGORY DETERMINATION CHECKLIST
This form is used to assess stormwater BMP requirements applicable to the proposed project. The form is available as a stand-alone fillable checklist on the City's website and a completed copy must be included with the final SWQMP submitted to the City. The form is available at:
http://www.cityofvista.com/services/city-departments/community-development/building-planning permits-applications/land-development-autocad-templates/storm-water-forms 08/11/2026

Page 8 of 38 ends

PH2
499 of 876

Project ID: P24-0164

CHECKLIST FOR DETERMINATION OF PROJECT

CITY OF VISTA CATEGORY

C A L I F O R N I A
Project Name: Waxwing Subdivision
Project Location: 552 W Bobier Drive, Vista CA 92083

APPLICABILITY OF PERMANENT, POST -CONSTRUCTION STORMWATER BMP

REQUIREMENTS AND PROJECT TYPE DETERMINATION
Overview and Instructions
The City of Vista's (City's) Stormwater Management Program is regulated by the San Diego regional municipal stormwater permit (referred to as a Municipal Separate Storm Sewer System Permit). This permit requires that new development and redevelopment projects incorporate permanent stormwater Best Management Practices (BMPs) into the project design. The City of Vista's BMP Design Manual (formerly SUSMP Manual) discusses BMP requirements applicable to new development and redevelopment projects.

ALL STANDARD AND PRIORITY PROJECTS ARE REQUIRED TO INCORPORATE SITE DESIGN AND SOURCE CONTROL BMPS. Additional treatment control and hydromodification management BMP requirements apply to projects that meet specific criteria or thresholds. This checklist must be completed by the project applicant or proponent, and is used to determine if those additional BMPs are required.

Not all site improvements are considered "development projects" under the MS4 Permit.

Development projects are defined by the MS4 Permit as "construction, rehabilitation, redevelopment, or reconstruction of any public or private projects". Development projects are issued local permits to allow construction activities. To further clarify, this checklist applies only to new development or redevelopment activities and/or projects that have the potential to contact storm water and contribute an anthropogenic source of pollutants, or reduce the natural absorption and infiltration abilities of the land.

A project must be defined consistent with the California Environmental Quality Act (CEQA) definitions of "project."
CEQA requires that the project include "the whole of the action". "Whole of the Action" means the project may not be segmented or phased into small parts either onsite or offsite if the effect is to reduce the quantity of impervious area and fall below thresholds for applicability of storm water requirements. This requirement precludes "piece-mealing," which is the improper (and often artificial) separation of a project into smaller parts to avoid preparing Environmental Impact Report level documentation.

As indicated above, for the purposes of the BMP Design Manual, the "project" is the "whole of the action" which has the potential for adding or replacing or resulting in the addition or replacement of, roofs, pavement, or other impervious surfaces, thereby resulting in increased flows and storm water pollutants.

When defining the project, the following questions are considered:
• What are the project activities?
• Do they occur onsite or offsite?
• What are the limits of the project (project boundary)? • What is the whole of the action associated with the project (i.e. what is the total amount of new or 08/11/2026
PH2 500 of 876

replaced impervious area considering all of the collective project components through all phases of the project)?
• Are any facilities or agreements to build facilities offsite in conjunction with providing service to the project (street -widening, utilities)?
Responses to the checklist represent an initial assessment of the proposed project conditions and impacts.

City staff will confirm this checklist based on assessment of the development application and/or project plans. Results of the checklist will classify a project as one of the following: Priority Development Project, Standard Project, or Non -development Project.

If additional information is needed while completing this checklist, please refer to the City's BMP Design Manual. Alternatively, contact City Land Development staff.

This Form is divided into 4 sections:

1. Post -Construction Stormwater Requirement Exemptions

2. Priority Development Project Determination

3. Special Consideration for Redevelopment Projects (50 Percent Rule)

4. Final Project Determination
08/11/2026
PH2 501 of 876

SECTION 1- POST CONSTRUCTION STORMWATER

REQUIREMENT EXEMPTIONS
City of
BMP Design
Vista
Manual
This section will determine whether your project is exempt from post - construction BMP requirements and would be classified as a Non -Development Project. See section 1.3 of the City's BMP Design Manual for further discussion.

YES
NO
(a) Replacement of impervious surfaces that are part of a routine maintenance activity, such as (check yes if any apply):
(i) Replacing roof material on an existing building
(ii) Rebuilding a structure to original design after damage from earthquake, fire or similar disaster
(iii) Restoring pavement or other surface materials affected by trenches from utility work
(iv) Resurfacing existing roads and parking lots, including slurry, overlay and restriping
(v) Routine replacement of damaged pavement, including full depth replacement, if the sole purpose is to repair the damage (vi) Constructing new sidewalk, pedestrian ramps or bike lanes on existing roads (within existing street right-of-way)
(vii) Restoring a historic building to its original historic design (viii) Routine replacement of damaged pavement, such as pothole repair
.
❑
Note: Work that creates impervious surface outside of the existing impervious footprint is not considered routine maintenance.
(b) Repair or improvements to an existing building or structure that do not alter the size (check yes if any apply):
(i) Plumbing, electrical and HVAC work
(ii) Interior alterations including major interior remodels and tenant build - out within an existing commercial building
(iii) Exterior alterations that do not change the general dimensions and structural framing of the building (does not include building additions or projects where the existing building is demolished)
.
❑
If you answered YES to either category (a) or (b), your project is considered a Non -Development Project, and post construction BMP requirements do not apply. Please proceed to Section 4 and check the Non - Development Project box.

If you answered NO to category (a) and (b), please proceed to Section 2. 08/11/2026
PH2 502 of 876

SECTION 2 - PRIORITY DEVELOPMENT PROJECT

DETERMINATION
City of
BMP Design
Vista
Manual
This section determines whether your project is a Priority Development Project (PDP) or a Standard Project. See section 1.4 of the City's BMP Design Manual for further discussion. The following eight (8) types of projects are defined as PDPs:

YES
NO
(a) New development projects that create 10,000 square feet or more of impervious surfaces (collectively over the entire project site). This includes commercial, industrial, residential, mixed -use, and public development projects on public or private land.
.
❑
(b) Redevelopment projects that create and/or replace 5,000 square feet or more of impervious surface (collectively over the entire project site on an existing site of 10,000 square feet or more of impervious surfaces). This includes commercial, industrial, residential, mixed -use, and public development projects on public or private land.
❑
(c) New and redevelopment projects that create and/or replace 5,000 square feet or more of impervious surface (collectively over the entire project site), and support one or more of the following uses:
(i) Restaurants. This category is defined as a facility that sells prepared foods and drinks for consumption, including stationary lunch counters and refreshment stands selling prepared foods and drinks for immediate consumption (Standard Industrial Classification (SIC) code 5812). (ii) Hillside development projects. This category includes development on any natural slope that is twenty-five percent or greater. (iii) Parking lots. This category is defined as a land area or facility for the temporary parking or storage of motor vehicles used personally, for business, or for commerce.
(iv) Streets, roads, highways, freeways, and driveways. This category is defined as any paved impervious surface used for the transportation of automobiles, trucks, motorcycles, and other vehicles.
.
❑
08/11/2026
PH2 503 of 876

(d) New or redevelopment projects that create and/or replace 2,500 square feet or more of impervious surface (collectively over the entire project site), and discharge directly to an Environmentally Sensitive Area (ESA). "Discharging directly to" includes flow that is conveyed overland a distance of 200 feet or less from the project to the ESA, or conveyed in a pipe or open channel any distance as an isolated flow from the project to the ESA (i.e. not commingled with flows from adjacent lands).

Note: ESAs are areas that include but are not limited to all Clean Water Act Section 303(d) impaired water bodies; State Water Quality Protected Areas; water bodies designated with the RARE beneficial use by the State Water Board and San Diego Water Board; and any other equivalent environmentally sensitive areas which have been identified by the City.

For projects adjacent to an ESA, but not discharging to an ESA, the 2,500 sq-ft threshold does not apply as long as the project does not physically disturb the ESA and the ESA is upstream of the project.

There are no Areas of Special Biological Significance (ASBS) or State Water Quality Protected Areas in the City's jurisdiction. The ESAs within the City's boundaries which include 303(d) -listed impairments and RARE beneficial use designations are listed below:
• Agua Hedionda Creek
• Buena Creek
• Buena Vista Creek
• Loma Alta Creek
❑
(e) New development projects, or redevelopment projects that create and/or replace 5,000 square feet or more of impervious surface, that support one or more of the following uses:
.
❑
(i) Automotive repair shops. This category is defined as a facility that is categorized in any one of the following SIC codes: 5013, 5014, 5541, 7532-7534, or 7536-7539.
(ii) Retail gasoline outlets. This category includes Retail gasoline outlets that meet the following criteria: (a) 5,000 square feet or more or (b) a projected Average Daily Traffic of 100 or more vehicles per day. (f) New or redevelopment projects that result in the disturbance of one or more acres of land and are expected to generate pollutants post construction. This means any activity that moves soils or substantially alters the pre-existing vegetated or man-made cover of any land. This includes, but is not limited to the following:
.
❑
(i) Grading, digging, cutting, scraping, stockpiling, pavement removal, and exterior construction;
(ii) Substantial removal of vegetation where soils are disturbed including but not limited to removal by clearing or grubbing; or
(iii) Any activity which bares soil or rock or involves streambed alterations or the diversion or piping of any watercourse.

If you answered YES to any of the categories above (a -f), your project is considered a PDP. Please proceed to section 3 and check the Priority Development Project Box in Section 4.

If you answer NO to all categories, then your project is considered a Standard Project. Please proceed to Section 4 and check the Standard Project Box.
08/11/2026
PH2
504 of 876

SECTION 3 - SPECIAL CONSIDERATIONS FOR
REDEVELOPMENT PROJECTS (50 PERCENT RULE) j
L
City of vista
BMPDesignManual
This section determines additional considerations required for Redevelopment PDPs. See section 1.7 of the City's BMP Design Manual for further discussion.

YES
NO
WiII redevelopment result in the creation or replacement of impervious surface in an amount of more than 50 percent of the surface area of the previously existing development? See clarification on calculation of the ratio of impervious surface below.

These requirements for managing storm water on an entire redevelopment project site are commonly referred to as the "50 Percent Rule". For the purpose of calculating the ratio, the surface area of the previously existing development shall be the area of impervious surface within the previously existing ❑
development. The following steps shall be followed to estimate the area that requires treatment to satisfy the MS4 Permit requirements:

1. How much total impervious area currently exists on the site?

2. How much existing impervious area will be replaced with new impervious area?

3. How much new impervious area will be created in areas that are pervious in the existing condition?

4. Total created and/or replaced impervious surface = Step 2 + Step 3.

5. 50 Percent Rule Test: Is step 4 more than 50 Percent of Step 1? If yes, treat all impervious surface on the site (including existing impervious surface not being replaced or added). If no, then treat only Step 4 impervious surface and any area that comingles with created and/or replaced impervious surface area.

Note: Step 2 and Step 3 must not overlap, as it is fundamentally not possible for a given area to be both "replaced" and "created" at the same time. Also activities that occur as routine maintenance (see Section 1 of this form) shall not be included in Step 2 and Step 3 calculation.

For example, a 10,000 square foot development proposes replacement of 4,000 square feet of impervious area. The treated area is less than 50 percent of the total development area and only the 4,000 square foot area is required to be treated.

If you answered YES, then you must implement the PDP requirements for all impervious surfaces across the entire site. Please proceed to Section 4 and check the box under PDP indicating that the Project Is a Redevelopment Project Subject to the 50 Percent Rule.

If you answered NO, then you are only required to treat impervious surfaces that are replaced or created.

Please proceed to section 4 and check the box under PDP indicating this is Not a Redevelopment Project Subject to the 50 Percent Rule.
08/11/2026
PH2
505 of 876

ILB
SECTION 4 - FINAL PROJECT DETERMINATION City of Vista
MP Design Manual
BASED ON THE INFORMATION PROVIDED IN SECTIONS 1-3, THIS PROJECT IS DETERMINED TO BE A:

PRIORITY DEVELOPMENT PROJECT. PRIORITY REQUIREMENTS APPLY AND A STORM

WATER QUALITY MANAGEMENT PLAN (SWQMP) MUST BE SUBMITTED AT THE TIME OF APPLICATION.
❑ THIS IS A REDEVELOPMENT PROJECT SUBJECT TO THE 50 PERCENT RULE.

THIS IS NOT A REDEVELOPEMNT PROJECT SUBJECT TO THE 50 PERCENT RULE. ❑ STANDARD PROJECT. STANDARD REQUIREMENTS APPLY AND APPLICABLE SECTIONS

OF A STORM WATER QUALITY MANAGEMENT PLAN (SWQMP) MUST BE SUBMITTED AT THE TIME OF APPLICATION.
❑ NON DEVELOPMENT PROJECT.

Applicant Information and Signature Box
Address: APN(s)
SWS Engineering, Inc. 161-030-07
1635 Lake San Marcos Drive, Suite 200
Applicant Name:

Michael D. Schweitzer
Applicant Title:

CEO/President
Applicant Signature:

Date: 3/17/2025
City use only
Concur:

Yes
No
By:

Date:

Land Dev #:

Supporting discussion for this checklist, as well as BMP requirements for Priority Development Projects and Standard Projects, is provided in the City of Vista BMP Design Manual. 08/11/2026
PH2 506 of 876

FORM 2 - PROJECT OVERVIEW

Page 1 of 11 ends

Project Name
Waxwing Drive Subdivision
Project Address
552 W Bobier Drive, Vista, CA 92083
Assessor's Parcel Number(s) (APN(s))
161-030-07
Permit Application Number
P24-0164
Watershed (select one checkbox; use webpage
below to determine watershed)
rtments/com mu nity-develo oment/building- Diann' ng-
htt D:// www.cityofvista.com/services/city-de Da
permits-a D Dlications/land-develo Dment-autocad-tem plates/storm-water-forms San Luis Rey
X Lower San Luis Rey — Mission, 903.11
Carlsbad
X Loma Alta — Loma Alta, 904.10
❑ Buena Vista — El Salto, 904.21
X Buena Vista — Vista, 904.22
❑ Agua Hedionda — Los Monos, 904.31
❑ Agua Hedionda — Buena, 904.32
❑ San Marcos — Batiquitos, 904.51
Parcel Area
(total area of Assessor's Parcel(s) associated
with the project)

1.67 Acres ( 72,901 Square Feet)
Area to be Disturbed by the Project
(Project Area)
L70 Acres ( 74,242 Square Feet)
Project Proposed Impervious Area
(subset of Project Area)

0.67 Acres ( 42,160 Square Feet)
Project Proposed Pervious Area
(subset of Project Area)

0.74 Acres ( 32,083 Square Feet)
NOTE: Proposed Impervious Area + Proposed Pervious
Area = Area to be Disturbed by the Project.

This may be less than the Parcel Area.
2 Form 2, Page 2 of 11

Page 9 of 38 ends

08/11/2026
PH2 507 of 876

DESCRIPTION OF EXISTING SITE CONDITIONS
Current Status of the Site (select all that apply and describe below):
© Existing development
■ Previously graded but not built out
© Demolition completed without new construction
■ Agricultural or other non -impervious use
© Vacant, undeveloped/natural
Describe:

Parcel is located on 1.67 acres land currently being undeveloped. The site had an existing structure that has been demolished around 2008-2009 with no new development.

Existing Land Cover Includes (select all that apply and describe below):

1.49 64,801
© Vegetative Cover Acres ( Square Feet)
■ Non -Vegetated Pervious Areas Acres ( Square Feet)

0.18 8,100
© Impervious Areas Acres ( Square Feet)
Describe: The site had an existing structure that has been demolished around 2008-2009 with no new development.

Underlying Soil belongs to Hydrologic Soil Group (select all that apply):
■ N RCS Type A
■ N RCS Type B
■ N RCS Type C
© N RCS Type D
Approximate Depth to Groundwater (GW):
■ GW Depth 20 feet
Existing Natural Hydrologic Features (select all that apply and describe in next section):
■ Drainage ditch/Swale/Waterway
■ Seeps
■ Springs
■ Wetlands
© None

Page 10 of 38 ends

08/11/2026
PH2
508 of 876

Form 2, Page 3 of 11

DESCRIPTION OF EXISTING SITE DRAINAGE PATTERNS
How is storm water runoff conveyed from the site? At a minimum, this description should answer:

1. Is existing site drainage conveyance natural or improved storm drain (urbanized);

2. Is runoff from offsite conveyed through the site? If yes, quantify all offsite drainage areas, design flows, and locations where offsite flows enter the project site, and summarize how such flows are conveyed through the site;

3. Provide details regarding existing project site drainage conveyance network, including any existing storm drains, concrete channels, swales, detention facilities, storm water treatment facilities, natural or constructed channels; and

4. Identify all discharge locations from the existing project site along with a summary of conveyance system size and capacity for each of the discharge locations. Provide summary of the pre -project drainage areas and design flows to each of the existing runoff discharge locations.

Describe existing site drainage patterns:

The project is situated on one parcel of total area L67 ac undeveloped land. The site had an existing structure that has been demolished around 2008-2009 with no new development. The site slopes range from 2-25%. Runoff from Basin 1 of the project site will surface flow from the undisturbed natural terrain north onto West Bobier Drive, where it enters the existing storm drain system located on the west of the high point on Bobier that drains to Guajome Lake and ultimately into San Luis Rey River.

Basin 2 also drains into W Bobier Drive where it also enters into existing storm drain systems located on Moa Dr (east of Marabou Ln) and ultimately discharges into Buena Vista Creek. Runoff from basins (3-5) sheet flow along natural terrain in the southeasterly direction (not concentrated) towards the existing residential development on Waxwing Drive and Mynah Place which then discharge into existing storm drain systems located on Moa Dr (east of Marabou Ln) and ultimately into Buena Vista Creek.

Runoff from Basin 6 surface flows along the natural terrain that discharges offsite (adjacent property) in the southwesterly direction into existing concrete lined channel along the southern portion of the adjacent property then into public storm drain system and ultimately into Loam Alta Creek and finally into Pacific Ocean.

Majority of the site runoffs discharge into Loma Alta Creek and smaller area into Buena Vista Creek and ultimately into the Pacific Ocean. The small area draining toward Guajome Lake will be routed toward Buena Vista Creek in post condition.

The development of the site will not have any negative impact to the adjacent properties on the east, west and south as the development of the site will reduce the site runoff below the existing condition by constructing multiple basins to detain any excess water onsite. Also, much of the existing runoff to the east toward adjacent properties will be routed to the southwest in post condition. Rip rap will be added at the discharge point of each basin and POC points to reduce the runoff velocity of the discharge. The discharge points of the site will also be reduced.

There is no offsite run on in the existing condition. The improvement of the adjacent property on the west won't have any negative impact to our site as there is slope along site the project site drains away from out site and therefore there won't be any offsite draining to our project stie. (Refer to drainage report for more detail information).

Page 11 of 38 ends

08/11/2026
PH2
509 of 876

Form 2, Page 4 of 11

DESCRIPTION OF PROPOSED SITE DEVELOPMENT
Project Description / Proposed Land Use and/or Activities:

The proposed project site consists of 15 townhomes (two-story structure), patio (future contingency) with associated driveway, private street, utilities, and other associated improvements and onsite treatment basins as well as the Tree -Well (to site front improvement area). The project site is one parcel with a total area of 1.67 ac that is located south of West Bobier Drive and at the north end of the current extent of Waxwing Drive in the City of Vista, California. The site is located on R -1-B (7.5) Single -Family Residential zone and is currently undeveloped land. The proposed land use for this project is MDR (Medium Density Residential). (Refer to drainage report for more detail information).

List/describe proposed impervious features of the project (e.g., buildings, roadways, parking lots, courtyards, athletic courts, other impervious features):
15 Single family residential units, patio (future contingency), drive lanes, associated driveways, private street,
List/describe proposed pervious features of the project (e.g., landscape areas):

Landscape Areas
Does the project include grading and changes to site topography? ® Yes
■ No
Describe: The proposed site will be entirely regraded to maintain as close to the original drainage discharge locations, and with associated cut and fill to balance earth work and reduce the export and import.

Page 12 of 38 ends

08/11/2026
PH2
510 of 876

Form 2, Page 5 of 11

DESCRIPTION OF PROPOSED SITE DRAINAGE PATTERNS
Does the project include changes to site drainage (e.g., installation of new storm water conveyance systems)?
❑X Yes
❑ No
If yes, provide details regarding the proposed project site drainage conveyance network, including storm drains, concrete channels, swales, detention facilities, storm water treatment facilities, natural or constructed channels, and the method for conveying offsite flows through or around the proposed project site. Identify all discharge locations from the proposed project site along with a summary of the conveyance system size and capacity for each of the discharge locations. Provide a summary of pre- and post -project drainage areas and design flows to each of the runoff discharge locations. Reference the drainage study for detailed calculations.

Describe proposed site drainage patterns:

The proposed site is undeveloped land that consists of 15 townhomes (two-story structure) with associated driveway, private street, utilities, and other associated improvements and treatment basins.

The project site is one parcel with a total area of 1.67 ac that is located south of West Bobier Drive, and on the north end of the existing Waxwing Drive within the City of Vista, California.

The proposed site drainage from Basins 1 and 3 will surface flow via proposed site roofs, hardscape, and curb -gutter into a proposed treatment basins located in the north and northeast portion of the site prior to discharging into W Bobier Drive east of high point. Basin 2 that has small improvement will also surface flow in northerly direction into W Bobier Drive east of high point. Basins (4.1, 4.2, 4.3) which are landscape area will sheet flow offsite in the easterly direction as it does in the existing condition with very minor runoffs less/equal than 0.1 cfs. All the runoff from basins (1-4) ultimately discharge into existing storm drain systems located on Moa Dr (east of Marabou Ln) similar to the existing condition prior to discharging in Buena Vista Creek.

Basin 5 will sheet flow in the easterly direction into proposed treatment basin and then routed offsite via proposed storm drain system into southwest corner of the site. Basins 6 and 7 will discharge via curb gutter and catch basins into proposed treatment basins located on the west north and south side of the project site prior to discharging toward southwest offsite corner of the site via proposed storm drain systems. All the discharge runoff from basins (5-8) will discharge into existing lined channel along southern portion of the adjacent property on the west via concrete ditch that is built along eastside of the adjacent property (after the adjacent property development is completed). Basin 8 is a small landscape area that will sheet flow offsite on the westerly direction.

Majority of the site 1.24 ac (basins 5-8) runoffs will discharge into Loma Alta Creek and smaller area on the east portion of the site 0.43 ac (basins 1-4) into Buena Vista Creek via sheet flow and existing public storm drain systems and ultimately discharge into the Pacific Ocean.

Page 13 of 38 ends

08/11/2026
PH2
511 of 876

The discharging runoff from basins 1-3 into W Babier Drive, will confluence with the runoff from basins (4.1, 4.2, 4.3) at Mynah PI and Marabou Ln which ultimately discharge in existing storm drain systems located on Moa Dr (east of Marabou Ln).

The proposed project site will have an increase in flow compared to the existing condition due to the coefficient C, diversion and time of concentration. The excess Q will be detained by multiple proposed biofiltration basins to reduce the Q below the existing condition at the two POCs, one from basins (1-4) at the confluence point of Mynah PI and Marabou Ln and the second at the southwest corner of the site from basins (5-8).

There is no offsite run-on in the post -condition. The improvement of the adjacent property on the west won't have any negative impact to our site as there is slope along site the project site drains away from our site and therefore there won't be any offsite draining to our project site. The development of our project site won't have any negative impact to the adjacent property since the excess runoff compared to existing condition will be detained onsite. The attenuated runoff will discharge into existing lined channel along the southern portion of the adjacent property via concrete ditch that is built along eastside of the adjacent property (after the property development is completed). (Refer to drainage report for more detail information).

Page 14 of 38 ends

08/11/2026
PH2 512 of 876

Form 2, Page 6 of 11

POTENTIAL POLLUTANT SOURCE AREAS
Identify whether any of the following features, activities, and/or pollutant source areas will be present.

Select all Pollutant Source Areas that apply and include them on the DMA Exhibit. Source control BMPs must be identified for each of these areas in Form 3 of this SWQMP:

O On -site storm drain inlets
❑ Sump pumps or French drains
❑ Interior or sub -surface parking garages
O Need for future indoor & structural pest control
O Landscape/outdoor pesticide use
❑ Pools, spas, ponds, decorative fountains, or other water features ❑ Food preparation and/or service
O Refuse/trash collection areas
❑ Industrial processes
❑ Outdoor storage of equipment, chemicals, or materials ❑ Vehicle and equipment cleaning
❑ Vehicle/equipment repair and maintenance
❑ Fuel dispensing areas
❑ Loading docks
O Fire sprinkler test and relief point
O Miscellaneous drain or wash down areas
O Plazas, sidewalks, and parking lots
Describe: the pollutant source area (impervious) are the roofs, patio and decks, downspouts, Trash areas, driveways, private street.

The anticipated pollutant for attached residential development are: sediment, nutrients, trash and debris, potential Oxygen demanding substances, potential oil ang grease, potential bacteria & viruses, pesticides

Page 15 of 38 ends

08/11/2026
PH2
513 of 876

Form 2, Page 7 of 11

IDENTIFICATION AND NARRATIVE OF RECEIVING WATER AND POLLUTANTS OF CONCERN Describe flow path of storm water from the project site discharge location(s), through urban storm conveyance systems as applicable, to receiving creeks, rivers, and lagoons as applicable, and ultimate discharge to the Pacific Ocean (or bay, lagoon, lake or reservoir, as applicable):

The site flow will discharge from the site into Loma Alta Creek, then into Loma Alta Slough, and ultimately into the Pacific Ocean.

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 and/or Highest Priority Pollutants from the WQIP for the impaired water bodies:
303(d) Impaired Water Body
Pollutant(s)/Stressor(s)
TMDLs / WQIP Highest Priority Pollutant
Loma Alta Creek (904.10)
Phosphorus, Selenium, Toxicity,
Pyrethroids, Bifenthrin,
Cyfluthrin, Cyhalothrin, Lambda,
Benthic Community Effects,
Indicator Bacteria, Nitrogen
Phosphorus (Alternative TMDL —
Addressed By Regional MS4 Permit Per
Carlsbad WMA WQIP)
Loma Alta Slough (904.10
Eutrophic, Indicator Bacteria
Phosphorus (Alternative TMDL —
Addressed By Regional MS4 Permit Per
Carlsbad WMA WQIP)
Pacific Ocean Shoreline, Loma
Alta HAS, at Loma Alta Creek
Mouth (904.10)
Indicator Bacteria, Trash
Phosphorus (Alternative TMDL —
Addressed By Regional MS4 Permit Per
Carlsbad WMA WQIP)
Buena Vista Creek (904.21)
Phosphorus, Selenium, Total
Dissolved Solids, Toxicity,
Bifenthrin, Cyfluthrin, Benthic
Community Effects, Indicator
Bacteria, Nitrogen, Pyrethroids,
Cypermethrin
N/A (No TMDLs or WQIP HPWQCs)
Buena Vista Lagoon (904.21)
Indicator Bacteria, Nutrients,
Sedimentation/Siltation, Toxicity
N/A (No TMDLs or WQIP HPWQCs)
Pacific Ocean Shoreline, Buena
Vista Creek HA, at Buena Vista
Lagoon Oulter (904.21)
N/A
N/A (No TMDLs or WQIP HPWQCs)
Guajome Lake
Eutrophic
Indicator Bacteria
Lower San Luis Rey River
Pyrethroids, Bifenthrin, Benthic
Community Effects, Chloride,
Oxygen, Dissolved, Phosphorus,
Total Dissolved Solids, Toxicity,
Nitrogen
Indicator Bacteria

Page 16 of 38 ends

08/11/2026
PH2
514 of 876

Pacific Ocean Shoreline at San
Luis Rey River
Indicator Bacteria
Indicator Bacteria
Identification of Project Site Pollutants* N/A Site is not participating in an Alternative Compliance *Identification of project site pollutants is only required if flow-thru treatment BMPs are implemented onsite in lieu of retention or biofiltration BMPs (note the project must also participate in an alternative compliance program unless prior lawful approval to meet earlier PDP requirements is demonstrated) Identify pollutants expected from the project site based on all proposed use(s) of the site (see BMP Design Manual Appendix B.6):

Pollutant
Not Applicable to the
Project Site
Expected from the
Project Site
Also a Receiving Water Pollutant
of Concern
Sediment
Nutrients
Heavy Metals
Organic Compounds
Trash & Debris
Oxygen Demanding
Substances
❑
❑
❑
Oil & Grease
❑
Bacteria & Viruses
Pesticides

Page 17 of 38 ends

08/11/2026
PH2 515 of 876

Form 2, Page 8 of 11

HYDROMODIFICATION MANAGEMENT REQUIREMENTS
Do hydromodification management requirements apply (see Section L6 of the BMP Design Manual; select one box and describe below)?
❑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.
❑ 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.

Describe:

There are two POCs on site, POC-1 located on the northeast for DMA (1-4), POC-2 located on the southwest corner of the site where DMAs 5-8 will discharge into from multiple biofiltration basins into existing storm drain systems. DMA 4 and 8 are self -mitigating areas (used in the SWMM analysis) sheet flow offsite (not concentrated) as they do in the existing condition.

Page 18 of 38 ends

08/11/2026
PH2 516 of 876

Form 2, Page 9 of 11

CRITICAL COARSE SEDIMENT YIELD AREAS
*This section only required if hydromodification management requirements apply Based on the maps provided within the WMAA, do potential critical coarse sediment yield areas exist within the project drainage boundaries (select all that apply and describe below)? Additional signed and stamped reports must be provided to document any exemption from coarse sediment yield requirements.
■ Yes
© 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?
■ 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 ■ No optional analyses performed, the project will avoid critical coarse sediment yield areas identified based on WMAA maps
If optional analyses were performed, what is the final result? ■ No critical coarse sediment yield areas to be protected based on verification of GLUs onsite ■ Critical coarse sediment yield areas exist but additional analysis has determined that protection is not required. Documentation attached in Attachment 2.B of the SWAMP. ■ 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 SWAMP Exhibit.

Describe:

Page 19 of 38 ends

08/11/2026
PH2 517 of 876

Form 2, Page 10 of 11

FLOW CONTROL FOR POST -PROJECT RUNOFF
*This section only required if hydromodification management requirements apply List and describe point(s) of compliance for hydromodification management flow control (see Section

6.3.1). Identify each point of compliance for flow control on the Hydromodification Management Exhibit in Attachment 2A.

Has a geomorphic assessment been performed for the receiving channel(s)? © No, the low flow threshold is 0.1Q2 (default low flow threshold) ■ Yes, the result is the low flow threshold is 0.1Q2
■ Yes, the result is the low flow threshold is 0.3Q2
■ Yes, the result is the low flow threshold is 0.5Q2
If a geomorphic assessment has been performed, provide the report.

Discussion / Additional Information: (optional)

Page 20 of 38 ends

08/11/2026
PH2 518 of 876

Form 2, Page 11 of 11

OTHER SITE REQUIREMENTS AND CONSTRAINTS
When applicable, list other site requirements or constraints that will influence storm water management design, such as zoning requirements including setbacks and open space, or local codes governing minimum street width, sidewalk construction, allowable pavement types, and drainage requirements.

Optional Additional Information or Continuation of Previous Sections As Needed This space provided for additional information or continuation of information from previous sections as needed.

There is a small site front improvement that will be treated via proposed Tree -Well. This proposed Tree - Well will treat any site frontage improvement and portion of the site front street in exchange for the DMA -2.1 that cannot be treated.

Page 21 of 38 ends

08/11/2026
PH2 519 of 876

FORM 3 - SOURCE CONTROL BMPS FOR ALL DEVELOPMENT PROJECTS

Page 1 of 4 ends

PROJECT IDENTIFICATION & SOURCE CONTROLS
Project Name: Waxwing Subdivision
Permit Application Number: P24-0164
All development projects must implement source control BMPs SC -1 through SC -6, unless justification is provided by qualified design professional See Chapter 4 and Appendix E of the Model BMP Design Manual for information to implement source control BMPs shown in this checklist.

Answer each category below pursuant to the following, and provide description. • "Yes" means the project will implement the source control BMP as described in Chapter 4 and/or Appendix E of the Model BMP Design Manual.
• "No" means the BMP is applicable to the project but it is not feasible to implement. • "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).

Source Control Requirement
Applied?
SC -1 Prevention of Illicit Discharges into the MS4
❑ No
❑ N/A
X Yes
Describe how source control will be implemented, or justify if not feasible:

Providing educational material to homeowners "as a suit of housekeeping BMP" to effectively eliminate discharges of non -storm water into the storm drain system which would include effective irrigation, dispersion of non -storm water discharges into landscaping for infiltration, and controlling wash water from vehicle washing. Appropriate signage will be provided on storm inlets to discourage the deposition of any illicit materials.

SC -2 Storm Drain Stenciling or Signage
❑ No
❑ N/A
X Yes
Describe how source control will be implemented, or justify if not feasible:

Appropriate signage will be provided on each storm inlet. Signage will be maintained or replaced as needed.

SC -3 Protect Outdoor Materials Storage Areas from Rainfall, Run -On, Runoff, and Wind Dispersal
❑ Yes
❑ No
X N/A
Describe how source control will be implemented, or justify if not feasible:

No outdoor material storage area is proposed
SC -4 Protect Materials Stored in Outdoor Work Areas from Rainfall, Run -On, Runoff, and Wind Dispersal
❑ Yes
❑ No
X N/A
Describe how source control will be implemented, or justify if not feasible:

No outdoor work area is proposed

Page 22 of 38 ends

08/11/2026
PH2
520 of 876

Form 3, Page 2 of 4
Source Control Requirement
Applied?
SC -5 Protect Trash Storage Areas from Rainfall, Run -On, Runoff, and Wind Dispersal
❑ Yes
❑ No
X N/A
Describe how source control will be implemented, or justify if not feasible:

No centralized trash storage areas are proposed
SC -6 Additional BMPs Based on Potential Sources of Runoff Pollutants (must answer for each source listed below)
Applied?
a. On -site storm drain inlets
❑ No
❑ N/A
X Yes
Describe how source control will be implemented, or justify if not feasible:

Appropriate signage will be implemented on each storm drain inlet. Signage will be maintained and replaced as needed.
b. Sump pumps or French drains
❑ Yes
❑ No
X N/A
Describe how source control will be implemented, or justify if not feasible:

No sump pumps or French drains proposed.
c. Interior or sub -surface parking garages
❑ Yes
❑ No
X N/A
Describe how source control will be implemented, or justify if not feasible:

No interior or sub -surface parking garages proposed.
d. Need for future indoor & structural pest control
❑ No
N/A
X Yes
Describe how source control will be implemented, or justify if not feasible:

Building design will include features such as weather stripping that discourage entry of pests. e. Landscape/outdoor pesticide use
❑ No
❑ N/A
X Yes
Describe how source control will be implemented, or justify if not feasible:

Usage of pest -resisting plants in landscape will be used, pesticide sued will be kept to a minimum.

Page 23 of 38 ends

08/11/2026
PH2 521 of 876

Form 3, Page 3 of 4
Source Control Requirement
Applied?
f. Pools, spas, ponds, decorative fountains, or other water features ❑ Yes
❑ No
X N/A
Describe how source control will be implemented, or justify if not feasible:

No pools, spas, ponds, decorative fountains, or other water features are proposed. g. Food preparation and/or service
❑ Yes
❑ No
X N/A
Describe how source control will be implemented, or justify if not feasible:

No food preparation/service will be implemented on -site. h. Refuse/trash collection areas
❑ Yes
❑ No
X N/A
Describe how source control will be implemented, or justify if not feasible:

No centralized trash storage areas are proposed
i. Industrial processes
❑ Yes
❑ No
X N/A
Describe how source control will be implemented, or justify if not feasible:

No industrial processes will be implemented on -site.
j. Outdoor storage of equipment, chemicals, or materials ❑ Yes
❑ No
X N/A
Describe how source control will be implemented, or justify if not feasible:

No outdoor storage areas are proposed.
k. Vehicle and equipment cleaning
❑ Yes
❑ No
X N/A
Describe how source control will be implemented, or justify if not feasible:

No vehicle and equipment cleaning areas are proposed.

I. Vehicle/equipment repair and maintenance
❑ Yes
❑ No
X N/A
Describe how source control will be implemented, or justify if not feasible:

No vehicle/equipment repair or maintenance areas are proposed. m. Fuel dispensing areas
❑ Yes
❑ No
X N/A
Describe how source control will be implemented, or justify if not feasible:

No fuel dispensing areas are proposed.

Page 24 of 38 ends

08/11/2026
PH2
522 of 876

Form 3, Page 4 of 4
n. Loading docks
❑ Yes
❑ No
X N/A
Describe how source control will be implemented, or justify if not feasible:

No loading docks are proposed.
o. Fire sprinkler test water and relief point
❑ Yes
❑ No
X N/A
Describe how source control will be implemented, or justify if not feasible:
p. Miscellaneous drain or wash down areas
n Yes
❑ No
❑ N/A
Describe how source control will be implemented, or justify if not feasible:

Roofing, gutters, and trim of proposed buildings will not be made of copper or any other unprotected metal that may leach into runoff.
q. Plaza, sidewalks, parking lots
❑ No
❑ N/A
X Yes
Describe how source control will be implemented, or justify if not feasible:

Sidewalks shall be swept regularly by HOA to prevent the accumulation of litter and debris. Washing will be kept to a minimum, and debris from occasional washing will be collected to prevent entry into storm drain system.

Discussion / justification if SC -6 not implemented. Clearly identify which sources of runoff pollutants are discussed. Justification must be provided for all "No" answers shown above.

Page 25 of 38 ends

08/11/2026
PH2 523 of 876

FORM 4 - SITE DESIGN BMPS FOR ALL DEVELOPMENT PROJECTS

Page 1 of 2 ends

PROJECT IDENTIFICATION
Project Name: Waxwing Subdivision
Permit Application Number: P24-0164
All development projects must implement site design BMPs SD -1 through SD -8, unless justification is provided by qualified design professional. See Chapter 4 and Appendix E of the Model BMP Design Manual for information to implement site design BMPs shown in this checklist.

Answer each category below pursuant to the following, and provide description. • "Yes" means the project will implement the site design BMP as described in Chapter 4 and/or Appendix E of the Model BMP Design Manual.
• "No" means the BMP is applicable to the project but it is not feasible to implement. • "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 site has no existing natural areas to conserve).

Site Design Requirement
Applied?
SD -1 Maintain Natural Drainage Pathways and Hydrologic Features ❑
Yes
❑
No
X
N/A
Describe how site design will be implemented, or justify if not feasible:

The site will be entirely graded.

SD -2 Conserve Natural Areas, Soils, and Vegetation
X Yes
No
N/A
Describe how site design will be implemented, or justify if not feasible:

Portion of the site on the north won't be graded (in DMA -2.1).

SD -3 Minimize Impervious Area
❑ No
❑ N/A
X Yes
Describe how site design will be implemented, or justify if not feasible:

Impervious footprint minimized in plan. North, south and east portion of the site would be landscape to minimize imperviousness on the site and also east side of the site would function as self -mitigating areas.

SD -4 Minimize Soil Compaction
❑ No
❑ N/A
X Yes
Describe how site design will be implemented, or justify if not feasible:

Soil compaction will be minimized in natural landscape areas. Disturbed slope soils will also be amended and aerated.

Page 26 of 38 ends

08/11/2026
PH2
524 of 876

Form 4, Page 2 of 2
SD -5 Impervious Area Dispersion
❑ No
❑ N/A
X Yes
Describe how site design will be implemented, or justify if not feasible:

Where feasible landscape will effectively receive, infiltrate and treat runoff from impervious areas prior to discharging into series of biofiltration basins. Roof drains will be directed to landscape areas where feasible prior to discharging to treatment basins and then into storm water conveyance systems.

SD -6 Runoff Collection
❑ Yes
❑ N/A
X No
Describe how site design will be implemented, or justify if not feasible:

Green Roofs: Requirement of more than 90% is the roof surface being vegetated is infeasible due to building design. However, the building design will include a light-colored roof to reduce the heat island effect, similar to a green roof.

Permeable Pavement: Due to the constrained nature of the site, permeable pavement cannot be provided in appreciable sizes without disturbing underground utilities. Site landscape will be used instead to provide percolation of storm water into the subsurface.

Rain Barrels: County requirements per fact sheet SD -E include landscape areas that are greater than 30 percent of the project footprint, which this site is not.

SD -7 Landscaping with Native or Drought Tolerant Species ❑ No
❑ N/A
X Yes
Describe how site design will be implemented, or justify if not feasible:

Native/drought tolerant plants will be implemented.

SD -8 Harvest and Use of Precipitation
N/A
■Yes
X No
Describe how site design will be implemented, or justify if not feasible:

County requirements per fact sheet SD -E include landscape areas that are greater than 30 percent of the project footprint, which this site is not. Due to this harvest and use calculations were completed and it was determined infeasible. See calculations on Worksheet B.3-1.

Per the site design for this project, series of biofiltration basins area proposed throughout the site to reduce the site required DCV.

Page 27 of 38 ends

08/11/2026
PH2 525 of 876

FORM 5 - STRUCTURAL POLLUTANT CONTROL AND

HYDROMODIFICATION MANAGEMENT BMPS

PROJECT IDENTIFICATION
Project Name: Waxwing Subdivision
Permit Application Number: P24-0164
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 local jurisdiction at the completion of construction. This may include requiring the project owner or project owner's representative and engineer of record 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 local jurisdiction 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 (page 3 of this form) 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 BMP selected). For projects requiring hydromodification flow control BMPs, indicate whether pollutant control and flow control BMPs are integrated or separate structures.

Note: Each structural pollutant control and hydromodification management BMP must be clearly identified on a site map (Attachment la), and described in supporting table (Attachment 1B). -The area to be disturbed was measured and a DCV was calculated for DMAs 1, 3, 5, 6, 7 per attached DMA map.
-Harvest and use was not deemed feasible per worksheet B.3-1. -Site soil and geologic conditions dictate that the infiltration (Average 0.09 in/hr with Factor of Safety 2) is not possible at this site (Please see the infiltration testing report prepared by CW Soils, dated April 25, 2024.
-The project will involve construction of five biofiltration basins along the southern, norther, eastern boundary of the parcel in DMAs (1, 3, 5, 6, 7). The site runoffs from rooftops and private street will discharge into biofiltration basins via surface flow, curb gutter, and storm drain systems. -Design of the biofiltration basins will account for the necessary treatment and hydromodification requirements and for the 100 -year storm event.
-The DMAs (1, 3, 5, 6, 7) containing the treatment BMPs are of impervious area, with flows ultimately discharging into Loma Alta Creek ang Buena Vista Creek.

Tree -Well will be provided to treat the site front improvement and portion of the site front street to swap for the DMA -2.1 that cannot be treated.

Page 28 of 38 ends

08/11/2026
PH2
526 of 876

FORM 6 - STORMWATER BMP MAINTENANCE MECHANISM

PROJECT IDENTIFICATION
Project Name: Waxwing Drive Subdivision
Permit Application Number
Maintenance Requirements: P24-0164
A stormwater structural BMP operations and maintenance plan must be prepared for PDPs. A template plan is available at:
htt D:// www.cityofvista.com/services/city-de Dartments/community-develo Dment/buildi ng-Dlanning- Dermits-applications/land-development-autocad-templates/storm-water-forms Has a stormwater structural BMP operations and maintenance plan been prepared? X Yes, included with Attachment 3A
❑ No — To be provided at final engineering
[INSERT PLAN NAME]
[INSERT PLAN DATE]
[INSERT PREPARER'S NAME]
[INSERT PREPARER'S TITLE/COMPANY]
All projects are required to maintain designed functionality of structural BMPs in perpetuity. Privately - owned projects must record a Storm Drain Maintenance Agreement with the County of San Diego Assessor's Office. A template Storm Drain Maintenance Agreement is available at:
htt D:// www.cityofvista.com/services/city-de Dartments/community-develo Dment/building-Dlanning- permits-a o 3lications/land-develo 3ment-autocad-tem plates/storm-water-forms Has a Storm Drain Maintenance Agreement been submitted to the County? ❑ Yes, copy included with Attachment 3B
X No — To be provided at final engineering
❑ Not Applicable (e.g., city -owned property/project)

Page 29 of 38 ends

08/11/2026
PH2 527 of 876

ATTACHMENT 1- POLLUTANT CONTROLS: SUPPORT DOCUMENT AND

CHECKLIST
Each of the attachments indicated below should be considered for inclusion with the SWQMP. Use this checklist to indicate which attachments are included behind this coversheet.

Attachment
Sequence
Contents
Checklist
Attachment 1A
Drainage Management Area (DMA)
Exhibit
See DMA Exhibit Checklist on next page.

X Included
Attachment 1B
Tabular Summary of DMAs Showing
DMA ID matching DMA Exhibit, DMA
Area, DMA Type, and BMPs*
*Provide table in this Attachment OR on
DMA Exhibit in Attachment 1A
M Included on DMA Exhibit in Attachment 1A
X Included as Attachment 1B
Attachment 1C
Harvest and Use Feasibility Screening
Checklist (Worksheet B.3-1)
Refer to Appendix B.3-1 of the BMP
Design Manual.

X Included
Not included because the entire project
will use Infiltration BMPs
Attachment 1D
Categorization of Infiltration Feasibility
Condition (Worksheet C.4-1)
Refer to Appendices C and D of the BMP
Design Manual.

X Included
U Not included because the entire project
will use Harvest and Use BMPs
Attachment 1E
Pollutant Control BMP Design
Worksheets and Calculations
Refer to Appendices B and E of the BMP
Design Manual for structural pollutant
control BMP design guidelines
X Included

Page 30 of 38 ends

08/11/2026
PH2 528 of 876

ATTACHMENT 1A - DMA EXHIBIT CHECKLIST
For Attachment 1A, provide map(s) for the project site, titled "DMA Exhibit." The checklist below identifies minimum elements that must be included with the DMA Exhibit.

Z Underlying hydrologic soil group
Z Approximate depth to groundwater
O Existing natural hydrologic features (watercourses, seeps, springs, wetlands, etc.) O Critical coarse sediment yield areas to be protected
O Existing topography and impervious areas
O Existing and proposed site drainage network and storm drain structures O Proposed connections to offsite drainage
O Proposed demolition
O Proposed grading
O Proposed impervious features
O Proposed design features and surface treatments used to minimize imperviousness O Drainage management area (DMA) boundaries
Z DMA identification numbers (DMA ID)
O DMA areas (square footage or acreage)
O DMA type (Drains to BMP, Self -mitigating, De Minimis, or Self -retaining) O Potential pollutant source areas and corresponding required source controls (see Form 2 and Form 3 of SWQMP, BMP Design Manual Chapter 4 and Appendix E.1) O Proposed Structural BMPs (see Form 5 of SWAMP)
08/11/2026

Page 31 of 38 ends

PH2
529 of 876

ATTACHMENT 1A & 1B
08/11/2026
PH2 530 of 876

LEGEND
OD
N
N
IM P -5 (BF -1) -
BOTTOM A = 141 SF/)
TYP. SD -
MP!
DMA'
(SELFM ITIGATIN0.)
- - 1,427 SIF
I. o
TYP. 50-Y
H i
IMP43 -i)
BO TTO M A=1.4a SF

AQUASAVE STORAGE
TYP. 50-4
00 —
PO C-2
0 CA)
— -1: (DMAs 1-3) DRAIN INTO BUENA VISTA CREEK
DMA -4 ALSO DRAINS INTO BUENA VISTA CREEK
DMAs (1-4) CONFLUENCE AT MYNAH PL AND MARABOU LN
— �-2 (DMAs 5-7) DRAIN INTO LOMA ALTA CREEK
DMA -8 ALSO DRAINS INTO LOMA ALSO CREEK
I MP -2 (SO -1)
TREEWELL: 5 .s W x 29' L TIP .

I MP -1 (BF1)r
DMA -2.3 (1,341 SF BOTTOM A= 121 SF
NEW SIDEWALK mom
_ ^..-=
, . 5 )•E
DMA -22 (SWAP)
1950 SF
45 F.F. 457.39
FF 459.19
0A A=7
33 809 SF
I F.F. 480.3
-D I' iP LS 278
V!
F. F. 443. 48
DMA=2I (SW AP),
.4,101 SF' • -• .
11,505
(462 .6 FDA
TYP. ❑
POC-1
l I/ SO P''_SPR
IE 45616'
PP . A
IMP -3 (BF -1)
BOTTOM A = 218 SF
TYP . SD -7
TYP. SO -4
TYP. 0
PP. SD -4
TYP . D
TIP. SO -7
r2 FD) NIAI • IMP -4 (BF -1)
9;11' 1 BOTTOM A=3185F
(460 1 Fr,),
T1P. 0
DMA -4
(SELF MITI GATING)
3,889 SF
TYP. 50-4
Q002

1.5" IP OPEN
20 10 0 20 40

SCALE IN FEET

GRAPHIC SCALE
> 9'

DMA BOUNDARY

SOIL TYPE

GROUNDWATER TABLE

FLOW DIRECTION

LANDSCAPE AREA

BIOFILTRATION AREA

IMPERVIOUS AREA (BLDG)

IMPERVIOUS AREA (CONCRETE)

IMPERVIOUS AREA (AC)

AREA THAT CAN NOT BE TREATED ONSITE (SWAP AREA)

STREET UNDISTURBED AREA (SWAP AREA)
TABULAR SUMMARY OF DMAs
DMA
IMP #
AREA
(SF)

IMPERVIOUS

AREA (SF)
% IMP
HSG
AREA WEIGHTED* *
RUNOFF

COEFFICIENT

VOLUME (DCV)

TREATMENT
SYSTEM
1 1
6,099
1,290

21.1 D

0.43 144

BIOFILTRATION
*21
2 4,101
830

20.2 0

0.42 163
DMAs(2 .2+2.3)

TREEWELLS
*2.2
1,950 .
1,950
100
D
0 .90
*23
1341
1341
100
D

0.90 3
3 4 .924

2.812

57.1 D
064
173

BIOFILTRATION
4 -
3,889

0.00 0.0
D
0 .30
-

SELF -MITIGATING
5 4
11,505
9,661

84.0 D

0.80 506

BIOFILTRATION
6 5
7,187
2,561
35 .6
D

0.51 202

BIOFILTRATION
7 6
33 ,809
23,665
70 .0
D
0 .72
1,339

BIOFILTRATION/

AOUASAVE
8 -
1,427
0 0 .0
D
0 .30
-

SELF -MITIGATING
-*THE IMPERVIOUS AREA FROM DMA -2.1 IS REQUIRED TO BE TREATED BUT IT CAN NOT,THEREFORE IT WILL BE SWAPPED WITH THE ADDITIONAL AREA "DMA -2 .2" (HALF FRONTAGE STREET) THAT WILL TREAT THE OFFSITE IMPROVEMENT AREA VIA PROPOSED TREE - WELLS. - LOMA ALTA CREEK AND BUENA VISTA CREEK ARE EXISTING NATURAL

HYDROLOGIC FEATURES ( WATERCOURSES, SEEPS, SPRINGS, WETLANDS)

NO CRITICAL COARSE SEDIMENT YIELD AREAS TO BE PROTECTED

MULTI STORY STRUCTURES MINIMIZE IMPERVIOUS AREA
- **PER PERVIOUS C COEFFICIENT = 0.3 & IMPERVIOUS C COEFFICIENT = 0.9

SITE DESIGN AMPS
50-3

MINIMIZE IMPERVIOUS AREA
SD --4

MINI MIZE SOIL CDMPAC TION
SD -7

LANDSCAPING WITH NATIVE DROUGHT

TOLERANT SPECIES

SOURCE CONTROL NOTES
SC -1
5C-2
SC -6:

A
0 "NO DUMPING! FLOWS TO CREEK "

STORM DRAIN STENCILING AND

SING ACE
STENCIL ON -SITE INLETS: "NO
DUMPING! FLOWS TO CREE.,"
LANDSCAPE/OUTDOOR ) FFUIOI:L US;

PROVIDE IMP
ROOF AND EQUIPMENT: CONNECT

CONDENSATE DRAIN TO SANITARY

SEWER, PROVIDE ROOFING
AND/SECONDARY CONTAINMENT 1l

EQUIPMENT, AVOID USE OF

UNPROTECTED METALS
PLAZAS, SIC L `-
LOTS: S WL
0 DMA MAP 1 OF 2
FOR
WAX WING DRIVE 15 -LOTS

VISTA, CA
SWS
SWS E NGI NEERING, IN C.
ti_.I Vtl� s Ib1iLk ��On�e. 1u e100� • m .mu�

O BIOFILTRATION CHART (BF -1)
00 DSN.4
IMP k

ORIFICE

DIAMETER
(IN)

ORIFICE INVERT

ELEVATION
(�
OUTLET
PIPE
(IN)
# OF
RISERS

GRATE SIZE IN

FEET (N,Y)

BASIN TOTAL
SURFACE *

DEPTH (IN)

BASIN REQUIRED

TREATMENT AREA
(SF)
BASIN

BOTTOM AREA
(SF)

BASIN PROVIDED

TREATMENT AREA
(SF)

PERFORATED

PIPE DIAMETER
(IN)
MULCH
DEPTH
"A " (IN)

AMENDED

SOIL DEPTH
"B" (IN)

FILTER COURSE
DEPTH
"C1&C2" (IN)**

STORAGE
"0" (IN)***

BOTTOM BASIN

ELEVATION
(FT)

DISTANCE FROM

BOTTOM OF POND

TO TOP OF GRATE

TOP OF GRATE
ELEVATION+ +
(FT)
DCV
(OF)
VOLUME
PROVIDED**.
(CF)
AMP

ELEVATION
(FT)
100YR

ELEVATION
(FT)

EFFECTIVE

ELEVATION
( H)

TOP OF BERM

ELEVATION
(FT)

PRODDED

FREE BOARD
(IN)

SIDE SLOPE
Z:1
1 0.25
459.50'
6 1
1' X 1'
21"
79 121
121
6"
3"
18 "
6"
12"
462.50
0 .83'
463.33'
1 4
3 .,
463.33'
463.54'
463.66'
464 .25
7:08 "
2:1
3 0.25
457. 50'
8 1
1' X 1'
21 95
218
218
6 3
18 6
12 460 .50

0.83'
461.33'
173
580
461 .33
461.53
461.58
462.25

8.04 2:1
4 0. 26
455.50'
10 1
1' X 1'
21"
280
318
318
6"
3"
18 "
6"
12"
458 .50'

0.83'
459.33'
506
1,097
459.33'
459.60'
459.53'
460.25'

7.80 "
2:1
®
5 0.25
451.00'
10 1
1' X 1'
21"
110
141
141
6"
3"
18"
6"
12 "
455 .50'

0.83'
456.33'
202
396
456.33'
456.63'
456.69'
457.25'
6 .72"
2:1
erv
6 03
12 1
1' X 1'
21 "
731
1400
1400
-
3"
18"
3"
33"
455.00'

0.83'
455:83'
1,339
6,095
455.83'
456.04'
455,86'
456.75'

8.52"
2:1
456.25'
* FROM TOP OF MULCH TO TOP OF BERM
100-YR POND DEPTH

RAMP- DEPTH
100-YR STORAGE DEPTH

MULCH (A)
M EDIA (0)
WIIH A MIN 5" IN/HR

MLDIA SPECIFICATION
,NASH SAND (C-1)
2 N

BASIN BOTTOM
1—I
Ir
4, -RR STORAGE-AOUASAVE
(0).
** 3" ASTM 33 (TOP) , 3" ASTM NO 8 (BOTTOM)

BASIN TOP
II
II 1TIIrI�IIIII III
ORIFICE -1

RISER OUTLET STRUCTURE

F REE BOA RD

SURFACE TOTAL DEPTH

VEGETATON PER
LANDSCAPING PLAN .

HMP STORAGE
DEPTH

EXISTING GROUND
— -I III - - IMPERVIOUS LINER 30 M IL PVC OR EQUIV.
'.KITS CONTRACTOR TO SUBMIT PRODUCT DATA

TO ENGINEER OF RECORD FOR APP ROVAL
PRIOR TO CONSTRUCTION.

OUTLET PIPE

TREATMENT BOTTOM
AREA

FOR LETTERS (A RD D) PLEASE
SEE BIOFILTRATION CHART (BF -1)
BIOFILTRATION FACILITY DETA9_ (IMP -6)

RESTRICTOR PLATE
(SEE BELOW)

APPROVED CORROSION RESISTANT CONCRETE
ANCHORS (4%) WITH PLATE WASHERS
P •F PIP HI
SE

ONTINUO S BEAD OF SEALANT

ROUND RESTRICTO R PLATE PERIM ETER
LL

U TO CONCRETE WITH APPROVED

E (LOCTITE EPDXY -HEAVY DUTY) AND

CO NCRETE WEDGE ANCHOR BO LTS
AS -125 (1/2" DIA, 5" DEPTH)
I *f C -0R PLATE ELEVATION
"" =LOW -CONTROL ORIFICE
00 —I

ORIFICE (SEE BELOW )

RESTRIC TOR PLATE
ply,. p•• aN B• "IN

PER DETAIL AND CHA

ARUSAVE STORAGE PER

BIOFILTRATION DETAIL

AOUASAVE STORAGE

IMPERMEABLE L NER PER
R ISER .OTTOM BIOFILTRATON DETAIL
O7 BIOFILTRATION PLATE & ORIFICE DETAIL (IMP -6)
***(GRAVEL, ASTM 57) FOR IMPS (1,3,4,5), ++PER HMP
AQUASAVE FOR IMP -6
100-YR STORAGE DEPTH

MULCH (A)

MEDIA (H)
WITH A MIN 5" IN/HR

PER MEDIA SPECIFIC ATI ON
FILTER WA SH SAND (C-1)
FILTER PEA GRAVEL (02)
GRAVEL SAND (0
3/4 IN CRUSH ROCK
A" PERFORATED_,EIPF
(3' FROM THE BOTTOM)

BASIN TOP
100-YR POND DEP

T)L-III II
H- II -III -1I-

ORIFI CE
*** * INCLUDES: 12 " SURFACE 100% VOID
SOIL GRAVEL 40% VOID
90% VOID FOR AQUASAVE STORAGE (IMP -6)

RISER OUTLET STRUCTURE

TREATMENT BOTTOM
AREA
FOR LETTERS (A TO D).. PLEASE
SEE BIOFILTRATION CHART (BF -1)
BIOFILTRATION FACILITY DETAIL (IMPS 1.3.4,5)

RESTRICTOR PLATE
(SEE BELOW)

APPROV ED CORROSION RESISTANT CON CRETE
ANCHORS (4X) WITH PLATE WASHERS

PERF PIPE BEHIND

RISER WALL
TIN *. A* •F A NT

AROUND AROUND RESTRICTOR PLATE

ADHERED TO CONCRETE WITH APPROVED

ADHESIVE (LOCTITE EPDXY -HEAVY DUTY) AND

VESTIL CONCRET E WEDGE ANCHOR BOLTS
(M ODLE II 05-125 (1/2" DIA, 5" DEPTH)

SEE RESTRICTOR PLATE ELEVATION

ORIFICE (SEE BELOW )

BIOFILTRATION BASIN

PER DETAIL AND CHARFJ

GRAVEL PER

BIOFILTRATION DETAIL

GRAVEL STORAGE
FLOW -CONTROL ORIFICE 3" GRAVEL BASE

IMPERMEABLE LINER PER

BIOFILTRA TION DETAIL
BIOFILTRATION PLATE & CRIME DETAIL (IMPS 1,3,4,5)
NIS

FREE BOARD

SURFACE TOTAL DEPTH

VEGETATION PER

LANDSCAPING PLAN

HMP STORAGE
DEPTH

EXISTING GROUND
IMPERVIOUS CHER 30 MIL PVC OR EQUIV.

CONTRACTOR TO SUBMIT PRODUCT DATA

TO ENGINEER OF RECORD FOR APPROVAL
PRIOR TO CONSTRUCTION.

OUTLET PIPE
AQUASAVE (IMP -6)

SHE C OUNTY OF SAN DIEGO
LOWW

IMPACT TERN,O NN PLACE IINFILLTCRARON BAR OFAND
5 INCHES
PER HOUR. BSM SHALL RE COMPOSED OF THE FOLLOWING:

SANDY LOAM

LOMFOSSTON
RAND

COMPOST

SAND SILT CLAY
VOLUME
BD -50%
0-20%
20%
WEIGHT
T5-80% I10% MAXI= MAX
9% MAXI
' 9% COMPOST BY MICH RESULTS M APPROBMATELY
5% ORGANIC MATTER BY WONT .

NUTRIENT -SENSITIVE GSM MIX PER . FACTSHEET BF -2
TREE -WELL (I MP -2)
NTS
DMA MAP 2 OF 2
FOR
WAX WING DRIVE 15 -LOTS

VISTA, CA
SWS E NGI NEE RING, I NC.
vG�Eeri: :

ATTACHMENT 1B -TEMPLATE TABULAR DMA SUMMARY
The template tabular summary of DMAs must accompany the DMA Exhibit (Attachment 1A). A template table is provided below.

DMA ID
DMA Surface
Type (roof,
street, etc.)
DMA Area
(sq.ft.)
DMA Type
Structural
BMP ID
Proposed
Structural BMP
Type2
Structural BMP Size3
1 Building,
Patio,
Driveways,
Street,
Sidewalks
6,099
Drains to BMP
IMP -1
Biofiltration
Treatment area: 121 sf

2.1 (SWAP)
Building,
Patio,
Driveways,
Street,
Sidewalks
4,101
-
IMP -2
Tree -Well

5.5 W' x29' L
Tree -Well

2.2 (SWAP)
Frontage
Street
1,950
Drains to BMP

2.3 Sidewalk
1,341
Drains to BMP
3 Undisturbed
Pervious
Area
4,924
Drains to BMP
IMP -3
Biofiltration
Treatment area: 218 sf
4 Building,
Driveways,
Street,
Sidewalks
3,889
Self -mitigating
-
Self -Mitigating
-
5 Building,
Driveways,
Street,
Sidewalks
11,505
Drains to BMP
IMP -4
Biofiltration
Treatment area: 318 sf
6 Walkway,
driveway
7,187
Drains to BMP
IMP -5
Biofiltration
Treatment area: 141 sf
7 Building,
Patio,
Driveways,
Street,
Sidewalks
33,809
Drains to BMP
IMP -6
Biofiltration
Treatment area: 1400 sf
8 Pervious
Area
1,427
Self -mitigating
-
Self -Mitigating
-
1 DMA Type can only be: 1) Drains to BMP, 2) Self -mitigating, 3) De Minimis, or 4) Self -retaining 2 BMP Type must be consistent with terminology in the BMP Design Manual and/or CASQA Fact Sheets 3 Structural BMP Size is typically presented as an area (sq. ft.) or size (e.g., proprietary devices)

Page 32 of 38 ends

08/11/2026
PH2 533 of 876

ATTACHMENT 1C
08/11/2026
PH2 534 of 876

Appendix B: Storm Water Pollutant Control Hydrologic Calculations and Sizing Methods Worksheet B.3-1. Harvest and Use Feasibility Screening
Harvest and Use Feasibility Screening
Worsksheet B.3-1

1. present
Is
1 there a demand for harvested water (check all that apply) at the project site that is reliably during the wet season?
Toilet and urinal flushing Per Table B.3-3, the Irrigation demand 36 hour:

Moderate Plant Water Use = 1,470 gal / acre / 36 hrs
Landscape irrigation Proposed Planted Area (DMAs 1-8) = 35,062 sf or 0.81 acres Other: Harvest and Use is Infeasible 1,470 gal / acre x 0.81 acres / 7.48 gal / cf = 159 cf ►i4

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.

Per Table B.3-1, Residential flushes per day amounts to 9.3 gallon per resident per day.

This development will employ the use of low -flow toilets:

9.3 gallon Per resident per day x 60 residents x 1.5 days x (1 cf/7.48 Gal) = 112 cf per 36 hour demand

3. Calculate the DCV using worksheet B-2.1.

DCV (DMAs 1, 3, 5, 6,7) = 144 + 173 + 506 + 202 + 1,339 = 2,364 cubic feet

0.25"'2,210 cubic feet = 591 cubic feet > (159 +112) cubic feet 3a. Is the 36 -hour demand
greater than or equal to the
DCV?
3b. Is the 36 -hour demand greater
than 0.25DCV but less than the full
DCV?
3c. Is the 36 -hour
demand less than

0.25DCV?
Yes /
No
l=bp>
Yes
Yes /
No
l=>
4 V
Harvest and use appears to be
feasible. Conduct more detailed
evaluation and sizing
calculations to confirm that
DCV can be used at an adequate
rate to meet drawdown criteria.

Harvest and use may be feasible.

Conduct more detailed evaluation and
sizing calculations to determine
feasibility. Harvest and use may only
be able to be used for a portion of the
site, or (optionally) the storage may
need to be upsized to meet long term
capture targets while draining in
longer than 36 hours.

Harvest and use is
considered to be
infeasible.
08/11/2026
B-11
PH2
February 2016
535 of 876

ATTACHMENT 1D
08/11/2026
PH2 536 of 876

April 25, 2024 Project No. 23185-10
Mr. Michael Schweitzer, P.E.

SWS ENGINEERING, INC.
1635 Lake San Marcos Drive, Suite 200
San Marcos, CA 92078
Subject: Infiltration System Design Interpretive Report, Proposed Vista Project, South side of West Bobier Drive and East of Sports Park Way, Oceanside, San Diego County, California In accordance with your request, CW Soils is pleased to present this infiltration system interpretive report for the proposed Vista Project, located on the south side of West Bobier Drive and east of Sports Park Way, Oceanside, San Diego County, California. The purpose of our feasibility study was to determine the onsite infiltration rates and physical characteristics of the subsurface soils within the vicinity of the proposed infiltration systems. We have provided guidelines for the design of onsite infiltration systems. This interpretive report is intended to provide onsite infiltration rates for the existing soils.

PROPOSED DEVELOPMENT
Based on our understanding of the proposed project, will include three main buildings consisting of 14 units along with 3 ADU buildings consisting of 6 units, private streets, interior driveways, utilities, and on -site infiltration areas.

INFILTRATION TESTING

INFILTRATION TESTING
Aardvark Permeameter testing was utilized to conduct in -situ infiltration tests within the proposed basins on April 11, 2024, to evaluate the infiltration rate(s) in order to estimate the amount of storm water runoff that can infiltrate into the proposed systems. The testing utilizes the constant head method with extremely accurate (0.2 ml resolution) hydraulic conductivity testing under saturated conditions, for the determination of reliable in -situ infiltration rates. Automated readings are taken at 1 minute intervals until the rate becomes constant and saturated hydraulic conductivity for the particular soil has been reached. This is reflected by the flattening of the curve generated by sample test data as shown on the Water Consumption Rate graph (Plot of Water Consumption Rate 08/11/2026 " CW SOILS, 23251 Kent Court, p,QWrpeta, CA 92562.951-304-3935 . 537 of 876

vs. Time) in the Appendices herein. Steady Flow Rate is achieved when the Water Consumption Rate changes less than +/- 5% for 3 consecutive readings.

The Aardvark Permeameter was utilized in replacement of the Guelph Permeameter as recommended by Soil Moisture Equipment
Corporation, due to the higher reliability, accuracy, and ease of use.

The Aardvark Permeameter is the latest version of the Guelph Permeameter.

Infiltration testing was conducted in a 3 -inch diameter test hole, at depths of 3.5 to 4 feet deep. The approximate location of infiltration testing is indicated on the attached Infiltration Map, Plate 1.

Infiltration testing was located by property boundary measurement on the site plan and/or by using geographic features.

Relatively shallow Aardvark Permeameter testing (P-1 & P-2) was conducted using the guidelines of the product instruction manuals.

Stabilized infiltration test readings are summarized in the following table and more detailed test data recorded in the field can be found in Appendix A. The test results are anticipated to be representative of the soils found in the vicinity of the test locations.

INFILTRATION TEST SUMMARY
TEST
NUMBER

TEST HOLE

DIAMETER
(in)
HOLE
DEPTH
(in)

SOIL DESCRIPTION

INFILTRATION
RATE (in/hr)
P-1
3 48

0.19 Claey SAND
P-2
3 42

0.18 Claey SAND

FINDINGS
SOILS
A general description of the soils observed on site is provided below:

Cretaceous Tonalite (map symbol Kt): Cretaceous age plutonic rock consisting of tonalite was mapped throughout the site. The tonalite was observed to be light grayish brown, slightly moist to moist, and in a moderately hard to very hard state. Typically, the upper 1 to 3 feet of this unit is more weathered and not as hard.
08/11/2026 " CW SOILS, 23251 Kent Court, p,QWr eta, CA 92562.951-304-3935 ' 538 of 876

CONCLUSIONS AND RECOMMENDATIONS

GENERAL
The shallow in -situ soils have an average infiltration rate of 0.185 in/hr. in the aeras tested, with no additional factor of safety being applied.

PLAN REVIEW AND CONSTRUCTION SERVICES
This report has been prepared for the exclusive use of SWS and their authorized representative. It is unlikely to contain sufficient information for other parties or other uses. CW Soils should be provided the opportunity to review the final design plans and specifications prior to construction, in order to verify that the recommendations have been properly incorporated into the project plans and specifications. If CW Soils is not accorded the opportunity to review the project plans and specifications, we are not responsibility for misinterpretation of our recommendations.

We recommend that CW Soils be retained to provide soils engineering and engineering geologic services during the grading and foundation excavation phases of work, in order to allow for design changes in the event that the subsurface conditions differ from those anticipated prior to construction.

CW Soils should review any changes in the project and modify the conclusions and recommendations of this report in writing. This report along with the drawings contained within are intended for design input purposes only and are not intended to act as construction drawings or specifications. In the event that conditions during grading or construction operations appear to differ from those indicated in this report, our office should be notified immediately, as appropriate revisions may be required.

REPORT LIMITATIONS
Our services were performed using the degree of care and skill ordinarily exercised, under similar circumstances, by reputable soils engineers and geologists, practicing at the time and location this report was prepared. No warranty, expressed or implied, is made as to the conclusions and professional advice included in this report.

Soils vary in type, strength, and other engineering properties between points of observation and exploration.

Groundwater and moisture conditions can also vary due to natural processes or the works of man on this or adjacent properties. As a result, we do not and cannot have complete knowledge of the subsurface conditions beneath the proposed project. No practical study can completely eliminate uncertainty with regard to the anticipated geologic and soils engineering conditions in connection with a proposed project. The conclusions and recommendations within this report are based upon the findings at the points of observation and are subject to confirmation by CW Soils based on the conditions revealed during grading and construction operations. 08/11/2026 " CW SOILS, 23251 Kent Court, p,QWrpeta, CA 92562.951-304-3935 . 539 of 876

This report was prepared with the understanding that it is the responsibility of the owner, to ensure that the conclusions and recommendations contained herein are brought to the attention of the other project consultants and are incorporated into the plans and specifications. The owners' contractor should implement the recommendations in this report and notify the owner as well as our office if they consider any of the recommendations presented herein to be unsafe or unsuitable.

CW Soils appreciates the opportunity to otter our services on this project. If' we can be of further assistance, please do not hesitate to contact the undersigned at your convenience.

Respectfully submitted,
CW Soils
Chad E. Welke, PG, CEG, PE
Principal Geologist/Engineer
Distribution: (1) Addressee (email)
Attachments: Appendix A — Infiltration Test Results
Plate 1 — Infiltration Map (Rear of text)
08/11/2026
sO LS, 23251
PH2 540 of 876

APPENDIX A

INFILTRATION TEST RESULTS
CW SOILS, 23251 Kent Court, Murrieta, CA 92562 - 951-304-3935 08/11/2026
PH2 541 of 876

Aarclvarl< rermeamete s
Location: 23185
Site: P1
Time interval between readings: 1 minute
Steady Flow Rate achieved when Water
Consumption Rate changes less than
+/- 10 % for 3 consecutive readings
Notes:

Ksat Method:

Glover Solution
Steady Flow Rate:

Temp. Adj. FR:

Percolation Rate:

Ksat:

39.800 ml/min

39.880 ml/min

1.260 min/cm

0.19 Inches / hour
-41=

3.1 inches
70°F
48 inches

16.1 inches
Soil Texture -Structure Category:

Hole Diameter
Water Temperature
Hole Depth
Water Height in Hole
Water Table Depth
Longitude:

Latitude:

Degrees Minutes Seconds
0 0
0 0
0 0
East
North
08/11/2026
PH2
542 of 876

Water Consumption Rate
500
•
400
300
E
a
E
200
0 E
100
0 3:50 PM
2000
1500
1000
500
0 3:55 PM
4:00 PM
4:05 PM
4:10 PM
Total Water Consumed
4:15 PM
3:5C PM 3:55 PM
4:00 PM
4 05 PM
4:10 PM
4:15 PM
08/11/2026
PH2 543 of 876

Time
Reservoir Water
Level
Elapsed Time Interval Water Total Water
Interval Consumed Consumed
Water
Consumption
Rate
3:46:31 PM 7352.8 ml
3:47:31 PM 6884.8 ml 1 minute 468.0 ml 468.0 ml 468.000 ml/min 3:48:31 PM 6787.8 ml 1 minute 97.0 ml 565.0 ml 97.000 ml/min 3:49:32 PM 6719.4 ml 1 minute 68A ml 633.4 ml 67.279 ml/min 3:50:31 PM 6663.4 ml 59 seconds 56.0 ml 689.4 ml 56.949 ml/min 3:51:32 PM 6612.0 ml 1 minute 51.4 ml 740.8 ml 50.557 ml/min 3:52:32 PM 6564.6 ml 1 minute 47.4 ml 788.2 ml 47.400 ml/min 3:53:32 PM 6522.0 ml 1 minute 42.6 ml 830.8 ml 42.600 ml/min 3:54:32 PM 6479.4 ml 1 minute 42.6 ml 873.4 ml 42.600 ml/min 3:55:32 PM 6440.6 ml 1 minute 38.8 ml 912.2 ml 38.800 ml/min 3:56:32 PM 6402.6 ml 1 minute 38.0 ml 950.2 ml 38.000 ml/min 3:57:32 PM 6365.0 ml 1 minute 37.6 ml 987.8 ml 37.600 ml/min 3:58:32 PM 6326.0 ml 1 minute 39.0 ml 1026.8 ml 39.000 ml/min 3:59:33 PM 6287.8 ml 1 minute 38.2 ml 1065.0 ml 37.574 ml/min 4:00:33 PM 6249.4 ml 1 minute 38.4 ml 1103.4 ml 38.400 ml/min 4:01:33 PM 6212.6 ml 1 minute 36.8 ml 1140.2 ml 36.800 ml/min 4:02:33 PM 6178.2 ml 1 minute 34.4 ml 1174.6 ml 34.400 ml/min 4:03:33 PM 6142.2 ml 1 minute 36.0 ml 1210.6 ml 36.000 ml/min 4:04:33 PM 6106.6 ml 1 minute 35.6 ml 1246.2 ml 35.600 ml/min 4:05:33 PM 6073.4 ml 1 minute 33.2 ml 1279.4 ml 33.200 ml/min 4:06:34 PM 6042.2 ml 1 minute 31.2 ml 1310.6 ml 30.689 ml/min 4:07:33 PM 6009.6 ml 59 seconds 32.6 ml 1343.2 ml 33.153 ml/min 4:08:34 PM 5976.6 ml 1 minute 33.0 ml 1376.2 ml 32.459 ml/min 4:09:34 PM 5945.6 ml 1 minute 31.0 ml 1407.2 ml 31.000 ml/min 4:10:34 PM 5914.8 ml 1 minute 30.8 ml 1438.0 ml 30.800 ml/min 4:11:34 PM 5885.0 ml 1 minute 29.8 ml 1467.8 ml 29.800 ml/min 4:12:34 PM 5854.6 ml 1 minute 30.4 ml 1498.2 ml 30.400 ml/min 4:13:34 PM 5826.8 ml 1 minute 27.8 ml 1526.0 ml 27.800 ml/min 4:14:34 PM 5795.8 ml 1 minute 31.0 ml 1557.0 ml 31.000 ml/min 4:15:35 PM 5766.0 ml 1 minute 29.8 ml 1586.8 ml 29.311 ml/min 4:16:35 PM 5737.0 ml 1 minute 29.0 ml 1615.8 ml 29.000 ml/min 4:17:35 PM 5708.4 ml 1 minute 28.6 ml 1644.4 ml 28.600 ml/min 4:18:35 PM 5680.6 ml 1 minute 27.8 ml 1672.2 ml 27.800 ml/min Ignore
Reading
08/11/2026
PH2 544 of 876

Aarclvarl< rermeamete s
Location: 23185
Site: P2
Time interval between readings: 1 minute
Steady Flow Rate achieved when Water
Consumption Rate changes less than
+/- 10 % for 3 consecutive readings
Notes:

Ksat Method:

Glover Solution
Steady Flow Rate:

Temp. Adj. FR:

Percolation Rate:

Ksat:

38.000 ml/min

38.076 ml/min
L320 min/cm

0.18 Inches / hour
-41=

3.1 inches
70°F

42.1 inches

16.1 inches
Soil Texture -Structure Category:

Hole Diameter
Water Temperature
Hole Depth
Water Height in Hole
Water Table Depth
Longitude:

Latitude:

Degrees Minutes Seconds
0 0
0 0
0 0
East
North
08/11/2026
PH2
545of876

Water Consumption Rate
1200
1000
SOD
600
a
E
0 E
400
200
2500
200C
150C
1000
500
4:35 PM
4:40 PM
4:45 PM
4:5C PM
4:55 PM
5:D0 PM
4:35 PM
4:40 PM
4:45 PM
4:50 PM
4:55 PM
5:D0 PM
Total Water Consumed
08/11/2026
PH2
546 of 876

Time
Reservoir Water
Level

4.31:45 PM 8338.0 ml
4:32:45 PM 7189.8 ml
4:33:45 PM 7016.4 ml
4:34:45 PM 6940.8 ml
4:35:45 PM 6885.6 ml
4:36:45 PM 6840.4 ml
4:37:46 PM 6801.0 ml
4:38:46 PM 6760.8 ml
4:39:46 PM 6724.6 ml
4:40:46 PM 6687.0 ml
4:41:46 PM 6647.6 ml
4:42:46 PM 6611.6 ml
4:43:46 PM 6572.8 ml
4:44:46 PM 6533.2 ml
4:45:47 PM 6497.6 ml
4:46:47 PM 6459.4 ml
4:47:47 PM 6424.0 ml
4:48:47 PM 6390.8 ml
4:49:47 PM 6357.0 ml
4:50:47 PM 6323.0 ml
4:51:48 PM 6287.2 ml
4:52:48 PM 6252.8 ml
4:53:48 PM 6220.4 ml
4:54:48 PM 6188.2 ml
4:55:48 PM 6155.8 ml
4:56:48 PM 6121.0 ml
4:57:48 PM 6089.6 ml
4:58:48 PM 6057.4 ml
4:59:48 PM 6024.8 ml
5:00:48 PM 5994.0 ml
5:01:48 PM 5962.0 ml
Elapsed Time Interval Water Total Water
Interval Consumed Consumed
minute
minute
minute
minute
minute
minute
minute
minute
minute
minute
minute
minute
minute
minute
minute
minute
minute
minute
minute
minute
minute
minute
minute
minute
minute
minute
minute
minute
minute
minute
1148.2 ml
173.4 ml

75.6 ml

55.2 ml

45.2 ml

39.4 ml

40.2 ml

36.2 ml

37.6 ml

39.4 ml

36.0 ml

38.8 ml

39.6 ml

35.6 ml

38.2 ml

35.4 ml

33.2 ml

33.8 ml

34.0 ml

35.8 ml

34.4 ml

32.4 ml

32.2 ml

32.4 ml

34.8 ml

31.4 ml

32.2 ml

32.6 ml

30.8 ml

32.0 ml
1148.2 ml
1321.6 ml
1397.2 ml
1452.4 ml
1497.6 ml
1537.0 ml
1577.2 ml
1613.4 ml
1651.0 ml
1690.4 ml
1726.4 ml
1765.2 ml
1804.8 ml
1840.4 ml
1878.6 ml
1914.0 ml
1947.2 ml
1981.0 ml
2015.0 ml
2050.8 ml
2085.2 ml
2117.6 ml
2149.8 ml
2182.2 ml
2217.0 ml
2248.4 ml
2280.6 ml
2313.2 ml
2344.0 ml
2376.0 ml
Water
Consumption
Rate
1148.200 ml/min
173.400 ml/min

75.600 ml/min

55.200 ml/min

45.200 ml/min

38.754 ml/min

40.200 ml/min

36.200 ml/min

37.600 ml/min

39.400 ml/min

36.000 ml/min

38.800 ml/min

39.600 ml/min

35.016 ml/min

38.200 ml/min

35.400 ml/min

33.200 ml/min

33.800 ml/min

34.000 ml/min

35.213 ml/min

34.400 ml/min

32.400 ml/min

32.200 ml/min

32.400 ml/min

34.800 ml/min

31.400 ml/min

32.200 ml/min

32.600 ml/min

30.800 ml/min

32.000 ml/min
Ignore
Reading
08/11/2026
PH2 547 of 876

a)
N
cW
Co
al

15.5•
S89'17'04"E 87.68'

ACC VALLEY
GUTTER
rn
l
M

41.8'

15.5'
N.

Kt
\:
0 11
L_I]
0 L=95.24, 50.00
D=5'43'55" T D=5'441-373"
L=105.04 , =1050.00
Z1H
0 1)
0 .a
N
2 493'
-!V12'
0 N

HOA ACCESS AND

LANDSCAPE EASEMENT
N
r 24'
0 P
TP-3.0 _
i
1433 j'
TP-4
• 143.8
CJ
143.8
.:J,c;TI J LO :>`,
1\1O's 25.';:
4' -
L11
0 N
TP-5
1418'

Y OF VISTA
• 61QhLIRATTON BASMI
LOT 22
h
N
16 R
0,
N
l 1.
20'

ACC VALLEY
GUTTER

62.7'
❑ , \
4 35.7
N86' 7.04"W 2$7.67'
II

ON BASIN
P— IJrx-1
l
a
N

KNOLL CF -L ST
TRACT .\JO. :45-J
WAX WING DR Geologic Units
LEGEND
Locations are Approximate
u
ADD
ADU
ADU
ADU
HOA ACCESS AND _ _

LAND EASEMENT
Kt — Cretaceous Tonalite
Symbols
>Q
TP-7
HA -1
— Exploratory Test Pit
N
LA
— Exploratory Hand Auger
5'
J
CW
Proposed Vista

GEOTECHNICAL MAP
23185-10
1" = 40`
SOILS
2024
PLATE 1
Uti/'I "I /LU1b 1-'111
b4d OT t5/b

Appendix I: Forms and Checklists
Categorization of Infiltration Feasibility
Condition
Form 18
Part 1 - Full Infiltration Feasibility Screening Criteria perspective without any undesirable
Would infiltration of the full design volume be feasible from a physical consequences that cannot be reasonably mitigated?
Criteria
Screening Question
Yes
No
1 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:

The average Infiltration rate is 0.185 in/hr (with No Safety Factor being applied) per infiltration testing report by CW Soils, dated April 25, 2024 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:

Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide narrative discussion of study/data source applicability.

I-3
08/11/2026 PH2
February 2016
549 of 876

Appendix I: Forms and Checklists
Form I-8 Page 2 of 4
Criteri
a
Screening Question
Yes
No
3 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.

Provide basis:

Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide narrative
discussion of study/data source applicability.
4 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.

Provide basis:

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 y
would not generally be feasible or desirable to achieve a "full infiltration" design.

Proceed to Part 2
No
Full Infiltration
*To be completed using gathered site information and best professional judgment considering the de =coition of MEP in the MS4 Permit. Additional testing and/or studies may be required by the City to substantiate findings. 08/11/2026
I-4
PH2
February 2016
550 of 876

Appendix I: Forms and Checklists
Form 1-8 Page 3 of 4
Part 2 — Partial Infiltration vs. No Infiltration Feasibility Screening Criteria feasible without any negative
Would infiltration of water in any appreciable amount be physically consequences that cannot be reasonably mitigated?
Criteria
Screening Question
Yes
No
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.

X
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.
x
Provide basis:

Site having low infiltration rate of 0.185 in/hr (with no Safety Factor being applied) and other site constrains like building footing, utilities
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. 08/11/2026
I-5
PH2
February 2016
551 of 876

Appendix I: Forms and Checklists
Form I-8 Page 4 of 4
Criteria
Screening Question
Yes
No
-
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.

Provide basis:

Summarize
findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide narrative of study/data source applicability and why it was not feasible to mitigate low infiltration rates. discussion
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.

Provide basis:

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 5-8 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 Partial
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. 08/11/2026
I-6
PH2
February 2016
552 of 876

ATTACHMENT IE
08/11/2026
PH2 553 of 876

9Z0Z/ I. 1. /80
912 4° 1799
Appendix B: Storm Water Pollutant Control Hydrologic Cal culations and Sizing M eth ods Figu re B.1-1: 85th Percentile 24 -hour Isopluvial Map
Lege nd
eith P ERCE NTILE IE✓P4N PL
Erj INCONPOR.ED Olt v
NOTE
The & 5N peemn blle.s a 20 r:wr ramlall lotel.
it repre.tne a value such that a5% of the
o bserved 24 ho ur rem. tota ls tom be lest
b ane. v alu e
www. sandiegocounty.gov/stormwa ter
B-6
Eff ective Janu ary 1, 2019

Automated Worksheet B.1: Calculation of Design Capture Volume (V2.0 Category
#
Description i ii
er
Units
1 Drainage Basin ID or Name
DMA -1
DMA -3
DMA -5
DMA -6
DMA -7
unitless
2 85th Percentile 24 -hr Storm Depth

0.66 0.66

0.66 inches
3 Impervious Surfaces Not Directed to Dispersion Area (C=0.90) 1,290
2,812
9,661
2,56 I
23,665
sq-ft
Standard
Drainage Basin
4 Semi -Pervious Surfaces Not Serving as Dispersion Area (C=0.30) sq-ft
5 Engineered Pervious Surfaces Not Serving as Dispersion Area (C=0.10) sq-ft
Inputs
6 Natural Type A Soil Not Serving as Dispersion Area (C=0.10) sq-ft
7 Natural Type B Soil Not Serving as Dispersion Area (C=0.14) sq-ft
8 Natural Type C Soil Not Serving as Dispersion Area (C=0.23) sq-ft
9 Natural Type D Soil Not Serving as Dispersion Area (C=0.30) 4,809
2,1 12
I ,844
4,626
1(1,144
sq—fl:
10 Does Tributary Incorporate Dispersion, Tree Wells, and/or Rain Barrels? No
No
No
No
No
yes/no
11 Impervious Surfaces Directed to Dispersion Area per SD -B (Ci=0.90) sq-ft
12 Semi -Pervious Surfaces Serving as Dispersion Area per SD -B (Ci=0.30) sq-ft
Dispersion
13 Engineered Pervious Surfaces Serving as Dispersion Area per SD -B (Ci=0.10) sq-ft
14 Natural Type A Soil Serving as Dispersion Area per SD -B (Ci=0.10) sq-ft
Area, Tree Well
& Rain Barrel
Inputs
15 Natural Tip e B Soil Servin • as Dis . ersion Area . er SD -B Ci=0.14 - -
s. -ft
-
16 Natural Type C Soil Serving as Dispersion Area per SD -B (Ci=0.23) sq-ft
(Optional)
17 Natural Type D Soil Serving as Dispersion Area per SD -B (Ci=0.30) sq-ft
18 Number of Tree Wells Proposed per SD _A
19 Average Mature Tree Canopy Diameter
ft
20 Number of Rain Barrels Proposed per SD -E
21 Average Rain Barrel Size
gal
22 Total Tributary Area
6,099
4,924
11,505
7,187
33,809
sq-ft
Initial Runoff
23 Initial Runoff Factor for Standard Drainage Areas

0.43 0.64

0.80 0.51

0.72 unties
Factor
Calculation
24 Initial Runoff Factor for Dispersed & Dispersion Areas

0.00 0.00

0.00 unitless
25 Initial Weighted Runoff Factor

0.43 0.64

0.80 0.51

0.72 unitless
26 Initial Design Capture Volume
144
173
506
202
1,339
cubic -feet
27 Total Impervious .Area Dispersed to Pervious Surface 0 0
0 0
0 sq-ft
Dispersion
Area
Adjustments
28 Total Pervious Dis. ersion Area
0 0
0 0
0 s. -ft
29 Ratio of Dispersed Im.ervious Area to Pervious Dis .ersion Area a/a
n/a
a/a
n/a
n/a
ratio
30 Adjustment Factor for D' persed&Dis.ersion Areas

1.00 1.00

1.00 ratio
31 Runoff Factor After Dispersion Techniques

0.43 0.64

0.80 0.51

0.72 unitless
32 Design Capture Volume After Dispersion Techniques
144
173
506
202
1,339
cubic -feet
Tree & Barrel
33 Total Tree Well Volume Reduction
0 0
0 0
0 cubic -feet
Adjustments
34 Total Rain Barrel Volume Reduction
0 0
0 0
0 cubic -feet
35 Final Adjusted Runoff Factor

0.43 0.64

0.80 0.51

0.72 unitless
Results
36 Final Effective Tnbu . Area
2,623
3,151
9,204
3,665
24,342
s. -ft
37 Initial Design Capture Volume Retained by Site Design Elements 0 0
0 0
0 cubic -feet
38 Final Design Capture Volume Tributary to BMP
144
173
506
202
1,339
cubic -feet
No Warning Messages,
08/11/2026
PH2 555 of 876

9Z0Z/ L I./80
91940 999
Automated Worksheet B.2: Retenti on Requirements (V2.0) Megory
#
Descripti on
u
in
u
n
Units
1 Drainage Basin ID or Name
DMA -1
DM A -3
DM A -5
DM A -6
DMA -7
u nitless
2 85th Percentil e Rainfall D epth
0 .66

0.66 0.66

0.66 0.66
inch es
a sic Ana l, s;;:
3 Predominant NRCS S oil Type Within BMP Location
D
D
D
D
D
unitless
4 Is proposed BMP location R estri cted or Unr estrict ed. for Infiltr atio n Activities? Restricted
Restricted
R estri cted
Restricted
Restricted
unitless
5 Nature of Rest riction
Soil Type
Soil Typ e
Soil Type
Soil Type
S oil Typ e
unitless
6 Do Minimum Retenti on Req uirements Apply to this Project? Yes
Yes
Yes
Yes
Yes
yes/no
7 Are Habit able Structures Greater than 9 Stories Proposed? No
No
No
No
No
yes/n o
Advance _
A nalys'_',
8 Has Geotechnical Engineer Performed an Infiltrati on Analysis? Yes
Yes
Yes
Yes
Yes
yes/no
9 Design Infiltrati on Rate Recommended by Geotechnical Engineer 0 .093

0.093
0 .093
0 .093

0.093
in/hr
Result
10 Design Infiltration Rate Used To Determine Retention Requirements 0 .000

0.000

0.000
0 .000
in/hr
11 Percent of A verage Annual Run off that M ust be Retained withi n DM A

1.5%
1 .5 %

1.5%

1.5%
1 .5%
percentage
12 Fraction of DCV Requiring R etention
0 .01

0.01 0.01
0 .01
0 .01
ratio
13 Required Retention Volume
1 2
5 2
13 cubic -feet
No Warn ing Messages

Automated Worksheet B.3: BMP Performance (V2.0)
No offset.

AcuaSave Stora e is proposed
Category
#
Description
Units
1 Drainage Basin ID or Name
DMA -1
DMA -3
DMA -5
DMA -6
DMA -7
sq-ft
2 Design Infiltration Rate Recommended

0.000

0.000
in/hr
3 Design Capture Volume Tributary to BMP
144
173
506
202
1,339
cubic -feet
4 Is BMP Vegetated or Unvegetated?
Vegetated
Vegetated
Vegetated
Vegetated
Vegetated
unitless
5 Is BMP Impermeably Lined or Unlined?
Lined
Lined
Lined
Lined
Lined
unitless
6 Does BMP Have an Underdrain?
Underdrain
Underdrain
Underdrain
Underdrain
Underdrain
tintless
7 Does BMP Utilize Standard or Specialized Media?
Standard
Standard
Standard
Standard
Standard
unitless
8 Provided Surface Area
121
218
318
141
1,400
sq-ft
P Inputs
9 Provided Surface Ponding Depth
10 10
10 10
10 inches
10 Provided Soil Media Thickness
24 24
24 24
24 inches
11 Provided Gravel Thickness (Total Thickness)
15 15
15 15
33 inches
12 Underdrain Offset
3 3
3 3
0 V
inches
13 Diameter of Underdrain or Hydromod Orifice (Select Smallest)

0.25 0.25

0.26 0.25

0.80 inches
14 Specialized Sod Media Filtration Rate
in/hr
15 Specialized Sod Media Pore Space for Retention
unitless
16 Specialized Soil Media Pore Space for Biofiltration
unidess
17 Specialized Gravel Media Pore Space
unitless
18 Volume Infiltrated Over 6 Hour Storm
0 0
0 0
0 cubic -feet
19 Ponding Pore Space Available for Retention

0.00 0.00

0.00 unitless
20 Soil Media Pore Space Available for Retention

0.05 0.05

0.05 unitless
21 Gravel Pete Space Available for Retention (Above Underdrain)

0.00 0.00

0.00 unidess
Retention 22
Calculations
23 Gravel Pore S• ace Available for Retention r - ow Underderia

0.40 0.40

0.40 unitless
Effective Retention Depth

2.40 2.40

1.20 inches
24 Fraction of DCV Retained (Independent of Drawdown Time)

0.17 0.25

0.13 0.14

0.10 ratio
25 Calculated Retention Storage Drawdown Time
120
120
120
120
120
hours
26 Efficacy of Retention Processes

0.19 0.26

0.15 0.16

0.12 ratio
27 Volume Retained by BMP (Considering Drawdown Time)
28 46
76 33
162
cubic -feet
28 Design Capture Volume Remaining for Biofiltration
116
127
430
169
1,177
cubic -feet
29 Max Hydromod Flow Rate through Underdrain

0.0032

0.0035

0.0032

0.0396
cfs
30 Max Soil Filtration Rate Allowed by Underdrain Orifice

1.15 0.64

0.47 0.98

1.22 in/hr
31 Soil Media Filtration Rate per Specifications

5.00 5.00

5.00 in/hr
32 Soil _Media Filtration Rate to be used for Sizing

1.15 0.64

0.47 0,98

1.22 in/hr
33 Depth Biofiltered Over 6 Hour Stoem

6.87 3.82

2.83 5.90

7.33 inches
Biofiltration
Calculations
34 Ponding Pore Space Available for Biofiltration

1.00 1.00

1.00 unitless
35 Soil Media Pore Space Available for Biofiltration

0.20 0.20

0.20 unidess
36 Gravel Pore Space Available for Biofiltration (Above Underdrain)

0.40 0.40

0.40 unidess
37 Effective Depth of Biofiltration Storage

19.60 19.60

28.00 inches
38 Drawdown Time for Surface Ponding
9 16
21 10
8 hours
39 Drawdown Time for Effective Biofiltration Depth
17 31
42 20
23 hours
40 Total Depth Biofdtered

26.47 23.42

22.43 25.50

35.33 inches
41 Option 1 - Biofilter 1.50 DCV: Target Volume
175
191
644
254
1,766
cubic -feet
42 Option 1 - Provided Biofiltration Volume
175
191
594
254
1,766
cubic -feet
43 Option 2 - Store 0.75 ILCV: Target Volume
87 96
322
127
883
cubic -feet
44 Option 2- Provided Storage Volume
87 96
322
127
883
cubic -feet
45 Portion of Biofiltration Performance Standard Satisfied

1.00 1.00

1.00 ratio
Result
46 Do Site Design Dements and BMPs Satisfy Annual Retention Requirements? Yes
Yes
Yes
Yes
Yes
yes/no
47 Overall Portion of Performance Standard Satisfied (BMP Efficacy Factor)

1.00 1.00

1.00 ratio
48 Deficit of Effectively Treated Stormwater
0 0
0 0
0 cubic -feet
Attentiogl
at least 3 inches of gravel below the uaderdraia. lflined, a maximum of 3 inches of gravel is permitted beneath uaderdeaia - BMPs must have
08/11/2026
PH2 557 of 876

Appendix E: BMP Design Fact Sheets
E.12 BF -1 Biofiltra.;,^"
Location: 43rd Street and Logan Avenue, San Diego, California Description
MS4 Permit Category
Biofiltration
Manual Category
Biofiltration
Applicable Performance
Standard
Pollutant Control
Flow Control
Primary Benefits
Treatment
Volume Reduction (Incidental)
Peak Flow Attenuation (Optional)
Biofiltration (Bioretention with underdrain) facilities are vegetated surface water systems that filter water through vegetation, and soil or engineered media prior to discharge via underdrain or overflow to the downstream conveyance system. Bioretention with underdrain facilities are commonly incorporated into the site within parking lot landscaping, along roadsides, and in open spaces. Because these types of facilities have limited or no infiltration, they are typically designed to provide enough hydraulic head to move flows through the underdrain connection to the storm drain system.

Treatment is achieved through filtration, sedimentation, sorption, biochemical processes and plant uptake.

Typical bioretention with underdrain components include:
• Inflow distribution mechanisms (e.g., perimeter flow spreader or filter strips) • Energy dissipation mechanism for concentrated inflows (e.g., splash blocks or riprap) • Shallow surface ponding for captured flows
• Side slope and basin bottom vegetation selected based on expected climate and ponding depth • Non -floating mulch layer (Optional)
• Media layer (planting mix or engineered media) capable of supporting vegetation growth • Filter course layer consisting of aggregate to prevent the migration of fmes into uncompacted native soils or the aggregate storage layer
• Aggregate storage layer with underdrain(s)
• Impermeable liner or uncompacted native soils at the bottom of the facility • Overflow structure
08/11/2026
E-66
PH2
February 2016
558 of 876

Appendix E: BMP Design Fact Sheets
CURB
CURB CUT.
12" MIN.

CURB CUT

VEGETATED SIDE SLOPE

MEDIA SURFACE AREA

APRON FOR ENERGY
* DISSIPATION

W W W W

W Y W W

W W W W
W3H:1V (MIN.)

EXCAVATED SLOPE
(SHOWN AT 1 H:1 V)
MIN. 18" MEDIA WITH
MIN. 5 IN/HR

FILTRATION RATE

SATURATED STORAGE
(OPTIONAL)

FILTER COURSE

AGGREGATE STORAGE LAYER

CLEANOUT
2% MAX. FINISH GRADE

OVERFLOW

STRUCTURE
PLAN

NOT TO SCALE
4-6" DROP FROM CURB CUT TO APRON

APRON FOR ENERGY DISSIPATION
6" MIN. TO 12" MAX.

SURFACE PONDING

CLEANOUT

MAINTENANCE
ACCESS
(AS NEEDED)
W3H:1V (MIN.)

W W W W

UNDERDRAIN W W W
W W W
2" MIN. FREEBOARD
3" WELL -AGED, SHREDDED

HARDWOOD MULCH
(OPTIONAL) MAINTENANCE
ACCESS
(AS NEEDED)

OVERFLOW

STRUCTURE

IMPERMEABLE LINER (OPTIONAL)
MIN. 3" AGGREGATE BELOW UNDERDRAIN
MIN. 6" DIAMETER UNDERDRAIN

EXISTING UNCOMPACTED SOILS

SECTION A -A'

NOT TO SCALE
Typical plan and Section view of a Biofiltration BMP
08/11/2026
E-67
PH2
February 2016
559 of 876

Appendix E: BMP Design Fact Sheets
Design Adaptations for Project Goals
Biofiltration Treatment BMP for storm water pollutant control. The system is lined or un-lined to provide incidental infiltration, and an underdrain is provided at the bottom to carry away filtered runoff. This configuration is considered to provide biofiltration treatment via flow through the media layer. Storage provided above the underdrain within surface ponding, media, and aggregate storage is considered included in the biofiltration treatment volume. Saturated storage within the aggregate storage layer can be added to this design by raising the underdrain above the bottom of the aggregate storage layer or via an internal weir structure designed to maintain a specific water level elevation.

Integrated storm water flow control and pollutant control configuration. The system can be designed to provide flow rate and duration control by primarily providing increased surface ponding and/or having a deeper aggregate storage layer above the underdrain. This will allow for significant detention storage, which can be controlled via inclusion of an outlet structure at the downstream end of the underdrain.

Design Criteria and Considerations
Bioretention with underdrain must meet the following design criteria. Deviations from the below criteria may be approved at the discretion of the City Engineer if it is determined to be appropriate:

Siting and Design
Intent/Rationale
Placement observes geotechnical
recommendations regarding potential hazards
(e.g., slope stability, landslides, and liquefaction
zones) and setbacks (e.g., slopes, foundations,
utilities).

Must not negatively impact existing site
geotechnical concerns.

An impermeable liner or other hydraulic
restriction layer is included if site constraints
indicate that infiltration or lateral flows should
not be allowed.

Lining prevents storm water from
impacting groundwater and/or sensitive
environmental or geotechnical features.

Incidental infiltration, when allowable,
can aid in pollutant removal and
groundwater recharge.

Contributing tributary area shall be ≤ 5 acres
(≤ 1 acre preferred).

Bigger BMPs require additional design
features for proper performance.

Contributing tributary area greater than 5
acres may be allowed at the discretion of
the City Engineer if the following
conditions are met: 1) incorporate design
features (e.g. flow spreaders) to
minimizing short circuiting of flows in
08/11/2026
E-68
PH2
February 2016
560 of 876

Appendix E: BMP Design Fact Sheets
Siting and Design Intent/Rationale
the BMP and 2) incorporate additional
design features requested by the City
Engineer for proper performance of the
regional BMP.
d Finish grade of the facility is ≤ 2%.

Flatter surfaces reduce erosion and
channelization within the facility.

Surface Ponding
Surface ponding is limited to a 24 -hour
drawdown time.

Surface ponding limited to 24 hour for
plant health. Surface ponding drawdown
time greater than 24 -hours but less than
96 hours may be allowed at the
discretion of the City Engineer if
certified by a landscape architect or
agronomist.

Surface ponding depth is ≥ 6 and ≤ 12 inches.

Surface ponding capacity lowers
subsurface storage requirements. Deep
surface ponding raises safety concerns.

Surface ponding depth greater than 12
inches (for additional pollutant control
or surface outlet structures or flow -
control orifices) may be allowed at the
discretion of the City Engineer if the
following conditions are met: 1) surface
ponding depth drawdown time is less
than 24 hours; and 2) safety issues and
fencing requirements are considered
(typically ponding greater than 18" will
require a fence and/or flatter side slopes)
and 3) potential for elevated clogging risk
is considered.

A minimum of 2 inches of freeboard is
provided.

Freeboard provides room for head over
overflow structures and minimizes risk
of uncontrolled surface discharge.
d Side slopes are stabilized with vegetation and
u are = 3H:1V or shallower.

Gentler side slopes are safer, less prone
to erosion, able to establish vegetation
more quickly and easier to maintain.

Vegetation
08/11/2026
E-69
PH2
February 2016
561 of 876

Appendix E: BMP Design Fact Sheets
Siting and Design
Intent/Rationale
Plantings are suitable for the climate and Plants suited to the climate and ponding expected ponding depth. A plant list to aid in depth are more likely to survive. selection can be found in Appendix E.20.

An irrigation system with a connection to
water supply should be provided as needed.

Seasonal irrigation might be needed to
keep plants healthy.

Mulch
A minimum of 3 inches of well -aged, shredded
hardwood mulch that has been stockpiled or
stored for at least 12 months is provided.

Mulch will suppress weeds and maintain
moisture for plant growth. Aging mulch
kills pathogens and weed seeds and
allows the beneficial microbes to
multiply.

Media Layer
s,3
Media maintains a minimum filtration rate of 5
in/hr over lifetime of facility. An initial
filtration rate of 8 to 12 in/hr is recommended
to allow for clogging over time; the initial
filtration rate should not exceed 12 inches per
hour.

A filtration rate of at least 5 inches per
hour allows soil to drain between events.

The initial rate should be higher than
long term target rate to account for
clogging over time. However an
excessively high initial rate can have a
negative impact on treatment
performance, therefore an upper limit is
needed.

Media is a minimum 18 inches deep, meeting
either of these two media specifications:

City of San Diego Low Impact Development
Design Manual (page B-18) (July 2011, unless
superseded by more recent edition) or County
of San Diego Low Impact Development
Handbook: Appendix G -Bioretention Soil
Specification Dune 2014, unless superseded by
more recent edition).

Alternatively, for proprietary designs and
custom media mixes not meeting the media
specifications contained in the City or County
LID Manual, the media meets the pollutant
treatment performance criteria in Section F.1.

A deep media layer provides additional
filtration and supports plants with deeper
roots.

Standard specifications shall be followed.

For non-standard or proprietary designs,
compliance with F.1 ensures that
adequate treatment performance will be
provided.

E-70
08/11/2026 PH2
February 2016
562 of 876

Appendix E: BMP Design Fact Sheets
Siting and Design
Intent/Rationale
Media surface area is 3% of contributing area
times adjusted runoff factor or greater. Unless
demonstrated that the BMP surface area can
be smaller than 3%.

Greater surface area to tributary area
ratios: a) maximizes volume retention as
required by the MS4 Permit and b)
decrease loading rates per square foot
and therefore increase longevity.

Adjusted runoff factor is to account for
site design BMPs implemented upstream
of the BMP (such as rain barrels,
impervious area dispersion, etc.). Refer
to Appendix B.2 guidance.

Use Worksheet B.5-1 Line 26 to estimate
the minimum surface area required per
this criteria.

Where receiving waters are impaired or have a
TMDL for nutrients, the system is designed
with nutrient sensitive media design (see fact
sheet BF -2).

Potential for pollutant export is partly a
function of media composition; media
design must minimize potential for
export of nutrients, particularly where
receiving waters are impaired for
nutrients.

Filter Course Layer
A filter course is used to prevent migration of
fines through layers of the facility. Filter fabric
is not used.

Migration of media can cause clogging of
the aggregate storage layer void spaces or
subgrade. Filter fabric is more likely to
clog.

Filter course is washed and free of fines.

Washing aggregate will help eliminate
fines that could clog the facility and
impede infiltration.

Filter course calculations assessing suitability
for particle migration prevention have been
completed.

Gradation relationship between layers
can evaluate factors (e.g., bridging,
permeability, and uniformity) to
determine if particle sizing is appropriate
or if an intermediate layer is needed.

Aggregate Storage Layer
Class 2 Permeable per Caltrans specification
68-1.025 is recommended for the storage layer.

Washed, open -graded crushed rock may be
used, however a 4-6 inch washed pea gravel
Washing aggregate will help eliminate
fines that could clog the aggregate
storage layer void spaces or subgrade.
08/11/2026
E-71
PH2
February 2016
563 of 876

Appendix E: BMP Design Fact Sheets
Siting and Design
Intent/Rationale
filter course layer at the top of the crushed
rock is required.

The depth of aggregate provided (12 -inch
typical) and storage layer configuration is
adequate for providing conveyance for
underdrain flows to the outlet structure.

Proper storage layer configuration and
underdrain placement will minimize
facility drawdown time.

Inflow, Underdrain, and Outflow Structures
Inflow, underdrains and outflow structures are
accessible for inspection and maintenance.

Maintenance will prevent clogging and
ensure proper operation of the flow
control structures.

Inflow velocities are limited to 3 ft./s or less or
use energy dissipation methods. (e.g., riprap,
level spreader) for concentrated inflows.

High inflow velocities can cause erosion,
scour and/or channeling.

Curb cut inlets are at least 12 inches wide, have
a 4-6 inch reveal (drop) and an apron and
energy dissipation as needed.

Inlets must not restrict flow and apron
prevents blockage from vegetation as it
grows in. Energy dissipation prevents
erosion.

Underdrain outlet elevation should be a
minimum of 3 inches above the bottom
elevation of the aggregate storage layer.

A minimal separation from subgrade or
the liner lessens the risk of fines entering
the underdrain and can improve
hydraulic performance by allowing
perforations to remain unblocked.

Minimum underdrain diameter is 6 inches.

Smaller diameter underdrains are prone
to clogging.

Underdrains are made of slotted, PVC pipe
conforming to ASTM D 3034 or equivalent or
corrugated, HDPE pipe conforming to
AASHTO 252M or equivalent.

Slotted underdrains provide greater
intake capacity, clog resistant drainage,
and reduced entrance velocity into the
pipe, thereby reducing the chances of
solids migration.

An underdrain cleanout with a minimum 6 -
inch diameter and lockable cap is placed every
250 to 300 feet as required based on
underdrain length.

Properly spaced cleanouts will facilitate
underdrain maintenance.

Overflow is safely conveyed to a downstream
storm drain system or discharge point Size
overflow structure to pass 100 -year peak flow
Planning for overflow lessens the risk of
property damage due to flooding.
08/11/2026
E-72
PH2
February 2016
564 of 876

Appendix E: BMP Design Fact Sheets
Siting and Design Intent/Rationale
for on-line infiltration basins and water quality
peak flow for off-line basins.

Conceptual Design and Sizing Approach for Storm Water Pollutant Control Only To design bioretention with underdrain for storm water pollutant control only (no flow control required), the following steps should be taken:

1. Verify that siting and design criteria have been met, including placement requirements, contributing tributary area, maximum side and finish grade slopes, and the recommended media surface area tributary ratio.

2. Calculate the DCV per Appendix B based on expected site design runoff for tributary areas.

3. Use the sizing worksheet presented in Appendix B.5 to size biofiltration BMPs.

Conceptual Design and Sizing Approach when Storm Water Flow Control is Applicable Control of flow rates and/or durations will typically require significant surface ponding and/or aggregate storage volumes, and therefore the following steps should be taken prior to determination of storm water pollutant control design. Pre -development and allowable post -project flow rates and durations should be determined as discussed in Chapter 6 of the manual.

2. Iteratively determine the facility footprint area, surface ponding and/or aggregate storage layer depth required to provide detention storage to reduce flow rates and durations to allowable limits. Flow rates and durations can be controlled from detention storage by altering outlet structure orifice size(s) and/or water control levels. Multi -level orifices can be used within an outlet structure to control the full range of flows.

3. If bioretention with underdrain cannot fully provide the flow rate and duration control required by this manual, an upstream or downstream structure with significant storage volume such as an underground vault can be used to provide remaining controls.

4. After bioretention with underdrain has been designed to meet flow control requirements, calculations must be completed to verify if storm water pollutant control requirements to treat the DCV have been met.
08/11/2026
E-73
PH2
February 2016
565 of 876

Appendix E: BMP Design Fact Sheets
E.13 BF -2 Nutrient Sensitive Media Desigr
Some studies of bioretention with underdrains have observed export of nutrients, particularly inorganic nitrogen (nitrate and nitrite) and dissolved phosphorus. This has been observed to be a short-lived phenomenon in some studies or a long term issue in some studies. The composition of the soil media, incluc ing the chemistry of individual elements is believed to be an important factor in the potential for nutrient export. Organic amendments, often compost, have been identified as the most likely source of nutrient export. The quality and stability of organic amendments can vary widely.

The biofiltration media specifications contained in the County of San Diego Low Impact Development Handbook: Appendix G -Bioretention Soil Specification (June 2014, unless superseded by more recent edition) and the City of San Diego Low Impact Development Design Manual (page B-18) (July 2011, unless superseded by more recent edition) were developed with consideration of the potential for nutrient export. These specifications include criteria for individual component characteristics and quality in order to control the overall quality of the blended mixes. As of the publication of this manual, the June 2014 County of San Diego specifications provide more detail regarding mix design and quality control.

The City and County specifications noted above were developed for general purposes to meet permeability and treatment goals. In cases where the BMP discharges to receiving waters with nutrient impairments or nutrient TMDLs, the biofiltration media should be designed with the specific goal of minimizing the potential for export of nutrients from the media. Therefore, in addition to adhering to the City or County media specifications, the following guidelines should be followed:

1. Select plant palette to minimize plant nutrient needs A landscape architect or agronomist should be consulted to select a plant palette that minimizes nutrient needs. U-i izing plants with low nutrient needs results in less need to enrich the biofiltration soil mix. If nutrient quantity is then tailored to plants with lower nutrient needs, these plants will generally have less competition from weeds, which typically need higher nutrient content. The following practices are recommended to minimize nutrient needs of the plant palette:
• Utilize native, drought -tolerant plants and grasses where possible. Native plants generally have a broader tolerance for nutrient content, and can be longer lived in leaner/lower nutrient soils.
• Start plants from smaller starts or seed. Younger plants are generally more tolerant of lower nutrient levels and tend to help develop soil structure as they grow. Given the lower cost of smaller plants, the project should be able to accept a plant mortality rate that is somewhat higher than starting from larger plants and providing high organic content.

2. Minimize excess nutrients in media mix
Once the low -nutrient plant palette is established (item 1), the landscape architect and/or agronomist should be consulted to assist in the design of a biofiltration media to balance the interests of plant 08/11/2026
E-74
PH2
February 2016
566 of 876

Appendix E: BMP Design Fact Sheets
establishment, water retention capacity (irrigation demand), and the potential for nutrient export. The following guidelines should be followed:
• The mix should not exceed the nutrient needs of plants. In conventional landscape design, the nutrient needs of plants are often exceeded intentionally in order to provide a factor of safety for plant survival. This practice must be avoided in biofiltration media as excess nutrients will increase the chance of export. The mix designer should keep in mind that nutrients can be added later (through mulching, tilling of amendments into the surface), but it is not possible to remove nutrients, once added.
• The actual nutrient content and organic content of the selected organic amendment source should be determined when specifying mix proportions. Nutrient content (i.e., C:N ratio; plant extractable nutrients) and organic content (i.e., % organic material) are relatively inexpensive to measure via standard agronomic methods and can provide important information about mix design. If mix design relies on approximate assumption about nutrient/organic content and this is not confirmed with testing (or the results of prior representative testing), it is possible that the mix could contain much more nutrient than intended.
• Nutrients are better retained in soils with higher cation exchange capacity. Cation exchange capacity can be increased through selection of organic material with naturally high cation exchange capacity, such as peat or coconut coir pith, and/or selection of inorganic material with high cation exchange capacity such as some sands or engineered minerals (e.g., low P -index sands, zeolites, rhyolites, etc.). Including higher cation exchange capacity materials would tend to reduce the net export of nutrients. Natural silty materials also provide cation exchange capacity; however potential impacts to permeability need to be considered. • Focus on soil structure as well as nutrient content. Soil structure is loosely defined as the ability of the soil to conduct and store water and nutrients as well as the degree of aeration of the soil. Soil structure can be more important than nutrient content in plant survival and biologic health of the system. If a good soil structure can be created with very low amounts of organic amendment, plants survivability should still be provided. While soil structure generally develops with time, biofiltration media can be designed to promote earlier development of soil structure. Soil structure is enhanced by the use of amendments with high humus content (as found in well -aged organic material). In addition, soil structure can be enhanced through the use of organic material with a distribution of particle sizes (i.e., a more heterogeneous mix). • Consider alternatives to compost. Compost, by nature, is a material that is continually evolving and decaying. It can be challenging to determine whether tests previously done on a given compost stock are still representative. It can also be challenging to determine how the properties of the compost will change once placed in the media bed. More stable materials such as aged coco coir pith, peat, biochar, shredded bark, and/or other amendments should be considered.

With these considerations, it is anticipated that less than 10 percent organic amendment by volume 08/11/2026
E-75
PH2
February 2016
567 of 876

Appendix E: BMP Design Fact Sheets
could be used, while still balancing plant survivability and water retention. If compost is used, designers should strongly consider uti i7ing less than 10 percent by volume.

3. Design with partial retention and/or internal water storage An internal water storage zone, as described in Fact Sheet PR -1 is believed to improve retention of nutrients. For lined systems, an internal water storage zone worked by providing a zone that fluctuates between aerobic and anaerobic conditions, resulting in nitrification/denitrification. In soils that will allow infiltration, a partial retention design (PR -1) allows significant volume reduction and can also promote nitrification/denitrification.

Acknowledgment: This fact sheet has been ada'pted from the Orange County Technical Guidance Document (May 2011;. It was originally developed based on input from: Deborah Deets, City of Los Angeles Bureau of Sanitation, Drew Ready, Center for Watershed Health, Rick Fisher, ASLA, City of Los Angeles Bureau of Engineering, Dr. Garn Wallace, Wallace Laboratories, Glen Dake, GDML, and: ason Schmidt, Tree People. The guidance'provided herein does not reflect the individual o pinions of any individual listed above and should not be cited or otherwise attributed to those listed. 08/11/2026
E-76
PH2
February 2016
568 of 876

O
co
-3
-3
N
O
Q
0 C
O
0 C
CD
n
N
90 Z
91840 699
(•
n
O
3 • • • O
POO_
l ( D
5 f)
O O n,
�VJ
U) (D
ct
(0 —F)
O
C
• • •
• • •
. •

Aquasave is an underground modular tank system designed to retain, store, and/or infiltrate stormwater. Made from recycled plastics, Aquasave has over a 90% void space and is ideal for creating tanks for any of three desired purposes:
• Traditional Storage System: The tank is wrapped in a
woven or non -woven geotextile and pipes are connected
via pipe -boots directly to the tank.
• Infiltration System: The tank is wrapped in a microgrid mesh liner which allows the free flow of water from the tank into permeable soils.
• Rain Harvesting System: The tank is wrapped in 30mi1
visqueen and then sealed. A pump is installed, and this water can be used for irrigation.

C
CO
O
CO
.C
L
cd
O
E
co
7O
.>
D
0 a)
.L
a
E
0 . U)
ate)
U)
ai
.
3)
CCi
a)
C-
U
O
3)
Cd
O
a)
. a)
coTi
>
cd
C
a)
Cd
Q
Cd
a)
U
Cd
U)
ID
C
O
Ial

rd
E
C-
a)
(0
3)
a
E
.U)
a)
0 E
0 Cd
a)
(d
a)
H
a)
7a
D
5 C
. Cd
O)
Cd
U
O
Cd
C
0 0)
I
j)
C
O
E
c
.>
U)
0 co
a)
LE
a)
CO
C-
.C
C
0 a
U)
ai
a)
.U)
N
a
a)
u)
a)
D
(l
C-
a)
L
U)
0 TO
. U)
a)
ai
al
CO
0 a)
a
E
0 C
O
a
_a)
7a
al
.Cd
Cd
U)
Cd
Q
D
C -
LE
(d
a)
7O
.>
0 a
Cd
0)
U)
H
H
Q
a)
E
C-
a)
3)
0 U)
CT
a)
C-
0)
Cd
C
O
13 .>
0 a
0 (d
0)
C
.C
. co
C
O
O
c_
CO
C
U
0_
C
a)
E
U
Cl
Q
(d
3)
E
0 Cd
C-
a
0 a
a)
U)
aa))
0 C-
0o
L
C
0 P
U)
U
Cd
a)
C-
o
(0
a)
TO
.C
a)
cd
c_
a
U
Cd
N
C
.Cd
2 . . .

CO
N
0 N
N-

Aquasave
8053 & 8025 Modules
Aquasave 8053
Length Width Height

31.8" 19.4" 21"

2.65' 1.61667' 1.75'
Storage Volume 6.75 cf
Aquasave 8025
Length Width Height

31.8" 19.4" 10"

2.65' 1.61667' 0.8333'
Storage Volume 3.21 cf
AS 8053
Storage Volume (cf)
Height of Module (inches)
AS8053-1
675
21 AS8053-2

13.50 41.25
AS8053-3

20.24 81.5
AS8053-4
2699

81.75 AS8053-5

33.74 102
AS 8025
AS8025 - 1

3.21 10
AS8025 - 2

6.43 19.25
AS8025 - 3

9.64 28.5
AS8025 - 4

12.85 37.75
AS8025 - 5

16.07 47
AS 8025 - 6

19.28 56.25
AS8025 - 7

22.49 65.5
AS8025 - 8
2571

74.75 AS8025 - 9

28.92 84
A58025 -10

32.13 93.25
A distributor of Aquasave Tanks:

California Filtration Specialists, LLC
640 Alpine Way e.

Escondido, CA 92029 / i
858-705-6483
r ItiB18
www.cafiltrationspecialists.com
1CFSI
info�a cafiltrationspecialists.com
08/11/2026 A distributor of Aquagb Tanks in CA, AZ & NV 572 of 876

DMA -2.2 IS SWAPPED TO BE TREATED
IN EXCHANGE FOR DMA -2.1 THAT WON'T BE TREATED
Automated Worksheet B.1: Calculation of Design rapture Volume (V2.0 CategorM
Description
i
Units
ill 1
Drainage Basin ID or Name
DMA -2.1
DMA -2.2
nitless
2 85th Percentile 24 -hr Storm Depth

0.66 0.66
inches
3 Impervious Surfaces Not Directed to Dispersion Area (C=0.90) 830
1,950
sq-ft
Standard
4 Semi -Pervious Surfaces Not Serving as Dispersion Area (C=0.30) sq-ft
Drainage Basin
5 Engineered Pervious Surfaces Not Serving as Dispersion Area (C=0.10) sq-ft
Inputs
6 Natural Type A Soil Not Serving as Dispersion Area (C=0.10) sq-ft
7 Natural Type B Soil Not Serving as Dispersion Area (C=0.14) sq-ft
8 Natural Type C Soil Not Serving as Dispersion Area (C=0.23) sq-ft
9 Natural Type D Soil Not Serving as Dispersion Area (C=0.30) 3,271
sq-ft
MI
0 Does Tributary Incorporate Dispersion, Tree Wells, and/or Rain Barrels? No
No
yes/no
11 Impervious Surfaces Directed to Dispersion Area per SD -B (Ci=0.90) sq-ft
12 Semi -Pervious Surfaces Serving as Dispersion Area per SD -B (Ci=0.30) sq-ft
13 Engineered Pervious Surfaces Serving as Dispersion Area per SD -B (Ci=0.10) sq-ft
Dispersion
Area, Tree Well
& Rain Barrel
Inputs
14 Natural Type A Soil Serving as Dispersion Area per SD -B (Ci=0.10) sq-ft
15 Natural Type B Soil Serving as Dispersion Area per SD -B (Ci=0.14) sq-ft
16 Natural Type C Soil Serving as Dispersion Area per SD -B (Ci=0.23) sq-ft
(Optional)
17 Natural Type D Soil Serving as Dispersion Area per SD -B (Ci=0.30) sq-ft
18 Number of Tree Wells Proposed per SD -A
#
19 Average Mature Tree Canopy Diameter
ft
20 Number of Rain Barrels Proposed per SD -E
#
21 Average Rain Barrel Size
gal
22 Total Tributary Area
4,101
1,950
sq-ft
Initial Runoff
23 Initial Runoff Factor for Standard Drainage Areas

0.42 0.90
unitless
Factor
Calculation
24 Initial Runoff Factor for Dispersed & Dispersion Areas

0.00 0.00
unitless
25 Initial Weighted Runoff Factor

0.42 0.90
unitless
26 Initial Design Capture Volume
95 97
cubic -feet
27 Total Impervious Area Dispersed to Pervious Surface
0 0
sq-ft
Dispersion
Area
Adjustments
28 Total Pervious Dis. ersion Area
-
0 0
sq-ft
29 Ratio of Dispersed Impervious Area to Pervious Dispersion Area n/a
n/a
ratio
30 Adjustment Factor for Dispersed & Dispersion Areas

1.00 1.00
ratio
31 Runoff Factor After Dispersion Techniques

0.42 0.90
unitless
32 Design Capture Volume After Dispersion Techniques
95 97
cubic -feet
Tree & Barrel
33 Total Tree Well Volume Reduction
0 0
cubic -feet
Adjustments
34 I
Total Rain Barrel Volume Reduction
0 0
cubic -feet
35 Final Adjusted Runoff Factor

0.42 0.90
unitless
Results
36 Final Effective Tributary Area
1,722
1,755
sq-ft
37 Initial Design Capture Volume Retained by Site Design Elements 0 0
cubic -feet
38 Final Design Capture Volume Tributary to BMP
95 97
cubic -feet
No Warning Messages

THIS DCV IS PROVIDED IN SSD-BMP

WORKSHEET FOR TREEWELL DESIGN
08/11/2026
PH2 573 of 876

9Z0Z/ I. 1. /80
919 40 1719
SSD-BMP Autom ated Worksheet I-1: Step 1. C alcul ation of Design C apture Volume (V1.0) Cat -:

i
Units
lir
1 Drainage Basin ID or Name
DMA 2.2+2 .3
a rtless
PIE
2 85th Percentile 24 -hr Storm Depth

0.66 inches
3 Is Hydrom odifi cation C ontrol Applicable?
No
yes/no
Standard
Drainage Basin
Inputs
4 Impervi ous Surfaces Not Directed to Dispersion Area (C=0.90) 3,291
sq-ft
5 Semi -Pervious Surfaces Not Serving as Dispersion Area (C=0.30) sq-ft
6 Engineered Pervious Surfaces Not Serving as Dis Dersion Area (C=0.10) sq-ft
7 N atural Typ e A Soil Not Serving as Dispersion Area (C=0.10) sq-ft
8 Natural Type B S oil N ot Ser ving as Dis persion Area (C=0.14) sq-ft
9 Natural Type C Soil Not Serving as Dispersion Area (C=0.23) sq-ft
10 Natur al Type D Soil Not Serving as Dispersion Ar ea (C=0.30) sq-ft
SSD -BMPs
11 Does Tributary Inc orporate Dispersion and/or Rain Barrels? yes/no
Proposed
12 Do es Tribut ary Incorporate Tre e Wells?
yes/no
13 Impervious Surfaces D ire cted to Dispersion Ar ea per SD -B (Ci=0 .90) sq-ft
14 Semi -Pervious Surfaces S erving as Dispersion Area per SD -B (Ci=0 .30) sq-ft
Dispe rsion Area
& R ain Ba rrel
Inputs
15 Engineered P ervious Surfaces S er ving as Disp ersion Area per SD -B (Ci=0 .10) sq-ft
16 Natural Type A Soil S erving as Dispersion Area per SD -B (Ci=0 .10) sq-ft
17 Natur al Type B Soil Ser ving as Disp ersion Area per SD -B (Ci=0 .14) sq-ft
(Optiona l)
hoill
18 Natural Type C Soil Serving as Dispersion Ar ea per SD -B (Ci=0 .23) sq-ft
19 Natural Type D Soil Serving as Disp ersion Area per SD -B (Ci=0 .30) sq-ft
20 Numb er of Rain B arrels Proposed per SD -E
#
21 Average Rain Barrel Size
gal
22 Total Tributary Ar ea
3,291
sq-ft
Initial Runoff
23 Initial Runoff Factor for Standard Drainage Areas

0.90 unitless
Factor
24 Initial Runoff Factor for Dispersed & Dispersion Areas

0.00 unitiess
Calc ulation
25 Initi al Weighted Runoff Factor
0 .90
unitless
I nitial Design Capt ure Volume
163
cubic -feet
MI26
Dispe rsion A rea
Adjustment &
Rain Ba rrel
27 Tota l Impervious Are a Dispersed to Per vious Surface 0 sq-ft
28 Total Pervious Dispersion Area
0 sq-ft
29 Ratio of Dispersed Impervious Area to Pervious Dispersion Area for DCV Reducti on n/a
ratio
30 Adjustment Factor for Dispersed & Dispersion Areas
1 .00
ratio
Adjustment
31 Runoff Factor After Dispersion Techniques

0.90 unitiess
32 Design Capture Volume After Dispersion Techniques
163
cubic -feet
33 To tal Rain Barrel Volume Reduction
0 cubic -f eet
34 Final Adjusted Runoff Factor

0.90 unitless
esults
35 Final E ffective Tributary Ar ea
2,962
sq-ft
36 Initial Design Capture Vo lu me Retained by Dispersion Area and Rain Barrel(s) 0 cubic -feet
37 R emaining Design Capture Volume Tributary to Tree Well(s) 163
cubi c -feet

9Z0Z/ I. 1. /80
919 40 9L9
SSD- BMP Automated Worksheet I-3: Step 3. Tree Well Sizing (V1 .0) tegory
ili_dab iliai
& Units
1 Drainage Basin ID or Name
DMA 2 .2+2.3
unitless
2 Design Capture Volume Tributary to BMP
163
cubic -feet
3 Is Hydr omodification Control Applicable?
No
yes/no
4 Predominant NRCS Soil Type Within Tr ee W ell(s) Lo cation D
unitless
Standard Tree
Well Inputs
5 Select a Tree Species for the Tree Well(s) Consistent with SD -A Tree Palette Table Numbers shown in list are Tree Species Mat ure Canopy Di ameters 20' - Other
unitless
6 Tree Well(s) S oil Depth (Installation Depth)
Must be 30, 36, 42, or 48 Inches; Select fr om Standard Depths** a
inches
7 Number of Identical* Tr ee Wells Pr oposed for this DMA 1 trees
8 Prop osed Width of Tree Well(s) Soil Installation for One (1) Tree

5.5 feet
9 Pr op osed Length of Tree Well(s) S oil Installati on for One (1) Tree 29 .0
feet
10 B otanical Name of Tr ee Species
Pr oSWQinPDP
QMP
unitless
Tree Data
11 Tr ee Species Mature H eight per SD -A
ProSW e�i�nDP
4Pp
feet
12 Tree Species Mature Can opy Diameter per SD -A
20 feet
13 Minimum S oil V olume Required In Tree Well
(2 Cubic Feet Per Square Foot of Mat ure Tree Canopy Pr ojection Area) 628
cubic -feet
14 Cr edit Volum e P er Tre e
180
cubi c -fe et
15 DCV Multiplier To Meet Flow C ontrol Requirements
n/a
unitless
16 Re quired Re tention Volume (RRV) To M eet Flow Control R equirements n/a
cubic -f eet
17 N umber of Trees Required
1 trees
18 Total Area of Tree Well Soil Required for Each Tree
157
sq-ft
Tre e Well Sizing
19 Appro ximate Required Width of Tree Well Soil Area f or Each Tree 13 feet
Calcula tio ns
20 Approximate Required Length of Tree Well Soil Area for Each Tree 13 feet
21 Nu mber of Trees Prop osed for this DMA
1 trees
22 Total Area of Tree Well Soil Proposed for Each Tr ee 160
sq-ft
ilim
23 Minimum Spacing Between Multiple Trees To Meet Soil Area Requirements (when applicable)***
n/a
feet
24 Are Tree Well Soil Installa tion R equirements Met?
Yes
yes/no
Results
25 Is Remaining DCV R equireme nt Fully Satisfied by Tree Well(s)? Yes
yes/no
26 Is Hydromodific ation Control Requireme nt Satisfie d by Tree We ll(s)? n/a
yes/no

SD -A Tree Well
E.1 SD -A Tree WeII
MS4 Permit Category
Site Design
Retention
Manual Category
Site Design
Infiltration
Applicable Performance
Standard
Site Design
Pollutant Control
Flow Control
Primary Benefits
Volume Reduction
(Source: County of San Diego LID Manual — EOA, Inc.)
Description
Trees planted to intercept rainfall and runoff as described in this fact sheet may be used as storm water management measures to provide runoff reduction of the DCV per Appendix B.1.4. Additional benefits associated with tree wells, include energy conservation, air quality improvement, and aesthetic enhancement. Tree wells located in the City's Right -of -Way are subject to the discretion of City Engineer and Parks and Recreation Director. Typical storm water management benefits associated with trees include:
• Treatment of storm water — Storm water from impervious area should be directed to the tree wells. Trees provide treatment through uptake of nutrients and other storm water pollutants (phytoremediation) and support of other biological processes that break down pollutants
• Interception of rainfall — tree surfaces (roots, foliage, bark, and branches) intercept, evaporate, store, or convey precipitation to the soil before it reaches surrounding impervious surfaces
• Reduced erosion — trees protect denuded area by intercepting or reducing the velocity of rain drops as they fall through the tree canopy
• Increased infiltration — soil conditions created by roots and fallen leaves promote infiltration 08/11/2026
EFH2

SD -A Tree Well
Typical tree well system components include:
• Directing runoff from
impervious areas through a
drainage opening into a tree well
planting area.
• Trees of the appropriate species
for site conditions and
constraints. Refer to the Plant
List fact sheet (Appendix E.21).
• Available soil media reservoir
volume based on mature tree size,
soil type, water availability,
surrounding land uses, and
project goals
• Optional suspended pavement
design to provide structural
support for adjacent pavement
without requiring compaction of underlying layers

CURB CURB CUT

OPTIONAL
GRATE
RUNOFF m
/ INLET
%��f��

SIDEWALK SECTION

PAVEMENT

SECTION
SURFACE1PONDIN REA DISTRIBUTION LAYER
o o o o o o o o o o o o o o o o
o ° o ° ° ° o ° 0 O ° ° ° ° °
0 0 0 0 00 0 000 0 0 00 0 0
° ° ° ° °

OO O O OO O O OO O O OO O O
° ° ° ° ° ° °

O O O O O OO OO O
°°
0 0 0° TREE WELL SOIL o° o° ° ° °
O°0 0 0 0
° ° ° ° ° .. ° ° °

O O O O O O O O O OO OO OO O
o ° ° ° OPTIONAL ° °
O O O O° ° ° ° ° °
0 0 0 0 000 0 0
o 0 o 0 O O O o UNDERDRAIN o
O O O 0 00 O O 00.0 O O O O O
O 0 0 0 O O O O ..
v W
w W W V V W W w W

W W W W W W W W W W

W W V V W W W W W

W W W NATIVE SOIL W W

W W W W
W W W V w W
W W W W W w w W

W W V W W W W
W W w w OPTIONAL W w
W w v BARRIER W „ W
C 5
OO 0 0 O 0 0 O 0 0 ° 0 ° O O
Schematic of Tree Well
• Optional root barrier devices as needed; a root barrier is a device installed in the ground, between a tree and the sidewalk or other structures, intended to guide roots down and away from the sidewalk or structures in order to prevent damage from tree roots. • Optional tree grates; to be considered to maximize available space for pedestrian circulation and to protect tree roots from compaction related to pedestrian circa ation; tree grates are typically made up of porous material that will allow the runoff to soak through. • Optional shallow surface depression for ponding of excess runoff • Optional planter box underdrain
Design Adaptations for Project Goals
Site design BMP to provide incidental treatment. Tree wells primarily functions as site design BMPs for incidental treatment.

Storm water pollutant control BMP to provide treatment. Project proponents are allowed to design tree wells to reduce the volume of stormwater runoff that requires treatment, (the Design Capture Volume [DCV]), or completely ful=l the pollutant control BMP requirements by retaining the entire DCV. Benefits from tree wells are accounted for by using the volume reduction values in Table B.1-3 presented in Appenr ix B. This credit can apply to other trees that are used for landscaping purposes that meet the same criteria. Project proponents are required to provide calculations supporting the amount of credit claimed from implementing trees within the project footprint. Tree wells designed to completely ful=l the pollutant control BMP requirements by retaining the entire 08/11/2026
EF4H2
57i o

SD -A Tree Well
DCV are designated as SSD-BMPs and located in Appendix I.

Flow Control BMP to meet hydromodification requirements. Project proponents are also allowed to design tree wells as a flow control BMP. Benefits from tree wells are accounted for by using the DCV multipliers listed in Appendix I. Project proponents are required to provide calculations showing that the entire DCV including the DCV multiplier is retained.

Design Criteria and Considerations
Tree Wells, whether designed as Site Design BMPs, as Stormwater Pollutant Control BMP, or as a Flow Control BMP must meet the following design criteria and considerations, and if placed in the right-of-way must be consistent with the County of San Diego Green Streets Standard Drawings.

Deviations from the below criteria may be approved at the discretion of the City Engineer if it is determined to be appropriate:

Siting and Design
Intent/Rationale
Tree species is appropriately chosen for the
development (private or public). For public
rights -of -ways, city planning guidelines and
zoning provisions for the permissible species
and placement of trees are consulted. A list of
trees appropriate for site design are provided in
Appendix E.21
Proper tree placement and species
selection minimizes problems such as
pavement damage by surface roots and
poor growth.

Tree well placement: ensure area is graded;
and the well is located so that full amount of
DCV reduction drains to well.

Minimizes short-circuiting of run off and
assures DCV reductions are retained
onsite.

Location of trees planted along public streets
follows city requirements and guidelines.

Vehicle and pedestrian line of sight are
considered in tree selection and placement.

Location of trees planted within private
development follows city landscape guidelines.

Building setbacks, utility alignments, vehicle
and pedestrian line of sight are considered in
tree selection and placement.

Unless otherwise approved by the City
Engineer the following minimum tree
separation distance is followed
Roadway safety for both vehicular and
pedestrian traffic is a key consideration
for placement along public streets.
08/11/2026
EF5H2 578Jo �o

SD -A Tree Well
Siting and Design
Improvement
Traffic Signal, Stop sign
Underground Utility lines
(except sewer)
Sewer Lines
Above ground utility
structures (Transformers,
Hydrants, Utility poles, etc.)
Driveways
Intersections (intersecting
curb lines of two streets)
Minimum
distance to
Tree Well
20 feet
5 feet
10 feet
10 feet
10 feet
25 feet
Intent/Rationale
Underground utilities and overhead wires
are considered in the design and avoided or
circumvented. Underground utilities are routed
❑ around or through the planter in suspended
pavement applications. All underground
utilities are protected from water and root
penetration.

Tree growth can damage utilities and
overhead wires resulting in service
interruptions. Protecting utilities routed
through the planter prevents damage and
service interruptions.

Suspended pavement is used for confined
Tree Well soil volume. Suspended pavement
design was developed where appropriate to
minimize soil compaction and improve
infiltration and filtration capabilities.

Suspended pavement was constructed with an
approved structural cell.

Suspended pavement designs provide
structural support without compaction
of the underlying layers, thereby
promoting tree growth.

Recommended structural cells include
poured in place concrete columns, Silva
Cells manufactured by Deeproot Green
Infrastructures and Stratacell and
Stratavault systems manufactured by
Citygreen Systems or approved equal.

Suspended pavement shall not be used
within the city's right-of-way and
easements.

A minimum soil volume of 2 cubic feet per
square foot of canopy projection volume is
provided for each tree. Canopy projection area
The minimum soil volume ensures that
there is adequate storage volume to
allow for unrestricted evapotranspiration
and infiltration.
08/11/2026
EPH2 5740t �°

SD -A Tree Well
Siting and Design
Intent/Rationale
is the ground area beneath the tree, measured at
the drip line. Soil volume must be within 1.5
times the mature tree canopy radius. Soil depth
shall be a minimum of 30 inches deep,
preferably 36 inches deep. When placing tree
well next to curbs or other structures use
Structural Soil as outlined in the section below
titled "Confined Tree Well Soil Volume". Use
Amended Soil per Fact Sheet SD -F in all other
cases.

DCV from the tributary area draining to the
tree is equal to or greater than the tree credit
volume
The minimum tributary area ensures that
the tree receives enough runoff to fully
uti i7e the infiltration and
evapotranspiration potential provided. In
cases where the minimum tributary area
is not provided, the tree credit volume
must be reduced proportionately to the
actual tributary area.

Inlet opening to the tree that is at least 18
inches wide.

A minimum 2 inch drop in grade from the inlet
to the finish grade of the tree.

Grated inlets are allowed for pedestrian
circulation. Grates need to be ADA compliant
and have sufficient slip resistance.

Design requirement to ensure that the
runoff from the tributary area is not
bypassed.

Different inlet openings and drops in
grade may be allowed at the discretion of
the City Engineer if calculations are
shown that the diversion flow rate
(Appendix B.4.4) from the tributary area
can be conveyed to the tree. In cases
where the inlet capacity is limiting the
amount of runoff draining to the tree,
the tree credit volume must be reduced
proportionately.

Conceptual Design and Sizing Approach for Site Design
Determine the areas where tree wells can be used in the site design to achieve incidental treatment.

Tree wells reduce runoff volumes from the site. Refer to Appendix B.1. Document the proposed tree locations in the SWQMP.

For conceptual design and sizing approach for pollutant control and flow control, refer to Appendix I.
08/11/2026
E�H2 580T o

SD -A Tree Well
Tree Planting Design in New or Reconstructed Streetscapes

1. Maximized open soil area for tree planting is the most cost effective method of achieving the required soil volume.

2. Tree wells within sidewalks shall have a minimum open area of four feet wide by six feet long. Larger areas may be required to accommodate large root balls.

3. Tree well soil characteristics shall meet the requirements of SD -F Amended Soil.

Structural Requirements for Confined Tree Well Soil Volume In order to provide adequate soil volume for tree wells, soils may be placed confined beneath adjacent paved surfaces. Acceptable soil systems capable of carrying D-50 loading include structural soils, structural slabs, and structural cells:

1. Structural soil systems include CU-StructuralSoil', Stalite Structural Soil, or equivalent.

2. Suspended pavements that allow uncompacted growing soil beneath the sidewalk include; structural slabs that span between structural supports, structural cells, and other commercially available structural systems. Manufacturer details and certification must be provided for commercial systems. Structural calculations and details must be provided for structural slab installations. Structural cells are commercially -available structural systems placed subsurface that support the sidewalk and are filled with amended soil (SD -F).

Manufacturer details and certification must be provided for commercial systems.

Suspended pavement shall not be used within the city's right-of-way and easements.

Stormwater Retention and Treatment Volume
Tree wells with expanded soil volume will serve as a method of capturing and retaining the required volume of stormwater in accordance with City requirements in Appendix B of this manual. These facilities can be designed to meet the City requirements when surface ponding volume is provided, whether designed as an enclosed plant bed with covered soil volume, or a continuous open area (either mulched or with turf) with soil volume under the adjacent sidewalk.

Maintenance Overview
Normal Expected Maintenance. Tree health shall be maintained as part of normal landscape maintenance. Additionally, ensure that storm water runoff can be conveyed into the tree well as designed. That is, the opening that allows storm water runoff to flow into the tree well (e.g., a curb opening, tree grate, or surface depression) shall not be blocked, ed, re -graded, or otherwise changed in a manner that prevents storm water from draining into the tree well. A summary table of standard inspection and maintenance indicators is provided within this Fact Sheet.

Non -Standard Maintenance or BMP Failure. Trees wells are site design BMPs that normally do not require maintenance actions beyond routine landscape maintenance. The normal expected 08/11/2026
EPH2 58i tit

SD -A Tree Well
maintenance described above ensures the BMP functionality. If changes have been made to the tree well entrance / opening such that runoff is prevented from draining into the tree well (e.g., a curb inlet opening is blocked by debris or a grate is clogged causing runoff to flow around instead of into the tree well, or a surface depression has been filled so runoff flows away from the tree well), the BMP is not performing as intended to protect downstream waterways from pollution and/or erosion.

Corrective maintenance will be required to restore drainage into the tree well as designed.

Surface ponding of runoff directed into tree wells is expected to infiltrate/evapotranspire within 24- 96 hours following a storm event. Surface ponding longer than approximately 24 hours following a storm event may be detrimental to vegetation health, and surface ponding longer than approximately 96 hours following a storm event poses a risk of vector (mosquito) breeding. Poor drainage can result from clogging or compaction of the soils surrounding the tree. Loosen or replace the soils to restore drainage.

Other Special Considerations. Site design BMPs, such as tree wells, installed within a new development or redevelopment project are components of an overall storm water management strategy for the project. The presence of site design BMPs within a project is usually a factor in the determination of the amount of runoff to be managed with structural BMPs (i.e., the amount of runoff expected to reach downstream retention or biofiltration basins that process storm water runoff from the project as a whole). When site design BMPs are not maintained or are removed, this can lead to clogging or failure of downstream structural BMPs due to greater delivery of runoff and pollutants than intended for the structural BMP. Therefore, the City Engineer may require confirmation of maintenance of site design BMPs as part of their structural BMP maintenance documentation requirements. Site design BMPs that have been installed as part of the project should not be removed, nor should they be bypassed by re-routing roof drains or re -grading surfaces within the project. If changes are necessary, consult the City Engineer to determine requirements. 08/11/2026
EP H2 58i o

SD -A Tree Well
9Z0Z/ I. 1. /20
912 4° £89
Summary of Standard Inspecti on and Mai ntenance
The property owner is responsible to ensure inspection, operation and maintenance of permanent BMPs on their property unless responsibility has been f ormally transferred to an agency, community facilities district, home owners association, property owners association, or other special district.

Maintenance frequencies listed in this table are average/typical frequencies. Actual maintenance needs are site -specific, and maintenance may be required mo re frequently. Maintenance must be performed whenever needed, based on maintenance indicators presented in this table.

The BMP owner is responsible f or conducting reg ular inspections to see when maintenance is needed based on the maintenance indicators.

During the first year of operation of a structural BMP, inspecti on is rec ommended at least once pri or to August 31 and then m onthly fr om September thro ugh May. Inspection during a st orm event is also recommended . After the initial period of frequent insp ections, the minimum inspectio n and maintenance frequency can be determined based on the results of the first year inspections .

T hreshold/Indica tor
Maintenance Acti on
Typical M aintenance Frequency
Tree health
Routine actions as necessary to maintain
tree health.
• Inspect monthly.
• Maintain when needed .

Dead or diseased tree
Remove dead or diseased tree. Replace per
original plans.
• Inspect monthly.
• Maintain when needed .

Standing water in tree well for lo nger than
24 hours following a storm event
Surface ponding lo nger than appro ximately
24 hours follo wing a storm event may be
detrimental to tree health
Loo sen or replace s oils surr ounding the
tree to restore drainage.
• Inspect monthly and after every 0 .5 -inch
or larger st orm event. If standing water is
observed, increase inspecti on frequency
to after every 0.1 -inch or larger storm
event .
• Maintain when needed.

Presence of mosquito s/larvae
For images of egg rafts, larva, pupa, and
adult mosqu itos, see
http: // www.mosc uito. org/ biology
Disperse any standing water from the tree
well to nearby landscaping. Loosen or
replace so ils surro unding the tree to restore
drainage (and prevent sta nding water).
• Inspect m onthly and after every 0.5 -inch
or larger storm event. If mosquit os are
obser ved, increase inspection frequency
to after every 0 .1 -inch or larger storm
event.
• Maintain when needed
E-10
Jan . 2024

SD -A Tre e Well
9Z0Z/ I. 1. /80
918 40 1789
r - s f 4 . c . t. r
. int n . nc ct . n
. c , ° . nten . nc . , ncy
Entrance / opening to the tree well is
blo cked such that storm water will not drain
into the tree well (e.g., a curb inlet opening
is blocked by debris or a grate is clogged
causing runoff to flow arou nd instead of
into the tree well; or a surface depressi on is
filled such that runoff drains away from the
tree well)
M ake repairs as appropriate to restore
drainage into the tree well.
• Inspect monthly.
• Maintain when needed .

E-11 Jan . 2024

ATTACHMENT 2 - HYDROMODIFICATION MANAGEMENT CONTROLS:

SUPPORT DOCUMENTATION & CHECKLIST
❑ Check this box if this attachment is empty because the project is exempt from PDP hydromodification management requirements.

Each of the attachments indicated below should be considered for inclusion with the SWQMP. Use this checklist to indicate which attachments are included behind this coversheet.

Attachment
Sequence
Contents
Checklist
Attachment 2A
Hydromodification
Management Exhibit
X Included
See Hydromodification Management Exhibit
Checklist on the back of this Attachment cover
sheet.

Attachment 2B
Management of Critical Coarse
Sediment Yield Areas
See Section 6.2 of the BMP
Design Manual.

X Exhibit showing project drainage boundaries
marked on WMAA Critical Coarse Sediment Yield
Area Map
Analyses, as applicable, for Critical Coarse Sediment
Yield Area Determination, per BMP Design Manual:
❑ 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 Channels
See Section 6.3.4 of the BMP
Design Manual.

X Not performed
❑ Included
❑ Submitted as separate stand-alone document
Attachment 2D
Flow Control Facility Design,
including Structural BMP
Drawdown Calculations and
Overflow Design Summary
See Chapter 6 and Appendix G
of the BMP Design Manual
❑ Included
❑ Submitted as separate stand-alone document
Attachment 2E
Vector Control Plan
❑ Included
X Not required because BMPs will drain in less
than 96 hours

Page 33 of 38 ends

08/11/2026
PH2
585 of 876

ATTACHMENT 2A - HYDROMODIFICATION MANAGEMENT EXHIBIT
For Attachment 2A, provide map(s) for the project site, titled "Hydromodification Management Exhibit." The checklist below identifies minimum elements that must be included with the exhibit.

O Underlying hydrologic soil group
O Approximate depth to groundwater
▪ Existing natural hydrologic features (watercourses, seeps, springs, wetlands, etc.) O Critical coarse sediment yield areas to be protected
O Existing topography and impervious areas
O Existing and proposed site drainage network and storm drain structures O Proposed connections to offsite drainage
O Proposed demolition
O Proposed grading
O Proposed impervious features
O Proposed design features and surface treatments used to minimize imperviousness O Points of Compliance for hydromodification management O Existing and proposed drainage boundary and drainage area to each Point of Compliance (when necessary, create separate exhibits for pre -development and post -project conditions) O Structural BMPs for hydromodification management (location, type, and size) 08/11/2026

Page 34 of 38 ends

PH2
586 of 876

ATTACHMENT 2A
08/11/2026
PH2 587 of 876

9Z0Z/I I. /80
9L8 ; 0 889
I
)N ROSIER DRIVE
i
TNEPOS000NoRI0NtW COMMON IS

SELECTED TO
lAWS c0NSETOVAI1Vel}
PCC-1 '
LEGEND
> 9'

DMA BOUNDARY

SOIL TYPE

GROUNDWATER TABLE

FLOW DIRECTION

LOMA ALTA CREEK AND BUENA VISTA CREEK ARE EXISTING NATURAL

HYDROLOGIC FEATURES (WATERCOURSES , SEEPS, SPRINGS, WETLANDS) No CRITICAL COARSE SEDIMENT YIELD AREAS TO BE PROTECTED

MULTI STORY STRUCTURES MINIMIZE IMPERVIOUS AREA
-POC-1 BUENA VISTA CREEK (BASINS 2-5)
BASINS (2-5) CONFLUENCE DOWSTREAM OF THE

SITE AT MYNAH PL AND MARABOU LN
-POC-2 LOMA ALTA CREEK (BASIN -6)
-BASIN-1 DRAINS INTO GUAJOME LAKE THAT WILL BE
ROUTED TO POC-1 IN POST CONDITION
N
20 10 0 20 40 RU

SCALE IN FEET

GRAPHIC SCALE

NCNWTY MAP

PRE HMP MAP
FOR
W AX WING DRIVE 15 -L OTS

VISTA, CA
SWS ENGINEE RING, INC.
431 take be Manioc odm, bileno
.. 16
Sal 41 .44alarm CA
A .I 1,166 ,141-01114

LEGEND
OD
N
N
IMP -5 (BF -1)
BOTTOM A = 141 SF
DMA'
(SELFM ITIGATIN(}1
- - 1,427 SIF
H
IMP -6 (BF -1)
BO TTO M A = 1.406 SF
AQ UASAVE STOR. GE
1E . ma
P0 C-2 -'
91240 685
I MP -2 (SD -I) -
TREEWELL: 5 .5 ' 01 x 29' L
I MP -1 (BF1)r
DMA -2.311,341 SF: BOTTOM A= 121 SF
NEW TIDEWALK ^ .� mom
DMA -22 (SWAP)
1950 SF
5 F.F. 457.39
I F.F. 460.35
04,,1 - PC
-J IIP I, 27B
F. F. 463. 48
DMA -31 SIA/ AP),
.4,101 SF `_
IE . 156.16'
IMP -3 (BF -1)
BOTTOM A = 218 SF
(111 5 P05
4612 FGf, all U' IMP-4(BF-1)
BOTTOM A=318 SF
11,505 F
(4051 95.

F. F. 461.01.
- DMA -4
(SELF MITI GATING)
3,889 SF
1 5" IF OPEN
'0 °
> 9'

DMA BOUNDARY

SOIL TYPE

GROUNDWATER TABLE

FLOW DIRECTION

LANDSCAPE AREA

BIOFILTRATION AREA

IMPERVIOUS AREA (BLDG)

IMPERVIOUS AREA (CONCRETE)

IMPERVIOUS AREA (AC)

AREA THAT CAN NOT BE TREATED ONSITE (SWAP AREA)

STREET UNDISTURBED AREA (SWAP AREA)
TABULAR SUMMARY OF DMAs
DMA
IMP #
AREA
(SF)

IMPERVIOUS

AREA (SF)
S IMP
HSG
AREA WEIGHTED* *
RUNOFF

COEFFICIENT

VOLUME (DCV)

TREATMENT
SYSTEM
1 1
6,099
1,290

21.1 D

0.43 144

BIOFILTRATION
*2 .1
2 4,101
830

20.2 0

0.42 163
DMAs(2 .2+2.3)

TREEWELLS
*2.2
1,950 .
1,950
100
D

0.90 *2.3
1341
1341
100
D

0.90 3
3 4 .924

2.812

57.1 D
064
173

BIOFILTRATION
4 -
3,889

0.00 0.0
D
0 .30
-

SELF -MITIGATING
5 4
11,505
9,661

84.0 D

0.80 506

BIOFILTRATION
6 5
7,187
2,561
35 .6
D
0 .51
202

BIOFILTRATION
7 6
33 .809
23,665
70 .0
D
0 .72
1,339

BIOFILTRATION/

AQUASAVE
8 -
1,427
0 0 .0
D
0 .30
-

HYDROLOGIC FEATURES (WATERCOURSES, SEEPS, SPRINGS, WETLANDS)

NO CRITICAL COARSE SEDIMENT YIELD AREAS TO BE PROTECTED

MULTI STORY STRUCTURES MINIMIZE IMPERVIOUS AREA
— **PER PERVIOUS C COEFFICIENT = 0.3 & IMPERVIOUS C COEFFICIENT = 0.9 — POC-1: (DMAs 1-3) DRAIN INTO BUENA VISTA CREEK
DMA -4 ALSO DRAINS INTO BUENA VISTA CREEK
DMAs (1-4) CONFLUENCE DOWNSTREAM OF THE SITE AT

MYNAH PL AND MARABOU LN
— ROC-2: (DMAs 5-7) DRAIN INTO LOMA ALTA CREEK
DMA -8 ALSO DRAINS INTO LOMA ALSO CREEK
N
20 10 0 20 40

SCALE IN FEET

GRAPHIC SCALE
POST HMP MAP 1 OF 2
FOR
WAX WING DRIVE 15 -LOTS

VISTA, CA
WSWS E NGI NEERING, IN C.

O BIOFILTRATION CHART (BF -1)
DSN.4
IMP k

ORIFICE

DIAMETER
(IN)

ORIFICE INVERT

ELEVATION
(�
OUTLET
PIPE
(IN)
# OF
RISERS

GRATE SIZE IN

FEET (N,Y)

BASIN TOTAL
SURFACE *

DEPTH (IN)

BASIN REQUIRED

TREATMENT AREA
(SF)
BASIN

BOTTOM AREA
(SF)

BASIN PROVIDED

TREATMENT AREA
(SF)

PERFORATED

PIPE DIAMETER
(IN)
MULCH
DEPTH
"A " (IN)

AMENDED

SOIL DEPTH
"B" (IN)

ALTER COURSE
DEPTH
"C1&C2" (IN)**

STORAGE
"0" (IN)***

BOTTOM BASIN

ELEVATION
(FT)

DISTANCE FROM

BOTTOM OF POND

TO TOP OF GRATE

TOP OF GRATE
ELEVATION+ +
(FT)
DCV
(OF)
VOLUME
PROVIDED**.
(CF)
AMP

ELEVATION
(FT)
100YR

ELEVATION
(FT)

EFFECTIVE

ELEVATION
( H)

TOP OF BERM

ELEVATION
(FT)

PRODDED

FREE BOARD
(IN)

0.83'
461.33'
173
580
461 .33
461.53
461.58
462.25

8.04 2:1
4 0. 26
455.50'
10 1
1' X 1'
21"
280
318
318
6"
3"
18 "
6"
12"
458 .50'

0.83'
459.33'
506
1,097
459.33'
459.60'
459.53'
460.25'

7.80 "
2:1
®
5 0.25
451.00'
10 1
1' X 1'
21"
110
141
141
6"
3"
18"
6"
12 "
455 .50'

0.83'
456.33'
202
396
456.33'
456.63'
456.69'
457.25'
6 .72"
2:1
erv
6 03
12 1
1' X 1'
21 "
731
1400
1400
-
3"
18"
3"
33"
455.00'

0.83'
455:83'
1,339
6,095
455.83'
456.04'
455,86'
456.75'

8.52"
2:1
456.25'
* FROM TOP OF MULCH TO TOP OF BERM
100-YR STORAGE DEPTH

MULCH (A)

M EDIA (B)
WIIA A MIN 5" IN/HR

MLDIA SPECIFICATION
,NASH SAND (C-1)
2 N
100-YR POND DEPTH

BASIN BOTTOM
4,-YR STORAGE-AOUASAVE
(0).

RAMP- DEPTH
** 3" ASTM 33 (TOP) , 3" ASTM NO 8 (BOTTOM)

BASIN TOP
II
II 1TIIrI�IIIII III
ORIFICE -1

TREATMENT BOTTOM
AREA

FOR LETTERS (A RD D) PLEASE
SEE BIOFILTRATION CHART (BF -1)
BIOFILTRATION FACILITY DETA9_ (IMP -6)

RISER OUTLET STRUCTURE

F REE BOA RD

SURFACE TOTAL DEPTH

VEGETATON PER
LANDSCAPING PLAN .

HMP STORAGE
DEPTH

EXISTING GROUND
IMPERVIOUS LINER 3D M IL PVC OR EQUIV.
'.KITS CONTRACTOR TO SUBMIT PRODUCT DATA

TO ENGINEER OF RECORD FOR APP ROVAL
PRIOR TO CONSTRUCTION.

OUTLET PIPE

RESTRICTOR PLATE
(SEE BELOW)

APPROVED CORROSION RESISTANT CONCRETE
ANCHORS (4X) WITH PLATE WASHERS
P •F PIP HI
SE

ONTINUO S BEAD OF SEALANT

ROUND RESTRICTO R PLATE PERIM ETER
LL
AD `L TO CONCRETE WITH APPROVED
AD B: )E (LOCTITE EPDXY -HEAVY DUTY) AND

VE CO NCRETE WEDGE ANCHOR BO LTS
(A' k AS -125 (1/2" DIA. 5, DEPTH)
-E CV C - OR PLATE ELEVATION
-h FLOW -CONTROL ORIFICE
OO

ORIFICE (SEE BELOW )

RESTRIC TOR PLATE
ply,. p•• aN B• "IN

PER DETAIL AND CHA

ARUSAVE STORAGE PER

BIOFILTRATION DETAIL

AOUASAVE STORAGE

IMPERMEABLE L NER PER
R ISER .OTTOM BIOFILTRATION DETAIL
O7 BIOFILTRAT1cN PLATE & ORIFICE DETAIL (IMP -6)
***(GRAVEL, ASTM 57) FOR IMPS (1,3,4,5), ++PER HMP
AQUASAVE FOR IMP -6
100—YR STORAGE DEPTH

MULCH (A)

MEDIA (H)
WITH A MIN 5" IN/HR

PER MEDIA SPECIFIC ATI ON
FILTER WA SH SAND (C-1)
FILTER PEA GRAVEL (02)
GRAVEL SAND (0
3/4 IN CRUSH HOER
A" PERFORATED_,EIPF
(3' FROM THE BOTTOM)

BASIN TOP
100—YR POND DEP
LII�I

ORIFI CE
*** * INCLUDES: 12 " SURFACE 100% VOID
SOIL GRAVEL 40% VOID
90% VOID FOR AQUASAVE STORAGE (IMP -6)

RISER OUTLET STRUCTURE

TREATMENT BOTTOM
AREA
FOR LETTERS (A TO D).. PLEASE
SEE BIOFILTRATION CHART (BF -1)
BIOFILTRATION FACILITY DETAIL (IMPS 1.3.4,5)

RESTRICTOR PLATE
(SEE BELOW)

APPROV ED CORROSION RESISTANT CON CRETE
ANCHORS (4X) WITH PLATE WASHERS

PERF PIPE BEHIND

RISER WALL
TIN *. A* •F A NT

AROUND AROUND RESTRICTOR PLATE

ADHERED TO CONCRETE WITH APPROVED
ADHESIVE (LOCTITE EPDXY —HEAVY DUTY) AND

VESTIL CONCRET E WEDGE ANCHOR BOLTS
(M ODLE HAS -125 (1/2" DIA, 5" DEPTH)

SEE RESTRICTOR PLATE ELEVATION

ORIFICE (SEE BELOW )
REM-R .70R rw

BIOFILTRATION BASIN

PER DETAIL AND CHARFJ

GRAVEL PER

BIOFILTRATION DETAIL

GRAVEL STORAGE
FLOW —CONTROL ORIFICE �1L L ►'±� SM M! 3" GRAVEL BASE

IMPERMEABLE LINER PER

BIOFILTRA TON DETAIL
BIOFILTRATION PLATE & ORIFICE DETAIL (IMPs
NIS

FREE BOARD

SURFACE TOTAL DEPTH

VEGETATION PER

LANDSCAPING PLAN

HMP STORAGE
DEPTH

EXISTING GROUND
IMPERVIOUS CNER 30 MIL PVC OR EQUIV.

CONTRACTOR TO SUBMIT PRODUCT DATA

TO ENGINEER OF RECORD FOR APPROVAL
PRIOR TO CONSTRUCTION.

OUTLET PIPE
AQUASAVE (IMP -6)

SHE C OUNTY OF SAN DIEGO

LOW IMPACT TERM,O NN PLACE IINFILLTCRARON BAR NOIX OFAND 5 INCHES
PER HOUR. BSM SHALL RE COMPOSED OF THE FOLLOWING:

SANDY LOAM

LOMFOSSTON
RAND

COMPOST

SAND SILT CLAY
VOLUME
BD -50B
0-20%
20%
WEIGHT
T5-BOR IIOR MAXI=S MAX
9S MAXI
' fl% COMPOST BY W BCH RESULTS M APPROAMATELY
5% ORGANIC MATTER BY WONT .

NUTRIENT -SENSITIVE GSM MIX PER . FACTSHEET BF -2
TREE -WELL (I MP -2)
POST HMP MAP 2 OF 2
FOR
WAX WING DRIVE 15 -LOTS

VISTA, CA
SWS E NGI NEE RING, I NC.

ATTACHMENT 2B
08/11/2026
PH2 591 of 876

's aw c a• O.,1
sai a S 3e iru slu6iak aso3ja�ry
4 1I I HX3 VASDD
592 of 876
N
2 0_
08/11/2026

SWMM ANALYSIS

FLOW DURATION CURVE ANALYSIS
1 08/11/2026
PH2 593 of 876

ATTACHMENT 2D
08/11/2026
PH2 594 of 876

Appendix G: Guidance for Continuous Simulation and Hydromodification Management Sizing Factors
www.sandiegocounty.gov/stormwater
08/11/2026
G-35 Effective January 1, 2019
PH2 595 of 876

INTRODUCTION:

The approach used to model the proposed residential development project site in the city of Vista using the Environmental Agency (EPA) Storm Water Management Model 5.1 (SWMM). SWMM models were prepared for the pre and post -development conditions at the project site to determine if the proposed LID treatment basins have sufficient volume to meet Hydromodification Management Plan (HMP) requirements. The San Diego Regional Water Quality Control board (SDRWQCB) established these requirements in the final HMP , dated March 2011, prepared for the County of San Diego by Brown and Caldwell, as modified by the HMP dated February 2016 per City of Vista BMP Design Manual.

SWMM MODEL DEVELOPMENT
The proposed project site consists of 15 townhomes (two-story structure) with associated driveway, private street, utilities, and other associated improvements and treatment basins within the City of Vista, California. The total developed area is 1.67 ac. SWMM models were prepared for this study, one for pre - development and one for post -development conditions.

There are two POCs on site (selected per post condition), POC-1 located on the northeast for DMAs (1- 4), POC-2 located on the southwest corner of the site where DMAs 5-7 will discharge into from multiple biofiltration basins into existing storm drain systems. DMA 4 and 8 are self -mitigating areas sheet flow offsite as they do in the existing condition.

The project site in existing condition drains into three watershed bodies. Small area (basin -1, 0.034 ac) of the existing condition, west of high point on W Babier Drive will drain toward Guajome Lake and then into lower San Luis Rey River and basins 2 and 3 drain into Buena Vista Creek and basin -4 into loma Alta Creek. Basin 3 sheet flows easterly to offsite (not concentrated).

In post condition, the runoff from basins 1-4 will drain toward Buena Vista Creek which will eliminate the small area that was draining to Guajome in existing condition to be routed toward Buena Vista Creek as well.

For both SWMM models, flow duration curves were prepared for POCs 1-2 to determine if the proposed HMP facility is sufficient to meet the current HMP requirements. Table 1.0 summarizes the contributing area for POC 1-2 in pre and post -development conditions.

TABLE 1.0
POC
Pre-Dev Area (ac
Post-Dev Area ac)
1 0.43 (basins 2-5) *

0.43 (basins 1-4
2 0.99 (basin -6)

1.24 (basins 5-8
*HMP analysis for POC-1 would be challenging if we analyze and use the basins that discharge north and easterly of the site into multiple locations. We know that all the basins (2-5) sheet flow offsite and concentrate in multiple points until they confluence at one point that is the downstream of the project site (Mynah PI and Marabou Ln) and finally discharge into an existing storm drain system located on Moa Dr (west of Marabou Ln) (prior to discharging into Buena Vista Creek. Only small portion of the site (0.034 ac) drains into West of the high point on Bobier Dr. and ultimately into Guajome Lake and then into San Luis Rey River, however, this small area in post condition, will be routed into Buena Vista Creek. Therefore, for the simplicity of the analysis at POC-1 which is also more conservative, we will assume the same pre 2 08/11/2026
PH2 596 of 876

HMP area (basins 2-5) to match the area (basins 1-4) in the post HMP analysis that drain into same watershed (Buena Vista Creek).

The inputs required to develop SWMM models include rainfall, watershed characteristics, and Integrated Management Practices (IMP) configurations. The Oceanside gauge from the Project Clean Water website was used for this study, since it is the most representative of the project site precipitation due to elevation and proximity of the project site.

Evaporation for the site was modeled using average monthly values from City of Vista BMP Design Manual Appendices, Table G.1-1. According to the NRCS WebSoil Survey, the site has a soils type "D".

HMP MODELING

PROPOSED CONDITION
POC-1
POC-1 is where all the treated and self -mitigating runoff from DMAs 1-4 discharge into west of W Bobier Drive and adjacent properties and then discharge into Buena Vista Creek and ultimately to the Pacific Ocean.

POC-2 is where all the treated runoff from DMAs 5-8 will discharge southwest corner offsite and then into Loma Alta Creek and ultimately to Pacific Ocean.

The biofiltration basins (IMPS 1, 3, 4, 5 ,6) are responsible for handling hydromodification requirements for POC-1 and 2. The biofiltration basins have been designed with a uniform surface depth of 10 -inch for IMPs (1, 3, 4, 5, 6) with each basin total depth to be 21 -inch for HMP and 100yr required freeboard.

Each IMP is comprised of a 3 -inch mulch layer, 18 -inch layer of amended soil (a highly sandy, organic rich compost with an infiltration rate of 5 in/hr), 6 -inch of filter course and 12 inch gravel layer for IMPs (1, 3, 4, 5). IMP -6 is comprised of a 3 -inch mulch layer, 18 -inch layer of amended soil (a highly sandy, organic rich compost with an infiltration rate of 5 in/hr), 3 -inch of filter course and 33 inch storage layer (AcuaSave) for additional detention (see underground layers depth below'). Below the gravel/AquaSave layer, each basin is lined to prevent infiltration into the underlying soil. Flow will discharge from basins (IMPs 1, 3, 4) via a low flow orifice outlet set at the bottom, 3 inch from bottom of the gravel. There are two orifices proposed for the IMP -6, 0.8 inch at the bottom of storage (AqauSave) and 3 inch orifice set 60 inch from the bottom of the storage. A riser structures will be constructed in each basin that peak flows can be safely discharged to the receiving storm drain systems. The area and depth used in SWIM/ model is deferent than what is shown on the "Biofiltration Value Table" because of limitation of SWMM software (volume used in SWMM model is equivalent to what will be constructed). 3 08/11/2026
PH2 597 of 876

TABLE 1.1- Summary of Existing Condition for POC-1 and POC-2 DMA
Tributary Area, A(ac)
Impervious Percentage, IP
POC-1: Basins 2-5

0.43 0%
POC-2: Basin 6

0.99 0%
ABLE 1.2- Summary of Developed Condition for POC-1
DMA
Biofiltration #
Tributary Area, A(ac)
Impervious Percentage, IP
DMA -1
IMP -1

0.14 21.6%
DMA -2
-

0.09 20.2%
DMA -3
IMP -3

0.11 59.8%
DMA -4
Self -Mitigating

0.089

0.0 TABLE 1.3- Summary of Developed Condition for POC-2 DMA
Biofiltration #
Tributary Area, A(ac)
Impervious Percentage, IP
DMA -5
IMP -4

0.26 86.4%
DMA -6
IMP -5

0.17 36.3%
DMA -7
IMP -6

0.78 73.0%
DMA -8
Self -Mitigating

0.03 0.0
Effective Depth
IMPs
Depth (ft)
IMP -1

1.17 IMP -3

1.08 IMP -4

1.03 IMP -5

1.19 IMP -6

0.86 The biofiltration basins were modeled using the biofiltration LID module within SWMM. The biofiltration module can model the underground gravel, underdrain with an orifice plate, amended soil layer, and a surface pond up to the elevation of the invert of the spillway.

It should be noted that detailed outlet location and elevations will be shown on the construction plans based on the recommendations of this study.

Underground layers depth
For (IMPs 1,3,4,5):
3" Mulch
18" Soil
6" Filter Course
12" gravel
For (IMP -6):
3" Mulch
18" Soil
3" Filter Course
33" AquaSave Storage
4 08/11/2026
PH2 598 of 876

BMP MODELING FOR HMP PURPOSES
* The Green Ampt data's for Soil D are selected for this site.

FLOW DURATION CURVE COMPARISON
The flow Duration Curve (FDC) were compared at the project's POCs by exporting the hourly runoff time result from the SWMM to a spreadsheet. For each POC, the FDC was compared between 10% of the existing condition Q2 up to the existing condition Qio. Q2 and Qio were determined by the statistics analysis report exported to spreadsheet from the SWMM model, which is based on the Weibull Plotting Positions. The runoff time series was also exported from the SVC/MM model to a spreadsheet to calculate flow durations.

The range between 10% of Q2 and Q10 was divided into 100 equal time intervals; the number of hours that each flow rate was exceeded was counted from the hourly series. Additionally, the intermediate peaks with a return period "i" were obtained (Qi with i=3 to 9). For the purpose of the plot, the values were presented as percentage of time exceeded for each flow rate. FDC comparison for each POC is illustrated in the following Figure -1.

As can be seen in Figures 1, the FDCs for the proposed condition with the HMP facilities are within 110% of the curve for the existing condition in both peak flow and duration. The additional runoff volume generated from developing the site will be released to the storm drain system at a flow rate below the 10% Q2 lower threshold. Additionally, the project will not increase peak flow rates between the Q2 and the Q10.
5 08/11/2026
PH2 599 of 876

DRAWDOWN TIME
To ensure compliance with the 96 hour toral drawdown requirements and 24 hour surface ponding drawdown requirement per current City of Vista BMP Design Manual Appendicies, drawdown calculation are provided below in this report. Please see the calculations (Elevation Discharge and Drawdown Summary).

Orifice Area: ((D/12/2)^2)*i
2 Orifice flow Rate (Q): Ca
8244
HD is the elevation of the centroid of the orifice in inches (assumed equal to the invert of the orifice for small orifices and in our design equal to 0)
H is the depth of the water in inches.

Drawdown Time (hr): (V/Q)/3600
Where:

D is Orifice diameter (in)
Cg is Orifice discharge coefficient = 0.61
A is Orifice area (sf)
V is DCV volume (cf)
g = 32.2 ft/s^2
C = Cg (605/A.m) (tD^2/8) J(g/6) , per Section G.1.5.3.4 of Appendix G of the County of San Diego BMP Design Manual
DMA 1
DMA
Cg

0.61 0.61

DIAMETER

0.250

0.250
AREA
121
218
C*

0.1734

0.0963
DMA 5
DMA -6
DMA -7
Cg

0.61 0.61

0.61 DIAMETER

0.260

0.250

0.800
AREA
318
141
1400
C*

0.0714

0.1499

0.1535

SUMMARY
This study has demonstrated that the proposed biofiltration basins with gravel storage layer provided within the Vista project are sufficient to meet the current HMP criteria and the respective orifice and outlet structure, are incorporated as specified within the proposed project site.

KEY ASSUMPTIONS

1. The biofiltration basins are lined in order to prevent infiltration into the underlying soil. 6 08/11/2026
PH2 600 of 876

Drawdown Calculation Summary
Vista Waxwing Drive
Biofiltration
IMP -1
IMP -3
IMP -4
IMP -5
IMP -6
Surface
Average Discharge Rate
cfs

0.0032

0.032

0.0035

0.0032

0.1346
Ponding Depth
in
10 10
10 10
10 Bottom Area
sf
121
218
318
141
1400
Top Area
sf
308
465
601
371
2045
Drawdown Time
hr

15.5 2.5

30.4 18.5

3.0 Soil Layer
Average Discharge Rate
cfs

0.0025

0.0027

0.0025

0.0324
Thickness
in
24 24
24 24
24 Area
sf
121
218
318
141
1400
Porosity

0.4 0.4

0.4 Field Capacity

0.2 0.2

0.2 Drawdown Time
hr

5.4 9.7

13.1 6.3

4.8 Gravel/AquaSave Layer
Average Discharge Rate
cfs

0.0013

0.0014

0.0013

0.0198
Thickness
in
15 15
15 15
33 Area
sf
121
218
318
141
1400
Porosity

0.4 0.4

0.4 Drawdown Time
hr

12.9 23.3

31.5 15.1

21.6 TOTAL DRAWDOWN TIME
hr

33.8 35.4

75.0 39.8

29.4 08/11/2026
PH2 601 of 876

ELEVATION -DISCHARGE CALCULATOR

DISCHARGETHRU UNDERDRAIN ORIFICE
WEIR FLOW (1-'D-1' inches)
ORIFICE FLOW ('D' inches and over) DMA -1 (IMP -1)
INPUT
Orifice Diameter, D = 0.2500 inches

CALCULATE
Weir Equation, Q= 3.0WHis
Orifice Equation, Q = 0.61A(2gH)os
ELEVATION (in) DISCHARGE (cfs)
Gravel = 15"
Soil = 24"
Surface pond =10"
Total surface depth = 21"
1 0.0005 Bottom of Storage
2 3
4 5
6 7
8 9
10 11
12 13
14 15 0.0019 Top of Storage
16 17
18 19
20 21
22 23
24 25
26 27
28 29
30 31
32 33
34 35
36 37
38 39 0.0030 Top of Mulch
40 41
42 43
44 45
46 47
48 49 0.0034 Surface Pond 10
50 51
52 53
54 55
56 57
58 59
60 61
62 63
64 65
66 67
68 69
70 71
72 73
74 75
76 77
78 0.0007

0.0008

0.0009

0.0011

0.0012

0.00131 _

0.0014

0.0015

0.0016

0.0017

0.0018
Ave Storage

0.0019

0.0020

0.0021

0.0022

0.0023

0.0024

0.0025

0.00251 _

0.0025

0.0026

0.0027

0.0028

0.0029

0.0030
Ave soil

0.0030

0.0031

0.0032

0.00321

0.0032

0.0033

0.0033
Ave Surface

0.0034

0.0035

0.0036

0.0037

0.0038

0.0039

0.0040

0.0041

0.0042

0.0043

EFFECTIVE HEIGHT ORIFICE AREA WEIR LENGTH
H (in) (sq ft) (ft)

0.875 0.0003 0.00
L875 0.0003 0.00

2.875 0.0003 0.00

3.875 0.0003 0.00

4.875 0.0003 0.00

5.875 0.0003 0.00

6.875 0.0003 0.00

7.875 0.0003 0.00

8.875 0.0003 0.00

9.875 0.0003 0.00

10.875 0.0003 0.00

11.875 0.0003 0.00

12.875 0.0003 0.00

13.875 0.0003 0.00

14.875 0.0003 0.00

15.875 0.0003 0.00

16.875 0.0003 0.00

17.875 0.0003 0.00

18.875 0.0003 0.00

19.875 0.0003 0.00

20.875 0.0003 0.00

21.875 0.0003 0.00

22.875 0.0003 0.00

23.875 0.0003 0.00

24.875 0.0003 0.00

25.875 0.0003 0.00

26.875 0.0003 0.00

27.875 0.0003 0.00

28.875 0.0003 0.00

29.875 0.0003 0.00

30.875 0.0003 0.00

31.875 0.0003 0.00

32.875 0.0003 0.00

33.875 0.0003 0.00

34.875 0.0003 0.00

35.875 0.0003 0.00

36.875 0.0003 0.00

37.875 0.0003 0.00

38.875 0.0003 0.00

39.875 0.0003 0.00

40.875 0.0003 0.00

41.875 0.0003 0.00

42.875 0.0003 0.00

43.875 0.0003 0.00

44.875 0.0003 0.00

45.875 0.0003 0.00

46.875 0.0003 0.00

47.875 0.0003 0.00

48.875 0.0003 0.00

49.875 0.0003 0.00

50.875 0.0003 0.00

51.875 0.0003 0.00

52.875 0.0003 0.00

53.875 0.0003 0.00

54.875 0.0003 0.00

55.875 0.0003 0.00

56.875 0.0003 0.00

57.875 0.0003 0.00

58.875 0.0003 0.00

59.875 0.0003 0.00

60.875 0.0003 0.00

61.875 0.0003 0.00

62.875 0.0003 0.00

63.875 0.0003 0.00

64.875 0.0003 0.00

65.875 0.0003 0.00

66.875 0.0003 0.00

67.875 0.0003 0.00

68.875 0.0003 0.00

69.875 0.0003 0.00

70.875 0.0003 0.00

71.875 0.0003 0.00

72.875 0.0003 0.00

73.875 0.0003 0.00

74.875 0.0003 0.00

75.875 0.0003 0.00

76.875 0.0003 0.00

77.875 0.0003 0.00
08/11/2026
PH2
602 of 876

ELEVATION -DISCHARGE CALCULATOR

DISCHARGETHRU UNDERDRAIN ORIFICE
WEIR FLOW (1'D-1' inches)
ORIFICE FLOW ('D' inches and over) DMA -3 (IMP -3)
INPUT
Orifice Diameter, D = 0.2500 inches

CALCULATE
Weir Equation, Q= 3.0WHis
Orifice Equation, Q = 0.61A(2gH)os
ELEVATION (in) DISCHARGE (cfs)
Gravel = 15"
Soil = 24"
Surface pond =10"
Total surface depth = 21"
1 0.0005 Bottom of Storage
2 3
4 5
6 7
8 9
10 11
12 13
14 15 0.0019 Top of Storage
16 17
18 19
20 21
22 23
24 25
26 27
28 29
30 31
32 33
34 35
36 37
38 39 0.0030 Top of Mulch
40 41
42 43
44 45
46 47
48 49 0.0034 Surface Pond 10"
50 51
52 53
54 55
56 57
58 59
60 61
62 63
64 65
66 67
68 69
70 71
72 73
74 75
76 77
78 0.0007

0.0008

0.0009

0.0011

0.0012

0.00131 _

0.0014

0.0015

0.0016

0.0017

0.0018
Ave Storage

0.0019

0.0020

0.0021

0.0022

0.0023

0.0024

0.0025

0.00251 _

0.0025

0.0026

0.0027

0.0028

0.0029

0.0030
Ave soil

0.0030

0.0031

0.0032

0.00321

0.0032

0.0033

0.0033
Ave Surface

0.0034

0.0035

0.0036

0.0037

0.0038

0.0039

0.0040

0.0041

0.0042

0.0043

EFFECTIVE HEIGHT ORIFICE AREA WEIR LENGTH
H (in) (sq ft) (ft)

0.875 0.0003 0.00
L875 0.0003 0.00

2.875 0.0003 0.00

3.875 0.0003 0.00

4.875 0.0003 0.00

5.875 0.0003 0.00

6.875 0.0003 0.00

7.875 0.0003 0.00

8.875 0.0003 0.00

9.875 0.0003 0.00

10.875 0.0003 0.00

11.875 0.0003 0.00

12.875 0.0003 0.00

13.875 0.0003 0.00

14.875 0.0003 0.00

15.875 0.0003 0.00

16.875 0.0003 0.00

17.875 0.0003 0.00

18.875 0.0003 0.00

19.875 0.0003 0.00

20.875 0.0003 0.00

21.875 0.0003 0.00

22.875 0.0003 0.00

23.875 0.0003 0.00

24.875 0.0003 0.00

25.875 0.0003 0.00

26.875 0.0003 0.00

27.875 0.0003 0.00

28.875 0.0003 0.00

29.875 0.0003 0.00

30.875 0.0003 0.00

31.875 0.0003 0.00

32.875 0.0003 0.00

33.875 0.0003 0.00

34.875 0.0003 0.00

35.875 0.0003 0.00

36.875 0.0003 0.00

37.875 0.0003 0.00

38.875 0.0003 0.00

39.875 0.0003 0.00

40.875 0.0003 0.00

41.875 0.0003 0.00

42.875 0.0003 0.00

43.875 0.0003 0.00

44.875 0.0003 0.00

45.875 0.0003 0.00

46.875 0.0003 0.00

47.875 0.0003 0.00

48.875 0.0003 0.00

49.875 0.0003 0.00

50.875 0.0003 0.00

51.875 0.0003 0.00

52.875 0.0003 0.00

53.875 0.0003 0.00

54.875 0.0003 0.00

55.875 0.0003 0.00

56.875 0.0003 0.00

57.875 0.0003 0.00

58.875 0.0003 0.00

59.875 0.0003 0.00

60.875 0.0003 0.00

61.875 0.0003 0.00

62.875 0.0003 0.00

63.875 0.0003 0.00

64.875 0.0003 0.00

65.875 0.0003 0.00

66.875 0.0003 0.00

67.875 0.0003 0.00

68.875 0.0003 0.00

69.875 0.0003 0.00

70.875 0.0003 0.00

71.875 0.0003 0.00

72.875 0.0003 0.00

73.875 0.0003 0.00

74.875 0.0003 0.00

75.875 0.0003 0.00

76.875 0.0003 0.00

77.875 0.0003 0.00
08/11/2026
PH2 603 of 876

ELEVATION -DISCHARGE CALCULATOR

DISCHARGETHRU UNDERDRAIN ORIFICE
WEIR FLOW (1'D-1' inches)
ORIFICE FLOW ('D' inches and over) DMA -5 (IMP -4)
INPUT
Orifice Diameter, D = 0.2600 inches

CALCULATE
Weir Equation, Q= 3.0WHis
Orifice Equation, Q = 0.61A(2gH)os
ELEVATION (in) DISCHARGE (cfs)
Gravel = 15"
Soil = 24"
Surface pond =10"
Total surface depth = 21"
1 0.0005 Bottom of Storage
2 3
4 5
6 7
8 9
10 11
12 13
14 15 0.0020 Top of Storage
16 17
18 19
20 21
22 23
24 25
26 27
28 29
30 31
32 33
34 35
36 37
38 39 0.0032 Top of Mulch
40 41
42 43
44 45
46 47
48 49 0.0036 Surface Pond 10"
50 51
52 53
54 55
56 57
58 59
60 61
62 63
64 65
66 67
68 69
70 71
72 73
74 75
76 77
78 0.0007

0.0009

0.0010

0.0011

0.0013

0.00141 _

0.0015

0.0016

0.0017

0.0018

0.0019

0.0019
Ave Storage

0.0021

0.0022

0.0023

0.0024

0.0025

0.0026

0.0027

0.00271 _

0.0028

0.0029

0.0030

0.0031

0.0032

0.0032
Ave soil

0.0033

0.0034

0.00351

0.0035

0.0036

0.0036
Ave Surface

0.0037

0.0038

0.0039

0.0040

0.0041

0.0042

0.0043

0.0044

0.0045

0.0046

EFFECTIVE HEIGHT ORIFICE AREA WEIR LENGTH
H (in) (sq ft) (ft)

0.870 0.0004 0.00

1.870 0.0004 0.00

2.870 0.0004 0.00

3.87 0.0004 0.00

4.87 0.0004 0.00

5.87 0.0004 0.00

6.87 0.0004 0.00

7.87 0.0004 0.00

8.87 0.0004 0.00

9.87 0.0004 0.00

10.87 0.0004 0.00

11.87 0.0004 0.00

12.87 0.0004 0.00

13.87 0.0004 0.00

14.87 0.0004 0.00
1587 0.0004 0.00

16.87 0.0004 0.00

17.87 0.0004 0.00

18.87 0.0004 0.00

19.87 0.0004 0.00

20.87 0.0004 0.00

21.87 0.0004 0.00

22.87 0.0004 0.00

23.87 0.0004 0.00

24.87 0.0004 0.00

25.87 0.0004 0.00

26.87 0.0004 0.00

27.87 0.0004 0.00

28.87 0.0004 0.00

29.87 0.0004 0.00

30.87 0.0004 0.00

31.87 0.0004 0.00

32.87 0.0004 0.00

33.87 0.0004 0.00

34.87 0.0004 0.00

35.87 0.0004 0.00

36.87 0.0004 0.00

37.87 0.0004 0.00

38.87 0.0004 0.00

39.87 0.0004 0.00

40.87 0.0004 0.00

41.87 0.0004 0.00

42.87 0.0004 0.00

43.87 0.0004 0.00

44.87 0.0004 0.00

45.87 0.0004 0.00

46.87 0.0004 0.00

47.87 0.0004 0.00

48.87 0.0004 0.00

49.87 0.0004 0.00

50.87 0.0004 0.00

51.87 0.0004 0.00

52.87 0.0004 0.00

53.87 0.0004 0.00

54.87 0.0004 0.00

55.87 0.0004 0.00

56.87 0.0004 0.00

57.87 0.0004 0.00

58.87 0.0004 0.00

59.87 0.0004 0.00

60.87 0.0004 0.00

61.87 0.0004 0.00

62.87 0.0004 0.00

63.87 0.0004 0.00

64.87 0.0004 0.00

65.87 0.0004 0.00

66.87 0.0004 0.00

67.87 0.0004 0.00

68.87 0.0004 0.00

69.87 0.0004 0.00

70.87 0.0004 0.00

71.87 0.0004 0.00

72.87 0.0004 0.00

73.87 0.0004 0.00

74.87 0.0004 0.00

75.87 0.0004 0.00

76.87 0.0004 0.00

77.87 0.0004 0.00
08/11/2026
PH2
604 of 876

ELEVATION -DISCHARGE CALCULATOR

DISCHARGETHRU UNDERDRAIN ORIFICE
WEIR FLOW (1'D-1' inches)
ORIFICE FLOW ('D' inches and over) DMA -6 (IMP -5)
INPUT
Orifice Diameter, D = 0.2500 inches

CALCULATE
Weir Equation, Q= 3.0WHis
Orifice Equation, Q = 0.61A(2gH)os
ELEVATION (in) DISCHARGE (cfs)
Gravel = 33"
Soil = 24"
Surface pond =10"
Total surface depth = 21"
1 0.0005 Bottom of Storage
2 3
4 5
6 7
8 9
10 11
12 13
14 15 0.0019 Top of Storage
16 17
18 19
20 21
22 23
24 25
26 27
28 29
30 31
32 33
34 35
36 37
38 39 0.0030 Top of Mulch
40 41
42 43
44 45
46 47
48 49 0.0034 Surface Pond 10"
50 51
52 53
54 55
56 57
58 59
60 61
62 63
64 65
66 67
68 69
70 71
72 73
74 75
76 77
78 0.0007

0.0008

0.0009

0.0011

0.0012

0.00131 _

0.0014

0.0015

0.0016

0.0017

0.0018
Ave Storage

0.0019

0.0020

0.0021

0.0022

0.0023

0.0024

0.0025

0.0026

0.0027

0.0028

0.0029

0.0030
Ave soil

0.0030

0.0031

0.0032

0.0033

0.0033
Ave Surface

0.0034

0.0035

0.0036

0.0037

0.0038

0.0039

0.0040

0.0041

0.0042

0.0043

EFFECTIVE HEIGHT ORIFICE AREA WEIR LENGTH
H (in) (sq ft) (ft)

0.875 0.0003 0.00
L875 0.0003 0.00

2.875 0.0003 0.00

3.875 0.0003 0.00

4.875 0.0003 0.00

5.875 0.0003 0.00

6.875 0.0003 0.00

7.875 0.0003 0.00

8.875 0.0003 0.00

9.875 0.0003 0.00

10.875 0.0003 0.00

11.875 0.0003 0.00

12.875 0.0003 0.00

13.875 0.0003 0.00

14.875 0.0003 0.00

15.875 0.0003 0.00

16.875 0.0003 0.00

17.875 0.0003 0.00

18.875 0.0003 0.00

19.875 0.0003 0.00

20.875 0.0003 0.00

21.875 0.0003 0.00

22.875 0.0003 0.00

23.875 0.0003 0.00

24.875 0.0003 0.00

25.875 0.0003 0.00

26.875 0.0003 0.00

27.875 0.0003 0.00

28.875 0.0003 0.00

29.875 0.0003 0.00

30.875 0.0003 0.00

31.875 0.0003 0.00

32.875 0.0003 0.00

33.875 0.0003 0.00

34.875 0.0003 0.00

35.875 0.0003 0.00

36.875 0.0003 0.00

37.875 0.0003 0.00

38.875 0.0003 0.00

39.875 0.0003 0.00

40.875 0.0003 0.00

41.875 0.0003 0.00

42.875 0.0003 0.00

43.875 0.0003 0.00

44.875 0.0003 0.00

45.875 0.0003 0.00

46.875 0.0003 0.00

47.875 0.0003 0.00

48.875 0.0003 0.00

49.875 0.0003 0.00

50.875 0.0003 0.00

51.875 0.0003 0.00

52.875 0.0003 0.00

53.875 0.0003 0.00

54.875 0.0003 0.00

55.875 0.0003 0.00

56.875 0.0003 0.00

57.875 0.0003 0.00

58.875 0.0003 0.00

59.875 0.0003 0.00

60.875 0.0003 0.00

61.875 0.0003 0.00

62.875 0.0003 0.00

63.875 0.0003 0.00

64.875 0.0003 0.00

65.875 0.0003 0.00

66.875 0.0003 0.00

67.875 0.0003 0.00

68.875 0.0003 0.00

69.875 0.0003 0.00

70.875 0.0003 0.00

71.875 0.0003 0.00

72.875 0.0003 0.00

73.875 0.0003 0.00

74.875 0.0003 0.00

75.875 0.0003 0.00

76.875 0.0003 0.00

77.875 0.0003 0.00
08/11/2026
PH2 605 of 876

ELEVATION -DISCHARGE CALCULAT OR
ORIFICE FLOW (D inches and over)
%PUT
Lower Orifice
Diameter,D=
N.) Upper Orifice
NDiameter,D=
Q)

CALCULATE
Orifice Equation, Q = 0. 67A(2gH)o.s

0.8000

3.0000
inches
inches
DMA -7 (IMP -6)
Lower Orifice Elevation = 0 Feet (0 Inches)
Upper Orifice Elevation = 5.000 Feet (60.00 Inches)

L OWER ORIFICE UPPER ORIFICE L OWER UPPER ORIFICE

ELEVATION A BOVE LOWER ORIFICE ELEVATION ABOVE UPPER ORIFICE EFFECTIVE HEIGHT EFFECTIVE HEIGHT ORIFICE AREA AREA LOWER ORIFICE (in) DISCHARGE (cfs) UPPER ORIFICE (in) DISCHARGE (cfs) H (in) H (in) (sq ft) (sq ft)

LOWER ORIFICE COMBINED ORIFICE

ELEV (FT) DISCHARGE (CFS) ELEV (FT) DISCHARGE (CFS)
1 0. 0038 0 0 0.6 0 0 .003 0.00 0 .0833 0.0038 0 .0833 0.0038 B ottom of AQ 2 0.0061 0 0 1 .6 0 0.003 0 .00 0.1667 0 .0061 0.1667 0 .0061 3 0.0078 0 0 2.6 0 0.003 0.05 0.2500 0.0078 0.2500 0.0078 4 0.0092 0 0 3.6 0 0.003 0.05 0.3333 0.0092 0.3333 0.0092 5 0.0104 0 0 4.6 0 0.003 0.05 0.4167 0.0104 0.4167 0.0104 6 0.0115 0 0 5.6 0 0.003 0.05 0.5000 0.0115 0.5000 0.0115 7 0.0125 0 0 6.6 0 0.003 0.05 0.5833 0.0125 0.5833 0.0125 8 0. 0134 0 0 7.6 0 0 .003 0.05 0 .6667 0.0134 0 .6667 0.0134 9 0.0142 0 0 8.6 0 0.003 0.05 0.7500 0.0142 0.7500 0.0142 10 0.0150 0 0 9 .6 0 0.003 0 .05 0.8333 0 .0150 0.8333 0 .0150 11 0. 0158 0 0 10.6 0 0 .003 0.05 0 .9167 0.0158 0 .9167 0.0158 2 12 0.0165 0 0 11.6 0 0.003 0 .05 1.0000 0 .0165 1.0000 0 .0165 N. .) 13 0.0172 0 0 12. 6 0 0.003 0.05 1.0833 0.0172 1.0833 0.0172 14 0.0179 0 0 13. 6 0 0.003 0.05 1.1667 0.0179 1.1667 0.0179 15 0.0185 0 0 14.6 0 0.003 0.05 1.2500 0.0185 1.2500 0.0185 16 0.0192 0 0 15. 6 0 0.003 0.05 1.3333 0.0192 1.3333 0.0192 Q
0 CO
a)
17 0.0198 0 0 16. 6 0 0.003 0.05 1.4167 0.0198 1.4167 0.0198 Average AQ 18 0. 0204 0 0 17.6 0 0 .003 0.05 1 .5000 0.0204
19 0. 0209 0 0 18.6 0 0 .003 0.05 1 .5833 0.0209
20 0.0215 0 0 19.6 0 0.003 0 .05 1.6667 0 .0215
21 0.0220 0 0 20. 6 0 0 .003 0.05 1.7500 0.0220
22 0.0225 0 0 21.6 0 0.003 0 .05 L8333 0 .0225
23 0.0231 0 0 22. 6 0 0.003 0.05 1.9167 0.0231
24 0.0236 0 0 23. 6 0 0.003 0.05 2.0000 0.0236
25 0.0241 0 0 24.6 0 0.003 0.05 2.0833 0.0241
26 0.0245 0 0 25. 6 0 0.003 0.05 2.1667 0.0245
27 0.0250 0 0 26. 6 0 0.003 0.05 2.2500 0.0250
28 0. 0255 0 0 27.6 0 0. 003 0.05 2 .3333 0.0255
29 0.0259 0 0 28. 6 0 0.003 0.05 2.4167 0.0259
30 0.0264 0 0 29.6 0 0.003 0.05 2.5000 0 .0264
31 0. 0268 0 0 30.6 0 0. 003 0.05 2 .5833 0.0268
32 0.0273 0 0 31.6 0 0.003 0. 05 2.6667 0 .0273
33 0.0277 0 0 32. 6 0 0.003 0.05 2.7500 0.0277 2.7500 0.0277 Top AQ 34 0.0281 0 0 33. 6 0 0.003 0.05 2.8333 0.0281 2.8333 0.0281 35 0.0285 0 0 34.6 0 0.003 0.05 2.9167 0.0285 2.9167 0.0285 36 0.0289 0 0 35. 6 0 0.003 0.05 3.0000 0.0289 3.0000 0.0289 Top Soil 37 0.0294 0 0.0000 36. 6 0 0.003 0.05 3.0833 0.0294 3 .0833 0.0294 1 .5000
1 .5833

1.6667
1 .7500

1.8333

1.9167

2.0000

2.0833

2.1667

2.2500
2 .3333

2.4167

2.5000
2 .5833

2.6667

0.0204

0.0209
0 .0215

0.0220
0 .0225

0.0231

0.0236

0.0241

0.0245

0.0250

0.0255

0.0259
0 .0264

0.0268
0 .0273

9ME/1 L/80
38 0 .0298 0 0.0000 37 .6 0 0.003 0 .05 3 .1667 0.0298
39 0.0301 0 0.0000 38.6 0 0.003 0.05 3.2500 0.0301
40 0 .0305 0 0.0000 39 .6 0 0.003 0 .05 3.3333 0 .0305
41 0.0309 0 0.0000 40 .6 0 0.003 0.05 3.4167 0.0309
42 0.0313 0 0 .0000 41.6 0 0.003 0.05 3.5000 0.0313
43 0.0317 0 0.0000 42.6 0 0 .003 0.05 3.5833 0.0317
44 0.0320 0 0.0000 43 .6 0 0.003 0 .05 3 .6667 0 .0320

3.1667
3 .2500

3.3333
3 .4167
3 .5000

3.5833

3.6667

0.0298

0.0301

0.0305

0.0309

0.0313

0.0317
0 .0320
45 0.0324 0 0 .0000 44.6 0 0.003 0 .05 3 .7500 0.0324 3.7500 0.0324 Average Soil 46 0.0328 0 0.0000 45.6 0 0.003 0.05 3.8333 0.0328 3.8333 0.0328 47 0.0331 0 0.0000 46.6 0 0.003 0.05 3.9167 0.0331 3 .9167 0.0331 48 0.0335 0 0.0000 47 .6 0 0.003 0.05 4 .0000 0.0335 4.0000 0.0335 49 0.0338 0 0.0000 48 .6 0 0.003 0.05 4.0833 0.0338 4.0833 0.0338 50 0. 0342 0 0 .0000 49 .6 0 0.003 0 .05 4 .1667 0.0342 4.1667 0 .0342 51 0.0345 0 0.0000 50 .6 0 0.003 0.05 4.2500 0.0345 4.2500 0.0345 52 0.0349 0 0 .0000 51.6 0 0.003 0.05 4 .3333 0.0349 4.3333 0.0349 53 0. 0352 0 0.0000 52 .6 0 0 .003 0 .05 4.4167 0 .0352 4.4167 0 .0352 54 0.0355 0 0.0000 53 .6 0 0.003 0 .05 4 .5000 0 .0355 4 .5000 0 .0355 Top Mulch 55 0.0359 0 0.0000 54 .6 0 0.003 0 .05 4.5833 0.0359 4 .5833 0.0359 56 0.0362 0 0.0000 55.6 0 0.003 0.05 4.6667 0.0362 4.6667 0.0362 57 0.0365 0 0.0000 56.6 0 0.003 0.05 4.7500 0.0365 4.7500 0.0365 Tope Surface 58 0. 0368 0 0.0000 57 .6 0 0.003 0.05 4 .8333 0 .0368 4 .8333 0 .0368 59 0.0371 0 0. 0000 58 .6 0 0.003 0.05 4 .9167 0.0371 4 .9167 0.0371 60 0.0375 0 0.0000 59 .6 0 0.003 0 .05 5 .0000 0 .0375 5 .0000 0 .0375 61 0.0378 1 0. 0682 60.6 1 0.003 0 .05 5.0833 0.0378 5.0833 0.1060 62 0. 0381 2 0. 0965 61.6 2 0.003 0.05 5.1667 0.0381 5 .1667 0.1346 Ave Surface TJ 63 0. 0384 3 0. 0836 62.6 1.5 0.003 0.05 5 .2500 0.0384 5 .2500 0.1220 = 64 0.0387 4 0. 1079 63.6 2.5 0.003 0.05 5 .3333 0.0387 5 .3333 0.1466 N 65 0.0390 5 0.1276 64.6 3.5 0.003 0.05 5.4167 0.0390 5.4167 0.1666 66 0.0393 6 0.1447 65.6 4.5 0.003 0.05 5.5000 0.0393 5.5000 0.1840 67 0. 0396 7 0.1600 66.6 5.5 0.003 0.05 5.5833 0.0396 5.5833 0.1996 Surface P oind @ 10" 68 0.0399 8 0. 1740 67. 6 6.5 0.003 0 .05 5 .6667 0.0399 69 0.0402 9 0. 1869 68. 6 7.5 0.003 0.05 5 .7500 0.0402 70 0.0405 10 0.1989 69. 6 8.5 0.003 0.05 5 .8333 0 .0405 71 0.0408 11 0.2103 70.6 9.5 0.003 0.05 5 .9167 0.0408
72 0. 0411 12 0.2211 71.6 10.5 0.003 0.05 6 .0000 0.0411 73 0. 0413 13 0.2314 72.6 11.5 0.003 0.05 6.0833 0.0413 74 0. 0416 14 0.2412 73. 6 12. 5 0.003 0.05 6 .1667 0.0416 75 0. 0419 15 0.2507 74. 6 13.5 0.003 0.05 6.2500 0 .0419 76 0.0422 16 0.2598 75. 6 14.5 0.003 0.05 6.3333 0.0422 77 0.0425 17 0. 2686 76.6 15.5 0.003 0.05 6.4167 0.0425 78 0.0427 18 0.2772 77. 6 16. 5 0.003 0.05 6 .5000 0 .0427 919 4° L09

5.6667

5.7500
5 .8333
5 .9167
6 .0000

6.0833

6.1667

6.2500

6.3333

6.4167
6 .5000
0 .2138

0.2270
0 .2394

0.2511

0.2621

0.2727

0.2829

0.2926

0.3020

0.3111
0 .3199

POC-1
7 08/11/2026
PH2 608 of 876

9Z0Z/ I. 1. /90
91840 609
4-
U
0 LL

0. 400

0. 350

0.300

0.250

0.200

0.150

0.100

0.050
Flow Duration Curve
[Pre vs . Post (Mitigated)]

0.000

0.0%

0. 0%

0.1%
1 -Pre -project Q
Post -project (Mitigated) Q

0.0%
% Time Exceeding
1 .0%

Q2 to Q10 Comparison Table- POC-1
Return Period
Existing Condition (cfs)
Mitigated Condition
(cfs)
Reduction, Exist -
Mitigated (cfs)
2 -year

0.230

0.151

0.079
3 -year

0.249

0.191

0.059
4 -year

0.285

0.232

0.053
5 -year

0.294

0.263

0.031
6 -year

0.301

0.275

0.026
7 -year

0.317

0.293

0.024
8 -year

0.325

0.304

0.021
9 -year

0.351

0.315

0.036
10 -year

0.377

0.335

0.042
9 08/11/2026
PH2 610 of 876

Lower Flow
Threshold:
10%

0.1xO2 (Pre):

0.023
cfs
O10 (Pre):

0.3769
cfs
# of Ordinates:
gg
Incremental Q (pre)

0.0036
cfs
Total Houly Data:
499320
hours
Interval
Pre -project
Flow (cfs)
Pre -Project
Hours
Pre -project %
Time Exceeding
Post -Project
Hours
Post -project %
Time Exceeding
Percentage
Pass?Fail
1 0.023
883

0.2%
599

0.12%
68 pass
2 0.027
883

0.2%
599

0.12%
68 pass
3 0.030
698

0.1%
343

0.07%
49 pass
4 0.034
698

0.1%
343

0.07%
49 pass
5 0.037
698

0.1%
343

0.07%
49 pass
6 0.041
592

0.1%
252

0.05%
43 pass
7 0.044
592

0.1%
252

0.05%
43 pass
8 0.048
592

0.1%
252

0.05%
43 pass
9 0.052
497

0.1%
201

0.04%
40 pass
10 0.055
497

0.1%
201

0.04%
40 pass
11 0.059
497

0.1%
201

0.04%
40 pass
12 0.062
401

0.1%
163

0.03%
41 pass
13 0.066
401

0.1%
163

0.03%
41 pass
14 0.069
401

0.1%
163

0.03%
41 pass
15 0.073
316

0.1%
117

0.02%
37 pass
16 0.077
316

0.1%
117

0.02%
37 pass
17 0.080
284

0.1%
102

0.02%
36 pass
18 0.084
284

0.1%
102

0.02%
36 pass
19 0.087
284

0.1%
102

0.02%
36 pass
20 0.091
240

0.0%
84 0.02%
35 pass
21 0.094
240

0.0%
84 0.02%
35 pass
22 0.098
240

0.0%
84 0.02%
35 pass
23 0.102
202

0.0%
69 0.01%
34 pass
24 0.105
202

0.0%
69 0.01%
34 pass
25 0.109
202

0.0%
69 0.01%
34 pass
26 0.112
154

0.0%
59 0.01%
38 pass
27 0.116
154

0.0%
59 0.01%
38 pass
28 0.120
154

0.0%
59 0.01%
38 pass
29 0.123
129

0.0%
56 0.01%
43 pass
10 08/11/2026
PH2
611 of 876

30 0.127
129

0.0%
56 0.01%
43 pass
31 0.130
116

0.0%
49 0.01%
42 pass
32 0.134
116

0.0%
49 0.01%
42 pass
33 0.137
116

0.0%
49 0.01%
42 pass
34 0.141
99 0.0%
38 0.01%
38 pass
35 0.145
99 0.0%
38 0.01%
38 pass
36 0.148
99 0.0%
38 0.01%
38 pass
37 0.152
82 0.0%
32 0.01%
39 pass
38 0.155
82 0.0%
32 0.01%
39 pass
39 0.159
82 0.0%
32 0.01%
39 pass
40 0.162
67 0.0%
30 0.01%
45 pass
41 0.166
67 0.0%
30 0.01%
45 pass
42 0.170
67 0.0%
30 0.01%
45 pass
43 0.173
62 0.0%
28 0.01%
45 pass
44 0.177
62 0.0%
28 0.01%
45 pass
45 0.180
51 0.0%
23 0.00%
45 pass
46 0.184
51 0.0%
23 0.00%
45 pass
47 0.187
51 0.0%
23 0.00%
45 pass
48 0.191
44 0.0%
20 0.00%
45 pass
49 0.195
44 0.0%
20 0.00%
45 pass
50 0.198
44 0.0%
20 0.00%
45 pass
51 0.202
41 0.0%
19 0.00%
46 pass
52 0.205
41 0.0%
19 0.00%
46 pass
53 0.209
41 0.0%
19 0.00%
46 pass
54 0.212
39 0.0%
19 0.00%
49 pass
55 0.216
39 0.0%
19 0.00%
49 pass
56 0.220
39 0.0%
19 0.00%
49 pass
57 0.223
36 0.0%
18 0.00%
50 pass
58 0.227
36 0.0%
18 0.00%
50 pass
59 0.230
30 0.0%
15 0.00%
50 pass
60 0.234
30 0.0%
15 0.00%
50 pass
61 0.237
30 0.0%
15 0.00%
50 pass
62 0.241
22 0.0%
14 0.00%
64 pass
63 0.245
22 0.0%
14 0.00%
64 pass
64 0.248
22 0.0%
14 0.00%
64 pass
65 0.252
21 0.0%
13 0.00%
62 pass
66 0.255
21 0.0%
13 0.00%
62 pass
67 0.259
21 0.0%
13 0.00%
62 pass
68 0.263
21 0.0%
12 0.00%
57 pass
11 08/11/2026
PH2
612 of 876

69 0.266
21 0.0%
12 0.00%
57 pass
70 0.270
21 0.0%
12 0.00%
57 pass
71 0.273
20 0.0%
10 0.00%
50 pass
72 0.277
20 0.0%
10 0.00%
50 pass
73 0.280
15 0.0%
8 0.00%
53 pass
74 0.284
15 0.0%
8 0.00%
53 pass
75 0.288
15 0.0%
8 0.00%
53 pass
76 0.291
10 0.0%
8 0.00%
80 pass
77 0.295
10 0.0%
8 0.00%
80 pass
78 0.298
10 0.0%
8 0.00%
80 pass
79 0.302
9 0.0%
7 0.00%
78 pass
80 0.305
9 0.0%
7 0.00%
78 pass
81 0.309
9 0.0%
7 0.00%
78 pass
82 0.313
8 0.0%
6 0.00%
75 pass
83 0.316
8 0.0%
6 0.00%
75 pass
84 0.320
8 0.0%
6 0.00%
75 pass
85 0.323
7 0.0%
5 0.00%
71 pass
86 0.327
7 0.0%
5 0.00%
71 pass
87 0.330
6 0.0%
5 0.00%
83 pass
88 0.334
6 0.0%
5 0.00%
83 pass
89 0.338
6 0.0%
5 0.00%
83 pass
90 0.341
6 0.0%
5 0.00%
83 pass
91 0.345
6 0.0%
5 0.00%
83 pass
92 0.348
6 0.0%
5 0.00%
83 pass
93 0.352
6 0.0%
5 0.00%
83 pass
94 0.355
6 0.0%
5 0.00%
83 pass
95 0.359
6 0.0%
5 0.00%
83 pass
96 0.363
6 0.0%
5 0.00%
83 pass
97 0.366
6 0.0%
5 0.00%
83 pass
98 0.370
6 0.0%
5 0.00%
83 pass
99 0.373
5 0.0%
5 0.00%
100
pass
100

0.377
5 0.0%
5 0.00%
100
pass
12 08/11/2026
PH2 613 of 876

SWMM Input Data in Input Format
(Existing & Proposed Models)
13 08/11/2026
PH2 614 of 876

PRE-DEV INPUT (POC-1)
[TITLE]
;;Project Title/Notes
[OPTIONS]
;;Option Value
FLOW_UNITS CFS
INFILTRATION GREEN_AMPT
FLOW_ROUTING KINWAVE
LINK_OFFSETS DEPTH
MIN_SLOPE 0
ALLOW_PONDING NO
SKIP_STEADY_STATE NO
START_DATE 08/28/1951
START_TIME 05:00:00
REPORT_START_DATE 08/28/1951
REPORT_START_TIME 05:00:00
END_DATE 05/23/2008
END_TIME 23:00:00
SWEEP_START 01/01
SWEEP_END 12/31
DRY_DAYS 0
REPORT_STEP 01:00:00
WET_STEP 00:15:00
DRY_STEP 04:00:00
ROUTING_STEP 0:01:00
RULE_STEP 00:00:00
INERTIAL_DAMPING PARTIAL
NORMAL_FLOW_LIMITED BOTH
FORCE_MAIN_EQUATION H -W
VARIABLE_STEP 0.75
LENGTHENING_ STEP 0
MIN_SURFAREA 12.557
MAX_TRIALS 8
HEAD_TOLERANCE 0.005
SYS_FLOW_TOL 5
LAT_FLOW_TOL 5
MINIMUM_STEP 0.5
THREADS 1
14 08/11/2026
PH2 615 of 876

9Z0Z/ L 1./80
9L8409L9
[EVAPORATION]
;;Data Source Pa ramete rs
;;

MONTHLY
DRY_ONLY

0.06 0.08 0.110 0 .15 0 .17 0 .19 0 .19 0.18 0 .15 0 .11 0 .08 0 .06 NO
[RAINGAGES]
;;Name Fo rm at Interval SCF S ource
;;
Oceanside INTENSITY 1:00 1.0 TIMESERIES Oceansid e
[SUBCATCHMENTS]
;;Nam e
;;
Basins_1-4
Rain Gage
Outlet
Area %Imp ery Width %Slope CurbLen SnowP ack
Oce anside POC-1

0.43 0 193 8 0
[SUBAREAS]
;;Subcatchm ent N-Im pery N-Per y S-Impery S-Pery PctZer o RouteTo PctRouted ;;
Basins_1-4 0. 012 0.15 0. 05 0.1 25 OUTLET
[INFILTRATION]
;;Subcatchment Param l Param 2 Para m3 Param 4 Para m5
;;
Basins_1-4 9 0.025 0. 30 7 0
[OUTFALLS]
;;Name
;;
POC-1 0 FREE ND
[TIMESERIES]
;;Name Date Time Value
;;
Oceanside FILE "Z:\Projects\2023\23-221\PROD\Reports\WQMP\SWIV4\oceanside.dat" Elevation Type Stage Data Gated Route To
15 [REPORT]
;;Reporting Options

SUBCATCHMENTS ALL

NODES ALL

LINKS ALL
[TAGS]
[MAP]
DIMENSIONS -966.709 0.000 10966.709 10000.000
Units None
[COORDINATES]
;;Node
;;
POC-1 -367.616 582.482
X-Coord Y-Coord
[VERTICES]
;;Link
;;
X-Coord Y-Coord
[Polygons]
;;Subcatchment
;;
Basins_1-4
Basins_1-4
Basins_1-4
Basins_1-4
[SYMBOLS]
;;Gage
;;
Oceanside -445.129 623.600
X-Coord Y-Coord
- 494.717
- 442.956
- 439.819
- 494.717
551.400
551.400
598.455
600.024
X-Coord Y-Coord
16 08/11/2026
PH2 617 of 876

POST-DEV INPUT (POC-1)
[TITLE]
;;Project Title/Notes
[OPTIONS]
;;Option Value
FLOW_UNITS CFS
INFILTRATION GREEN_AMPT
FLOW_ROUTING KINWAVE
LINK_OFFSETS DEPTH
MIN_SLOPE 0

ALLOW PONDING NO
SKIP_STEADY STATE NO
START_DATE 08/28/1951
START_TIME 05:00:00
REPORT START DATE 08/28/1951
REPORT_START_TIME 05:00:00
END_DATE 05/23/2008
END_TIME 23:00:00
SWEEP_START 01/01
SWEEP_END 12/31
DRY_DAYS 0
REPORT_STEP 01:00:00
WET_STEP 00:15:00
DRY_STEP 04:00:00
ROUTING_STEP 0:01:00
RULE_STEP 00:00:00
INERTIAL_DAMPING PARTIAL
NORMAL_FLOW_LIMITED BOTH
FORCE_MAIN_EQUATION H -W
VARIABLE_STEP 0.75
LENGTHENING_STEP 0
MIN_SURFAREA 12.566
MAX_TRIALS 8
HEAD_TOLERANCE 0.005
SYS_FLOW_TOL 5
LAT_FLOW_TOL 5
MINIMUM_STEP 0.5
THREADS 4
17 08/11/2026
PH2 618 of 876

[EVAPORATION]
;;Data Source Parameters
;;

MONTHLY
DRY_ONLY
.06 .08 .11 .15 .17 .19 .19 .18 .15 .11 .08 .06
NO
[RAINGAGES]
;;Name Format Interval SCF Source
;;
Oceanside INTENSITY 1:00 1.0 TIMESERIES Oceanside
[SUBCATCHMENTS]
;;Name
;;
POST_DMA-1 Oceanside IMP -1 0.137 21.6 156 2.5 0
IMP -1 Oceanside POC-1 0.0027778 0 10 0 0
POST_DMA-3 Oceanside IMP -3 0.108 59.8 98 2.5 0
IMP -3 Oceanside POC-1 0.00500 0 10 0 0
POST_DMA-2 Oceanside POC-1 0.094 20.24 67 9 0
POST_DMA-4 Oceanside POC-1 0.089 0 243 33 0
Rain Gage
Outlet
Area %Impery Width %Slope CurbLen SnowPack
[SUBAREAS]
;;Subcatchment N-Impery N-Pery S-Impery S-Pery PctZero RouteTo PctRouted ;;
POST_DMA-1 0.012 0.15 0.05 0.1 25 OUTLET
IMP -1 0.012 0.15 0.05 0.1 25 OUTLET
POST_DMA-3 0.012 0.1S 0.05 0.1 25 OUTLET
IMP -3 0.012 0.15 0.05 0.1 25 OUTLET
POST_DMA-2 0.012 0.15 0.05 0.1 2S OUTLET
POST_DMA-4 0.012 0.15 0.05 0.1 25 OUTLET
[INFILTRATION]
;;Subcatchment Paraml Param2 Param3 Param4 ParamS
;;
POST_DMA-1 9 0.01875 0.3 7 0
IMP -1 1.5 0.3 0.33 7 0
POST_DMA-3 9 0.01875 0.3 7 0
IMP -3 1.5 0.3 0.33 7 0
POST_DMA-2 1.5 0.3 0.33 7 0
POST_DMA-4 9 0.01875 0.3 7 0
[LID_CONTROLS]
;;Name Type/Layer Parameters
;;
IMP -1 BC
IMP -1 SURFACE 10 0.0 0 0 5
IMP -1 SOIL 24 0.4 0.2 0.1 5 5 1.5
IMP -1 STORAGE 15 0.67 0 0
IMP -1 DRAIN 0.1734 0.5 3 6 0 0
IMP -3 BC
IMP -3 SURFACE 10 0.0 0 0 5
IMP -3 SOIL 24 0.4 0.2 0.1 5 5
IMP -3 STORAGE 15 0.67 0 0
IMP -3 DRAIN 0.0963 0.5 3 6 0 0

1.S
18 08/11/2026
PH2 619 of 876

CD[LID_USAGE]
�;;Subcatchment LID Proc ess Numbe r A rea Width InitSat Fromlmp ToPery RptFile DrainTo Fro mPe ry
IMP -1 IMP -1 1 121.00 0 0 100 0
NJ
cD INP-3 IMP -3 1 217.80 0 0 100 0
N
0)[OUTFALLS]
;;Name Elevation Type Stage Data Gated R oute To
;;
POC-1 0 FREE NO
POC-1 0
POC-1 0
[TIMESERIES]
;;Nam e Date Time Value
;;
Oceanside FILE "C:\Users\m assy.fatini\DC\ACCDocs\SWS Engine ering\2023\Pr oject Files\23-299\PROD\Repo rts\WQMP\SW MM\oceansid e Raingauge\oceanside .dat" [REPORT]
;;Reporting Options

INPUT YES

SUBCATCHMENTS ALL

NODES ALL

LINKS ALL
2 N [TAGS]
919 4° OZ9

[MAP]
DIMENSIONS -129.191 -319.762 933.945 189.693
Units Feet
[COORDINATES]
;;Node
;;
POC-1 357.977 112.874
X-Coord Y-Coord
[VERTICES]
;;Link
;;
X-Coord Y-Coord
[Polygons]
;;Subcatchment X-Coord Y-Coord
d J'
POST_DMA-1
POST_DMA-1
POST_DMA-1
POST_DMA-1
IMP -1
IMP -1
IMP -1
IMP -1
POST_DMA-3
POST_DMA-3
POST_DMA-3
POST_DMA-3
IMP -3
IMP -3
IMP -3
IMP -3
IMP -3
POST_DMA-2
POST_DMA- 2
POST_DMA-2
POST_DMA- 2
POST_DMA-4
POST_DMA-4
POST_DMA-4
POST_DMA-4
[SYMBOLS]
;;Gage
;;
Oceanside 237.533 183.321

11.872
108.689
107.455

10.022

43.322

92.655

39.005
393.566
395.434
299.577
296.465
343.382
386.331
390.066
342.760
342.760
250.857
251.671
156.356
156.356
542.977
547.294
467.744
465.277
- 194.843
- 194.843
-128.243
-130.710

4.495

3.878
- 30.039
- 27.572
- 125.452
- 192.677
- 195.166
- 127.942

21.775

21.775
- 17.439
- 18.061

10.571
- 132.000
- 189.026
- 189.841
- 130.370
- 127.626
- 180.660
- 186.210
- 128.243
X-Coord Y-Coord
20 08/11/2026
PH2 621 of 876

PRE -DEVELOPMENT CONDITION (POC-1)
Oceanside
E
POC-1
21 08/11/2026
PH2 622 of 876

Rain Gage Oceanside
Property
Valve
Name
Oceanside
X -Coordinate
-457.027
Y -Coordinate
629,462
Description
Tag
Rain Format

INTENSITY
Time Interval
1;00
Snow Catch Factor
1,t'
Data Source

TIMESERIES
TIME SERIES:
- Series Name
DATA FILE:
- File Name
Oceanside
- Station ID
- Rain Units IN
Outfall POC-1
Property
Value
Name
ROC -1
X -Coordinate
-381.439
Y -Coordinate
585.194
Description
Tag
Inflows
NO
Treatment
NO
Invert El.

D
Tide Gate
NO
Route To
Type
FREE
Fixed Outfall
Fixed Stage
Tidal Outfall
Curse r1ame
Time Series Outfall
Series flame
22 08/11/2026
PH2 623 of 876

Subcatchment Basins_1-4
Property
Value
Name
Basins_1-4
X -Coordinate
-468.052
Y -Coordinate
575.320
Description
Tag
Rain Gage
Oceanside
Outlet
POC-1
Area

0.43 Width
193
%Slope
8 % Irnpery
0 N-Impery

0.012
N-Pery

0.15 Dstore-Impery

0.05 Dstore-Pery

0.1 %Zero-Impery
25 Subarea Routing
OUTLET
Percent Routed
100
Infiltration Data
GREEN_AMPT
Groundwater
NO
Snow Pack
LID Controls
0 Land Uses
0 Initial Buildup
NONE
Curb Length
0 N-Pery Pattern
Dstore Pattern
Infil. Pattern
Infiltration Editor X
Infiltration Method
GREEN_AMPT
Property
Value
Suction Head
g
Conductivity
0,025
Initial Deficit
0,30
Soil capillary suction head (inches or mm)
23 08/11/2026
PH2 624 of 876

POST -DEVELOPMENT CONDITION (POC-1)
Oceanside
P C-1
24 08/11/2026
PH2 625 of 876

Subcatchment POST DMA
-1 x
Property
Value
Name
iP0ST DMA -1
L
X -Coordinate

59.510
Y -Coordinate
-162.160
Description
Tag
Rain Gage
Oceanside
Outlet
IMP -1
Area

0.137
Width
156
°,% Slope

2.5 % I mpery

21.6 N-Impery

0.012
N-Perw

0.15 Dstore-Impery

0.05 Dstore-Penn

0.1 Zerc-Imper.,
25 Subarea Routing
OUTLET
Percent Routed
100
Infiltration Data

GREEN AMPT
Groundwater
NO
Snow Pack
LID Controls
0 Land Uses
0 Initial Buildup
NONE
Curb Length
0 N-Perw Pattern
Dstore Pattern
Infil. Pattern
Infiltration Editor X
Infiltration Method
GREEN_AMPT
Property
Value
Suction Head
g

0.01875
Conductivity
Initial Deficit

0.3 Soil capillary suction head (inches or mm)
25 08/11/2026
PH2 626 of 876

Property
Value
Name
IMP -1
X-coordinate

16.909
��--12.310
1/ -coordinate
Description
Tag
Rain Gage
Oceanside
Outlet
POC-1
Area

0.002777$
Width
10 % Slope
0 % I mpery
0 N-Impery

0.012
N-Pery

0.15 Dstore-Impery

0.05 Dstore-Pery

0.1 %Zero-Impery
25 Subarea Routing
OUTLET
Percent Routed
100
Infiltration Data
GREEN_AMPT
Groundwater
NO
Snow Pack
LID Controls
1 Land Uses
0 Initial Buildup
NONE
Curb Length
0 N -Dery Pattern
Dstore Pattern
Infil. Pattern
Infiltration Editor X
Infiltration Method GREEN_AMPT
Property
Value
Suction Head

11.5 0.3
Conductivity
Initial Deficit

6.33 Soil capillary suction head (inches or mm)
26 08/11/2026
PH2 627 of 876

LID Usage Editor
LID Control Name
IMP -1
Detailed Report File (Optional)
❑ LID Occupies Full Subcatchment
Area of Each Unit (sq ft or sq m)
Number of Units
% of Subcatchment Occupied
Surface Width per Unit (ft or m)
% Initially Saturated
% of Impervious Area Treated
% of Pervious Area Treated
121.1©
1 100.0
0 0
106
0 Send Drain Flow To:
(Leave blank to use subcatchment outlet)
POC-1
❑ Return all Outflow to Pervious Area
OK.

Cancel Help
27 08/11/2026
PH2 628 of 876

9Z0Z/ I. 1. /90
918 40 6Z9
LID Control Editor
Co ntrol Name:

Drain -
IMP -1
Bio-Retention Cell
*Option al
Can cel
Surface Soil Storage Drain
Berm Height
(in. or mm)
Vegetation Volume
Fraction
Surface Roughness
(Mannings n)
Surface Slope
(percent)
10 0 .0
0 0
LID Co ntro l Editor
Control Name:

LID Type:
1 IM P -1
Bio-Retention Cell
v
So il
Storage
*Optio nal
Drain '
OK Cancel Help
Surface So il
Sto rage Drain
Thickness
(in. or mm)
Void Ratio
(Vo ids / Solids)
Seepage Rate
(in/hr or mm/hr)
Clogging Factor
15 0.67
0 0
X
LID C ontr ol Editor
Control Name:

LID Type:

OK
IMP -1
Bio-Retenti on Cell
*Optional
Chai n`
Cancel Help
Surface Soil Storage Drain
Thickness
(in, or mm)
Por osity
(volume fraction)
Field Capacity
(volume fracti on)
Wilting Point
( volume fraction)
Conducti vity
(in/hr or mm/hr)
Conductivity
Slope
Sucti on Head
(in. or mm)
24 0.4

0.2 0.1
5 5

1.5 X
LID Control Editor
Control Name:

LID Type:
28 Bio-Retention Cell
S urfac e
— r
Storage
'Optional
OK Cancel Help
Surface S oil
Fl ow Coefficient*
Flow Exponent
Offset (in or mm)
St orage Drai n
Ope n Le vel (in or mm)
Closed L evel (in or mm)
C ontrol Curve
Drain Advisor
*Fl ow is in in/hr or mm/hr, use 0 if
there is no drain.

Subcatchment POST DMA -2
©�
Property Value
Name
P OSTDMA-2
.X -Coordinate
203.210
V -Coordinate
-160.309
Description
Tag
Rain Gage Oceanside
Outlet
P OC-1
. Area
D.094
Width
67 % Slope 9
Impery

20.24 N-Impery
0:012
N-Pery

0.15 Dstore-lmpery

0.05 Dstore-Pery

0.1 %Zero-Imper.'
25 Subarea Routing
OUTLET
Percent Routed
100
Infiltration Data
GREEN_AMPT
Groundwater
NO
Snow Pack
I
LID Controls
'0
0 ...

Land Uses
Initial Buildup
NONE
Curb Length
0 N-Pery Pattern
Dstore Pattern
F
Infil, Pattern
Infiltration Editor X
Infiltration Method
GREEN_AMPT ,
Property
Value
Suction Head
9 Conductivity
0,01875
Initial Deficit
0,30
Soil capillary suction head (inches or mm)
08/11/2026
PH2 630 of 876

Subcatchment POST DMA -3
Property
Value
Name
POST DMA -3
X -Coordinate
346261
Y -Coordinate
-160,309
Description
Tag
Rain Gage
Oceanside
Outlet
IMP -3
Area

0.108
Width
98 % Slope

2.5 % Impery

59.8 N-Impery

0.012
h4 -Peru
0,15
Dstore-Impery

0.05 Dstore-Pery

0.1 %Zero-Impenr
?5
Subarea Routing
OUTLET
Percent Routed
100
Infiltration Data

GREEN AMPT
Groundwater
NO
Snow Pack
LID Controls
0 Land Uses
0 Initial Buildup
NONE
Curb Length
0 N-Pery Pattern
Dstore Pattern
Infil, Pattern
Infiltration Editor X
Infiltration Method
GREEN_AMPT
Property
Value
Suction Head
9 Conductivity
0,01875
Initial Deficit
0,3.0
Soil capillary suction head finches or mm)
08/11/2026
PH2 631 of 876

Subcatchrnent IMP -3 x
Property
Value
Name IMP -3
X -Coordinate 361.060
V -Coordinate 3.724
Description
Tag
Rain Gage
Oceanside
Outlet
POC-1
Area

0.00500
Width
10 %Slope
0 % Impery
0 N-Impery

0.012
N-Pery

0.15 Dstore-Impery 10.05
Dstore-Pery
,0.1
%Zero-Impery
25 Subarea Routing OUTLET
Percent Routed
100
GREEN_AMPT
NO
Infiltration Data
Groundwater
Snow Pack
LID Controls
Land Uses
1 0
Initial Buildup NONE
Curb Length
N -Peru Pattern
Dstore Pattern
Infil, Pattern
Infiltration Editor X
Infiltration Method
GREEN_AMPT
Property
Value
Suction Head
1,5
Conductivity
0,3
Initial Deficit
0,33
Soil capillary suction head (inches or mm)
08/11/2026
PH2
632 of 876

LID Wage Editor
LID Control Name
Detailed Report File (Optional)
❑ LID Occupies Full Subcatchment
Area of Each Unit (sq ft or sq m)
Number of Units
% of Subcatchment Occupied
Surface Width per Unit (ft or m)
% Initially Saturated
% of Imperious Area Treated
of Pervious Area Treated
217.80
1 100.0
0 0
100
0 Send Drain Flow To:
(Leave blank to use subcatchment outlet)
POC-1
❑ Return all Outflow to Pervious Area
OK
Cancel Help
08/11/2026
PH2 633 of 876

9Z0Z/ I. 1. /80
919 40 1789
LIL' -ntrol Editor
Control Name:

LID Type:

Soil
I MP -3
Bio-Retenti on Cell
Surface
Storage
OK
'Optional
Cancel
Drain'
Help
Surface Soil St orage Drain
Berm Height
(in. or mm)
Vegetation Vol ume
Fractio n
Surface R oughness
(Mannings n)
Surface Slope
(percent)
10 0.0
0 0
LID Contro l Editor
Control Name:

LID Type:
*Optio nal
LE M
Bio-Retentio n Cell
Dra in'
OK Can cel Help
Surface So il
Storage Drain
Thickness
(in . or mm)
Void Ratio
(Vo ids/ Solids)
Seepage Rate
(in/hr or mm/hr)
Clogging Facto r
15 0.67
0 0
LID Contr ol Edit or
Control Name:

LID Type:

I
Bio-Retention Cell
Surfac e
f
Soil
St orag e
OK
*Opti onal
Cancel
Drai n'
Help
Surface S oil St orage Drain
Thickness
(in. or mm)
P orosity
( volume fracti on)
Field C apacity
(volume fraction)
Wilting P oint
(volume fracti on)
Conductivity
(in/hr or mm/hr)
Cond uctivity
Sl ope
Suction Head
(in. or mm)
24 0.4
02 0.1
5 5
1 .5
LID C ontr ol Edit or
C ontrol Name:

LID Type:
1 Soil
Bio-Rete ntion Cell
S urf
Stcraz e
" Optional
Drain"
OK Cancel Help
Surface Soil Storage Drain
Flow Coefficient"
Flow Exp onent
Offset (in or mm)
Open Level (in or mm)
Closed Le vel (in or mm)
Contr ol Curve

0.0%3

0.5 3
0 0
Drain Ad visor
"Flow is in in/hr or mm/hr use 0 if
there is no drain.

X
33 Subcatchment PC)ST_DPv1A.-4
Property
Value
Name
NUSLEAN/EA-4
X -Coordinate
505.823
Y -Coordinate
-155.585
Description
Tag
Rain Gage
Oceanside
Outlet
POC-1
Area

0.089
Width
243
% Slope
33 % Impery
0 N-Impery

0.012
N-Pery

0.15 Dstore-Impery
.0.05
Dstore-Pery
:0.1
%Zero-Imper:
25 Subarea Routing
OUTLET
Percent Routed
100
Infiltration Data
GREEN_AMPT
Groundwater
NO
Snow Pack
LID Controls
0 Land Uses
0 Initial Buildup
NONE
Curb Length
0 N-Pery Pattern
Dstore Pattern
In€il, Pattern
Infiltration Editor X
Infiltration Method
GREEN_AMPT
Property
Value
Suction Head
9 Conductivity

0.01875
Initial Deficit

0.30 Soil capillary suction head (inches or mm)
08/11/2026
PH2
635 of 876

Summary Files from the SWMM Model
35 08/11/2026
PH2 636 of 876

PRE-DEV OUTPUT (POC-1)
*********************************************> _K-******** NOTE: The summary statistics displayed in this report are based on results found at every computational time step, not just on results from each reporting time step.
*************s*************** ***********************s**** ****************
Analysis Options
****************
Flow Units CFS
Process Models:

Rainfall/Runoff YES

RDII NO
Snowmelt NO
Groundwater NO
Flow Routing NO
Water Quality NO
Infiltration Method GREEN_Ah1PT
Starting Date 08/28/1951 05:00:00
Ending Date 05/23/2008 23:80:00
Antecedent Dry Days 0.0
Report Time Step 01:00:00
Wet Time Step 00:15:00
Dry Time Step 04:00:00
***********************.yx Volume Depth
Runoff Quantity Continuity acre-feet inches
**************************
Total Precipitation
Evaporation Loss
Infiltration Loss
Surface Runoff
Final Storage
Continuity Error (%)
**************************
Flow Routing Continuity
**************************

24.191 675.110

0.899 25.096

18.350 512.088

5.462 152.423

0.000 0.001
-2.148
Volume Volume
acre-feet 10^6 gal
Dry Weather Inflow 0.000 0.000
Wet Weather Inflow 5.462 1.780
Groundwater Inflow 0.000 0.000
RDII Inflow 0.000 0.000
External Inflow 0.000 0.000
External Outflow 5.462 1.780
Flooding Loss 0.000 0.000
Evaporation Loss 0.000 0.000
Exfiltration Loss 0.000 0.000
Initial Stored Volume 0.000 0.000
Final Stored Volume 0.000 0.000
Continuity Error (%) 0.000
36 08/11/2026
PH2 637 of 876

9Z0Z/ L- L-/80
2 N
0)
CO
CO
0 CO
CA
** ** ** ** ********* **** **** **
Subcatchment Runoff Sum mary
** ** ******** ***** **** ** ** **
Subcatchment
Total Total Total T otal I mpery Pery Total Total Peak Runoff Precip Runon Evap Infil Runoff Runoff Runoff Runoff Runoff Coeff in in in in in in in 10'`6 gal CFS
Basins_1-4 675.11

0.00 25.10
Analysis begun an: Tue Mar 4 08:39:26 2025
Analysis ended on: Tue Mar 4 08:39:39 2025
Total elapsed time: 00:00:13
512.09 0.00
152 .42 152 .42
1 .78 0.48 0.226
37 POST-DEV OUTPUT (POC-1)
EPA STORM WATER MANAGEMENT MODEL - VERSION S.1 (Build 5.1.015) *************
Element Count
*************
Number of rain gages 1
Number of subcatchments 6
Number of nodes 1
Number of links 0
Number of pollutants 0
Number of land uses 0
Raingage Summary
****************
Name
Data Source
Data
Type
Recording
Interval
Oceanside
********************
Subcatchment Summary
Name
Oceanside
Area
INTENSITY 60 min.

Width %Impery %Slope Rain Gage
Outlet
POST_DMA-1
IMP -1
POST_DMA-3
IMP -3
POST_DMA-2
POST_DMA-4
*******************
LID Control Summary
*******************

0.14 0.00

0.11 0.01

0.09 0.09
Subcatchment LID Control
156.00

10.00 98.00

10.00 67.00
243.00
No. of
Units

21.60 0.00

59.80 0.00

23.70 0.00
Unit
Area

2.5000 Oceanside

0.0000 Oceanside

2.5000 Oceanside

0.0000 Oceanside

9.0000 Oceanside

33.0000 Oceanside
Unit
Width
% Area
Covered
IMP -1
POC-1
IMP -3
POC-1
POC-1
POC-1
% Impery % Pery
Treated Treated
IMP -1
IMP -3
************
Node Summary
************
Name
IMP -1
IMP -3
Type
1 121.00
1 217.80
Invert
Elev.

Max.

Depth

0.00 0.00
100.00
100.00
Ponded External
Area Inflow
POC-1

OUTFALL

0.00 0.00 0.0
100.00 0.00
100.00 0.00
38 08/11/2026
PH2 639 of 876

********************************************************* NOTE: The summary statistics displayed in this report are based on results found at every computational time step, not just on results from each reporting time step.
****************
Analysis Options
****************
Flow Units CFS
Process Models:

Rainfall/Runoff YES

RDII NO
Snowmelt NO
Groundwater NO
Flow Routing NO
Water Quality NO
Infiltration Method GREEN_AMPT
Starting Date 08/28/1951 05:08:00
Ending Date 05/23/2008 23:00:00
Antecedent Dry Days 0.0
Report Time Step 01:00:00
Wet Time Step 00:15:00
Dry Time Step 04:@0:00
*****************,,_.- Volume Depth
Runoff Quantity Continuity acre-feet inches
********************,.:rr.x..

Initial LID Storage 0.002 0.043
Total Precipitation 24.507 674.850
Evaporation Loss 2.116 58.266
Infiltration Loss 13.330 367.070
Surface Runoff 3.841 105.764
LID Drainage 5.520 152.018
Final Storage 0.002 0.063
Continuity Error (%) -1.228
Flow Routing Continuity
**************************
Volume Volume
acre-feet 10'6 gal
Dry Weather Inflow 0.000 0.000
Wet Weather Inflow 9.361 3.051
Groundwater Inflow 0.000 0.000
RDII Inflow 0.000 0.000
External Inflow 0.000 0.000
External Outflow 9.361 3.051
Flooding Loss 0.000 0.000
Evaporation Loss 0.000 0.000
Exfiltration Loss 0.000 0.000
Initial Stored Volume 0.000 0.000
Final Stored Volume 0.000 0.000
Continuity Error (%) 0.000
39 08/11/2026
PH2 640 of 876

Eybcatchment Runoff Summary'
N
O
N
Cubcatchment
Total Total Total Total Impery Pery Total Total Peak Runoff Precip Runon Evap Infil Runoff Runoff Runoff Runoff Runoff Coeff in in in in in in in 10^6 gal CFS
POST_DMA-1
IMP -1
POST_DMA-3
IMP -3
POST_DMA-2
POST_DMA-4
LID Performance Summary
xx*** **** ****** **i¢"x**
V
2 N
674.85
674.85
674.85
674.85
674. 85
674.85
Subcatchment LID Co ntrol

0.00 13509 .97

0.00 9230.11
0 .00

0.00 39 .52
1049.77

68.73 1067 .46

23.60 23.40
369 .16

0.00 188.86
0 .00
507.46
463.91
127.45

0.00 351.25

0.00 139 .92

0.00 146.48

0.00 76.07

0.00 8 .08
199.50
273.93
13134.32
427.32
8836.87
148 .00
199.50
1 .02 0.16 0.406

0.99 0.16 0.926

1.25 0.13 0.633
1 .20 0.13 0.892

0.38 0 .09 0.219

0.48 0.10 0.296
To tal Evap Infil Surface Drain Initial Final C ontinuity Inflo w Loss Lass Outflo w Outflo w St orage Storage E rr or in in in in in in in %
IMP -1
IMP -3
IMP -1
IMP -3
14184.82
9904.96
Analysis begun on: Tue Mar 4 08:53:50 2025
,nalysis ended on: Tue Mar 4 08:54:05 2025
-otal elapsed tim e: 00:00:15
918 4° L-179
1049. 82
1067.50

0.00 0.00
3571.82
900 .35
9563 .09
7936 .84
2 .40
2 .40
2 .88 -0 .00
2 .93 -0 .00
40 N
V
0 a
08/11/2026
PH2 642 of 876

9Z0Z/ I. 1. /80
I
912 4 £179
4-
u
3 0
LL

1.000

0.900

0.800

0.700

0.600

0.500

0.400

0.300

0.200

0.100
Flow Duration Curve
[Pre vs . Post (Mitigated)]
- Pre-project Q
- Post -project (Mitigated) 0

0.000

0.0%

0.0% 0.0%
% Time Exceeding

0.1% 1 .0%

Q2 to Q10 Comparison Table- POC-2
Return Period
Existing Condition (cfs)
Mitigated Condition
(cfs)
Reduction, Exist -
Mitigated (cfs)
2 -year

0.530

0.282

0.248
3 -year

0.572

0.333

0.239
4 -year

0.654

0.372

0.282
5 -year

0.675

0.454

0.221
6 -year

0.691

0.491

0.200
7 -year

0.730

0.565

0.165
8 -year

0.748

0.676

0.072
9 -year

0.805

0.741

0.065
10 -year

0.863

0.774

0.088
43 08/11/2026
PH2 644 of 876

Lower Flow
Threshold:
10%

0.1xO2 (Pre):

0.053
cfs
O10 (Pre):

0.8629
cfs
# of Ordinates:
gg
Incremental Q (pre)

0.0082
cfs
Total Houly Data:
499320
hours
Interval
Pre -project
Flow (cfs)
Pre -Project
Hours
Pre -project %
Time Exceeding
Post -Project
Hours
Post -project %
Time Exceeding
Percentage
Pass?Fail
1 0.053
900

0.2%
794

0.16%
88 pass
2 0.061
791

0.2%
606

0.12%
77 pass
3 0.069
791

0.2%
606

0.12%
77 pass
4 0.078
716

0.1%
479

0.10%
67 pass
5 0.086
663

0.1%
393

0.08%
59 pass
6 0.094
613

0.1%
339

0.07%
55 pass
7 0.102
576

0.1%
274

0.05%
48 pass
8 0.110
535

0.1%
238

0.05%
44 pass
9 0.118
535

0.1%
238

0.05%
44 pass
10 0.127
488

0.1%
207

0.04%
42 pass
11 0.135
446

0.1%
186

0.04%
42 pass
12 0.143
413

0.1%
167

0.03%
40 pass
13 0.151
375

0.1%
145

0.03%
39 pass
14 0.159
375

0.1%
145

0.03%
39 pass
15 0.168
332

0.1%
122

0.02%
37 pass
16 0.176
309

0.1%
106

0.02%
34 pass
17 0.184
292

0.1%
97 0.02%
33 pass
18 0.192
276

0.1%
79 0.02%
29 pass
19 0.200
257

0.1%
68 0.01%
26 pass
20 0.208
257

0.1%
68 0.01%
26 pass
21 0.217
240

0.0%
58 0.01%
24 pass
22 0.225
223

0.0%
52 0.01%
23 pass
23 0.233
208

0.0%
47 0.01%
23 pass
24 0.241
189

0.0%
44 0.01%
23 pass
25 0.249
189

0.0%
44 0.01%
23 pass
26 0.258
168

0.0%
40 0.01%
24 pass
27 0.266
149

0.0%
38 0.01%
26 pass
28 0.274
134

0.0%
38 0.01%
28 pass
29 0.282
125

0.0%
33 0.01%
26 pass
44 08/11/2026
PH2
645 of 876

30 0.290
121

0.0%
30 0.01%
25 pass
31 0.298
121

0.0%
30 0.01%
25 pass
32 0.307
118

0.0%
29 0.01%
25 pass
33 0.315
112

0.0%
28 0.01%
25 pass
34 0.323
107

0.0%
26 0.01%
24 pass
35 0.331
97 0.0%
20 0.00%
21 pass
36 0.339
97 0.0%
20 0.00%
21 pass
37 0.347
88 0.0%
19 0.00%
22 pass
38 0.356
80 0.0%
18 0.00%
23 pass
39 0.364
72 0.0%
18 0.00%
25 pass
40 0.372
67 0.0%
17 0.00%
25 pass
41 0.380
65 0.0%
16 0.00%
25 pass
42 0.388
65 0.0%
16 0.00%
25 pass
43 0.397
62 0.0%
16 0.00%
26 pass
44 0.405
60 0.0%
16 0.00%
27 pass
45 0.413
54 0.0%
16 0.00%
30 pass
46 0.421
50 0.0%
16 0.00%
32 pass
47 0.429
50 0.0%
16 0.00%
32 pass
48 0.437
48 0.0%
15 0.00%
31 pass
49 0.446
45 0.0%
14 0.00%
31 pass
50 0.454
43 0.0%
13 0.00%
30 pass
51 0.462
41 0.0%
11 0.00%
27 pass
52 0.470
41 0.0%
11 0.00%
27 pass
53 0.478
41 0.0%
11 0.00%
27 pass
54 0.487
40 0.0%
11 0.00%
28 pass
55 0.495
39 0.0%
11 0.00%
28 pass
56 0.503
37 0.0%
11 0.00%
30 pass
57 0.511
35 0.0%
11 0.00%
31 pass
58 0.519
35 0.0%
11 0.00%
31 pass
59 0.527
33 0.0%
11 0.00%
33 pass
60 0.536
32 0.0%
11 0.00%
34 pass
61 0.544
31 0.0%
11 0.00%
35 pass
62 0.552
29 0.0%
10 0.00%
34 pass
63 0.560
22 0.0%
9 0.00%
41 pass
64 0.568
22 0.0%
9 0.00%
41 pass
65 0.577
22 0.0%
8 0.00%
36 pass
66 0.585
21 0.0%
8 0.00%
38 pass
67 0.593
21 0.0%
8 0.00%
38 pass
68 0.601
21 0.0%
8 0.00%
38 pass
45 08/11/2026
PH2
646 of 876

69 0.609
21 0.0%
8 0.00%
38 pass
70 0.617
21 0.0%
8 0.00%
38 pass
71 0.626
21 0.0%
8 0.00%
38 pass
72 0.634
20 0.0%
8 0.00%
40 pass
73 0.642
18 0.0%
8 0.00%
44 pass
74 0.650
15 0.0%
8 0.00%
53 pass
75 0.658
15 0.0%
8 0.00%
53 pass
76 0.667
13 0.0%
8 0.00%
62 pass
77 0.675
11 0.0%
8 0.00%
73 pass
78 0.683
9 0.0%
8 0.00%
89 pass
79 0.691
9 0.0%
8 0.00%
89 pass
80 0.699
9 0.0%
8 0.00%
89 pass
81 0.707
9 0.0%
8 0.00%
89 pass
82 0.716
9 0.0%
8 0.00%
89 pass
83 0.724
8 0.0%
7 0.00%
88 pass
84 0.732
7 0.0%
6 0.00%
86 pass
85 0.740
7 0.0%
6 0.00%
86 pass
86 0.748
7 0.0%
6 0.00%
86 pass
87 0.757
6 0.0%
6 0.00%
100
pass
88 0.765
6 0.0%
5 0.00%
83 pass
89 0.773
6 0.0%
5 0.00%
83 pass
90 0.781
6 0.0%
5 0.00%
83 pass
91 0.789
6 0.0%
5 0.00%
83 pass
92 0.797
6 0.0%
5 0.00%
83 pass
93 0.806
6 0.0%
5 0.00%
83 pass
94 0.814
6 0.0%
5 0.00%
83 pass
95 0.822
6 0.0%
5 0.00%
83 pass
96 0.830
6 0.0%
4 0.00%
67 pass
97 0.838
6 0.0%
4 0.00%
67 pass
98 0.847
6 0.0%
4 0.00%
67 pass
99 0.855
5 0.0%
4 0.00%
80 pass
100

0.863
5 0.0%
4 0.00%
80 pass
46 08/11/2026
PH2 647 of 876

SWMM Input Data in Input Format
(Existing & Proposed Models)
47 08/11/2026
PH2 648 of 876

PRE-DEV INPUT (POC-2)
[TITLE]
;;Project Title/Notes
[OPTIONS]
;;Option Value

FLOW UNITS CFS
INFILTRATION GREEN_AMPT
FLOW_ROUTING KINWAVE
LINK_OFFSETS DEPTH
MIN_SLOPE 0
ALLOW_PONDING NO
SKIP_STEADY_STATE NO
START_DATE 08/28/1951
START_TIME 05:08:00
REPORT_START_DATE 08/28/1951
REPORT_START_TIME 05:00:00
END_DATE 05/23/2008
END_TIME 23:00:00
SWEEP_START 01/01
SWEEP_END 12/31
DRY_DAYS 0
REPORT_STEP 01:00:00
WET_STEP 00:15:00
DRY_STEP 04:00:00
ROUTING_STEP 0:01:00
RULE_STEP 00:00:00
INERTIAL_DAMPING PARTIAL
NORMAL_FLOW_LIMITED BOTH
FORCE_MAIN_EQUATION H -W
VARIABLE_STEP 0.75
LENGTHENING_ STEP 0
MIN_SURFAREA 12.557
MAX_TRIALS 8
HEAD_TOLERANCE 0.005
SYS_FLOW_TOL 5
LAT_FLOW_TOL 5
MINIMUM_STEP 0.5

THREADS I
48 08/11/2026
PH2 649 of 876

[EVAPORATION]
;;Data Source Parameters
;;
MONTHLY 0.06 0.08 0.110 0.15 0.17 0.19 0,19 0..18 0.15 0.11 0.08 0.06 DRY_ONLY NO
[RAINGAGES]
;;Name
;;
Oceanside
Format Interval SCF Source
[SUBCATCI LENTS]
;;Name
;;
Basins_6
INTENSITY 1:00
Rain Gage

1.0 TIMESERIES Oceanside
Outlet
Area %Impery Width %Slope CurbLen SnoNPack
Oceanside POC-2

0.99 8 375 7.5 0
[SUBAREAS]
;;Subcatchment N-Irpery N-Pery S-Irrpery S-Pery PctZero RouteTo PctRouted ;;
Basins_6 0.012 0.15 0.05 0.1 25 OUTLET
[INFILTRATION]
;;Subcatchment Paraml Param2 Param3 Param4 Param5
;;
Basins_6 9 0.025 0.30 7 0
[OUTFALLS]
;;Name
;;
POC-2 0 FREE NO
Elevation Type Stage Data Gated Route To
[TIMESERIES]
;;Name Date Time Value
;;
Oceanside FILE "Z:\Projects\2023\23-221,PROD'\.Reports\WQMP\SWMM\oceanside,dat" 49 08/11/2026
PH2 650 of 876

[REPORT]
;;Reporting Options

SUBCATCHMENTS ALL

NODES ALL

LINKS ALL
[TAGS]
[MAP]
DIMENSIONS -966.709 0.000 10966.709 10000.000
Units None
[COORDINATES]
;;Node
;;
POC-2 -380.739 582.919
X-Coord Y-Coord
[VERTICES]
;Link
;;
X-Coord Y-Coord
[Polygons]
;Subcatchment X-Coord Y-Coord
;;
Basins_6
Basins_6
Basins_6
Basins_6
[SYMBOLS]
;;Gage
;;
Oceanside -455.102 623.163
- 494.717
- 442.956
- 439.819
- 494.717
551.400
551.400
598.455
600.024
X-Coord Y-Coord
50 08/11/2026
PH2 651 of 876

POST-DEV INPUT (POC-2)
[TITLE]
;;Project Title/Notes
[OPTIONS]
;;Option Value
FLOW_UNITS CFS
INFILTRATION GREEN_AMPT
FLOW_ROUTING KINWAVE
LINK_OFFSETS DEPTH
MIN_SLOPE 0
ALLOW_PONDING NO
SKIP_STEADY_STATE NO
START_DATE 08/28/1951
START_TIME 05:00:00
REPORT_START_DATE 08/28/1951
REPORT_START_TIME 05:00:00
END_DATE 05/23/2008
END_TIME 23:00:00
SWEEP_START 01/01
SWEEP_END 12/31
DRY_DAYS 0
REPORT_STEP 01:08:00
WET_STEP 00:15:00
DRY_STEP 04:00:00
ROUTING_STEP 0:01:00
RULE_STEP 00:08:08
INERTIAL_DAMPING PARTIAL
NORMAL_FLOW_LIMITED BOTH
FORCE_MAIN_EQUATION H -W
VARIABLE_STEP 0.75
LENGTHENING_STEP 0
MIN_SURFAREA 12.566
MAX_TRIALS 8
HEAD_TOLERANCE 0.005
SYS_FLOW_TOL 5
LAT_FLOW_TOL 5
MINIMUM_STEP 0.5
THREADS 4
51 08/11/2026
PH2 652 of 876

[EVAPORATION]
;;Data Source Parameters
;;

MONTHLY
DRY_ONLY
.06 .08 .11 .15 .17 .19 .19 .18 .15 .11 .08 .06
NO
[RAINGAGES]
;;Name Format Interval SCF Source
;;
Oceanside INTENSITY 1,00 1.0 TIMESERIES Oceanside
[SUBCATCHMENTS]
;;Name
;;
POST_DMA-5 Oceanside IMP -4 0.257 86.4 255 3.5 0
IMP -4 Oceanside POC-2 0.00730028 0 10 0 0
POST_DMA-B Oceanside POC-2 0.03 0 90 48 0
POST_DMA-6 Oceanside IMP -5 0.162 36.3 158 3.5 0
POST_DMA-7 Oceanside IMP -6 0.744 73 635 3.5 0
IMP -5 Oceanside ROC -2 0.003214 0 10 8 0
IMP -6 Oceanside DIV 0.032139 0 10 0 0
Rain Gage
Outlet
Area %Impery Width %Slope CurbLen SnowPack
[SUBAREAS]
;;Subcatchment N-Impery N-Pery S-Impery S-Pery Pctlero RouteTo PctRouted ;;
POST_DMA-5 0.012 0.15 0.05 0.1 25 OUTLET
IMP -4 0.012 0.15 0.05 0.1 25 OUTLET
POST_DMA-B 0.012 0.15 0.05 0.1 25 OUTLET
POST_DMA-6 0.012 0.15 0.05 0.1 25 OUTLET
POST_DMA-7 0.012 0.15 0.05 0.1 25 OUTLET
IMP -5 0.012 0.15 0.05 0.1 25 OUTLET
IMP -6 0.012 0.15 0.05 0.1 25 OUTLET
[INFILTRATION]
;;Subcatchment Paraml Param2 Param3 Param4 Param5
;;
POST_DMA-5 9 0.01875 0.3 7 0
IMP -4 1.5 0.3 0.33 7 0
POST_DMA-8 1.5 0.3 0.33 7 0
POST_DMA-6 9 0.01875 0.3 7 0
POST_DMA-7 9 0,01875 0.3 7 0
IMP -5 1.5 0.3 0.33 7 0
IMP -6 1.5 0.3 0.33 7 0
[LID_CONTROLS]
;;Name Type/Layer Parameters
;;
IMP -4 BC
IMP -4 SURFACE 10 0.0 8 0 5
IMP -4 SOIL 24 0.4 0.2 0.1 5 5 1.5
IMP -4 STORAGE 15 0.67 0 0
IMP -4 DRAIN 0.0714 0.5 3 6 0 =
IMP -5
IMP -5
IMP -5
IMP -5
IMP -5
IMP -6
IMP -6
IMP -6
IMP -6
IMP -6
BC
SURFACE 10 0.0 0 0 5
SOIL 24 0.4 0.2 0.1 5
STORAGE 15 0.67 0 0
DRAIN 0.1499 0.5 3 6 0
BC
SURFACE 10 0.0 0 0 5
SOIL 24 0.4 0.2 0.1 5 -
STORAGE 30 0.9 0 0
DRAIN 0.1535 0.5 0 6 0 1

1.5 52
08/11/2026
PH2 653 of 876

9Z0Z/ L L/80
2 IV
919 4° 1759
[LID_USAGE]
;;Su bcatchment
;;
IMP -4
IMP -5
IMP -6
LID P roc ess
Number Area Width InitSat FromImp ToPery RptFile
Drai nTo FromP ery
IMP -4
IMP -5
IMP -6
1 318.66 0 8 100 0 *
1 140.00 0 6 100 0
1 1399 .97 0 8 100 0
[OUTFALLS]
;;Na me Ele vation Type St age D ata Gated R oute To
;;
POC-2 0 FREE NO
[DIVIDERS]
;;Nam e Elevation Diverted Link Type Parameters
;;
DIV 8 Bypass CUTOFF 0.19 0 6 0 6
POC-2
ROC -2
POC-2
[STORAGE]
;;Name Elev, Max Depth InitDepth Shape Curve Name/Params N/A Fevap Psi Ksat IMO ;;
AQ 0 5 0 TABULAR Sto rage 1800 6
[CONDUITS]
;;Name Fro m Node To Node Length Roughness InOffset OutOffset InitFlow MaxFlow ;;
Bypass DIV AQ 460 6.61 0 0 0 0
Underdrain DIV ROC -2 20 0.01 0 0 0 S
[OUTLETS]
;;Na me From Node To Node Offset Type QTabl e/Qcoeff Qexpon Gated ;;
Outlet AQ POC-2 0 FUNCTIONAL/DEPTH 16.6 0.5 NO
[XSECTIONS]
;;Link Shape Geoml Geom2 Geom3 Geom4 Barrels Culvert
;;
Bypass DUMMY 0 0 0 6 1
Underdrain CIRCULAR 0.5 6 0 0 1
53 0
9 [CURVES]
;;Marne Type X -Value Y -Value
Outletcurve Rating 1 0.0176
Outletcurve 2 0.0481
Outletcurve 3 0.0850
Outletcurve 4 0.1097
Outletcurve 5 0.1298
Outletcurve 6 0.1471
Outletcurve 7 0.1627
Outletcurve 8 0.1769
Outletcurve 9 0.1900
Outletcurve 10 0.2022
Outletcurve 11 0.2138
Outletcurve 12 0.2248
Outletcurve 13 0.2352
Outletcurve 14 0.2452
Outletcurve 15 0.2549
Outletcurve 16 0.2641
Outletcurve 17 0.2731
Outletcurve 18 0.2818
Outletcurve 19 0.2902
Outletcurve 20 0.2984
Outletcurve 21 0.3863
Outletcurve 22 0.3141
Outletcurve 23 0.3216
Outletcurve 24 0.3290
Outletcurve 25 0.3363
Outletcurve 26 0.3433
Outletcurve 27 0.3503
Outletcurve 28 0.3571
Outletcurve 29 0.3638
Outletcurve 30 0.3703
Outletcurve 31 0.3768
Outletcurve 32 0.3831
Outletcurve 33 0.3893
Outletcurve 34 0.3955
Outletcurve 35 0.4015
Outletcurve 36 0.4074
Outletcurve 37 0.4133
Outletcurve 38 0.4191
Outletcurve 39 0.4248
Outletcurve 40 0.4304
Outletcurve 41 0.4360
Outletcurve 42 0.4414
Outletcurve 43 0.4469
Outletcurve 44 0.4522
Outletcurve 45 0.4575
Outletcurve 46 0.4627
Outletcurve 47 0.4679
Outletcurve 48 0.4730
Outletcurve 49 0.4781
Outletcurve 50 0.4831
Outletcurve 51 0.4880
Outletcurve 52 0.4929
Outletcurve 53 0.4978
Outletcurve 54 0.5026
Outletcurve 55 0.5074
Outletcurve 56 0.5121
Outletcurve 57 0.5168
Outletcurve 58 8.5214
Outletcurve 59 0.5260
Outletcurve 60 0.5306
54 08/11/2026
PH2 655 of 876

9Z0Z/ L 1. /80
Stor age St orage 0 5
Storage 2.5 5
Storage 2.501 5
Storage 4.5 5
Storage 4.501 5
Sto rage 5.33 5
[TIMESERIES]
;;Name
Date
Time Value
Oceanside
\oceanside.dat"
FILE "C:\Users\ massy..fatini\DC\ACCDocs\SWS Engineering\2023\Project Files\23-299\PROD'Reports\WQMP\SWMM\oceanside Raingauge [REPORT]
;;Reporting Options

INPUT YES
SUBCATCI1MENTS ALL

NODES ALL
'_INKS ALL
lj [TAGS]
N [MAP]
DIMENSIONS -129.191 -319. 762 933.945 189.693
Units Feet
918 40 999
55 [COORDINATES]
;;Node
;;
POC-2
DIV
AQ
[VERTICES]
;;Link
;;
X-Coord Y-Coord
302.477
296.581
209.227
-217.043
-145.918
- 185.390
X-Coord Y-Coord
[Polygons]
;;Subcatchment X-Coord Y-Coord
;;
POST_DMA-5
POST_DMA- 5
POST_DMA-5
POST_DMA-5
IMP -4
IMP -4
IMP -4
IMP -4
IMP -4
POST_DMA-8
POST_DMA-8
POST_DMA-8
POST DMA -8
POST_DMA-6
POST _DMnA - 6
POST_DMA-6
POST_DMA-6
POST_DMA-7
POST_DMA-7
POST_DMA-7
POS T_DMA - 7
IMP -5
IMP -5
IMP -5
IMP -5
IMP -6
IMP -6
IMP -6
IMP -6
[SYMBOLS]
;;Gage
;;
Oceanside
661.816
663.684
567.827
564.715
585.116
628.065
631.800
584.494
584.494
568.161
568.975
473.660
473.660
485.781
487.631
404.998
406.231
315.581
324.831
241.581
239.114
473.448
473.911
427.660
425.194
322.364
323.598
270.564
266.247

89.765

22.540
20,.051

87.275
-65.175
- 65.175
- [email protected]
-105.011
- 76.379
-248.964
- 305.990
- 306.805
-247.334

81.733

24.382

21.299

82.349

72.483

16.366

13.899

70.016
- 71.355
-110.360
- 111.593
-75.826
-80.760
- 117.143
-118.993
- 85.076
X-Coord Y-Coord
262.393 152.341
56 08/11/2026
PH2 657 of 876

PRE -DEVELOPMENT CONDITION (POC-2)
Oceanside
El
POC-2
57 08/11/2026
PH2 658 of 876

Outfall POC-2
Rain Gage Oceanside
Property I Value
Name
X -Coordinate
Y -C ccrdinate
Description
Oceanside
-461.401
627.712
Property I Value
Name
Tag.

Rain Format

INTENSITY
Time Interval
Snow Catch Factor
1:00
Data Source
TIME SERIES:
- Series Name
DATA FILE:
- File Name
- Station ID
- Rain Units
IN

1.0 Ti MESERIES
Oceanside
X -Coordinate
Y -Coordinate
Description
Tag
Inflows
POC-2
-371.816
587.643
NO
Treatment
NO
Invert El.

Tide Gate
0 NO
Route To
Type
Fixed Outfall
Fixed Stage
Tidal Outfall
Curve Name
Time Series. Outfall
Series Name
FREE
58 08/11/2026
PH2 659 of 876

Subcatchment Basins_6
Property
Value
Name
sBasins_6
X -Coordinate
-468.052
Y -Coordinate
575.320
Description
Tag
Rain Gage
Oceanside
Outlet
POC-2
Area

0.99 Width
375
% Slope

7.5 % Impery
0 N-Impery

0.012
N -Pew

0.15 Dstore-lmpery

0.05 Dstore-Pery

0.1 %Zero-Impery
25 Subarea Routing
OUTLET
Percent Routed
100
Infiltration Data
GREEN_AMPT
Groundwater
NO
Snow Pack
LID Controls
0 Land Uses
0 Initial Buildup
NONE
Curb Length
0 N -Pew Pattern
Dstore Pattern
Infil, Pattern
Infiltration Editor X
Infiltration Method
GREEN_AMPT .,
Property
Value
Suction Head
D.025
Conductivity
Initial Deficit
D.30
Soil capillary suction head (inches or mm)
59 08/11/2026
PH2
660 of 876

POST -DEVELOPMENT CONDITION (POC-2)
Oceanside
60 08/11/2026
PH2
661 of 876

Rain Gage Oceanside
Property
Value
Name
Oceanside
X -Coordinate
.245.127
V -Coordinate
147.408
Description
Tag
Rain Format

INTENSITY
Time Interval
1:00
Snow Catch Factor

1.0 Data Source
T1h41ESERIES
TIME SERIES:
- Series Name
Oceanside

DATA FILE
- File Name
- Station ID
- Rain Units
IN
Outfall POC-2
x
Property
Value
Name
POC-2
285210
X- Coordinate
V -Coordinate
-232.460
Description
Tag
Inflows
NO
Treatment
NO
Invert EL
0 Tide Gate
NO
Route To
Type
Fixed Outfall
FREE
Fixed Stage
Tidal Outfall
Curve Name
Time Series Outfall
I
Series Name
61 08/11/2026
PH2 662 of 876

Subcatchment POST DMA -5
P ro p erty
Larne
Value
POST DMA -5
X -Coordinate
514.511
Y -Coordinate

54.908
Description
Tag
Rain Gage
Oceanside
Outlet
IMP -4
• Area
0257
Width
255
%Slope
3,5
% Impel,/

86.4 N-Irnpery
0,012
N-Pery
0,15
Dstore-Impery

0.05 Dstore-Dery

0.1 %Zero-Impery
25 Subarea Routing OUTLET
Percent Routed 100
Infiltration Data
GREEN_AMPT
'Groundwater
NO
Snow Pack
LID Controls
0 Land Uses
O
Initial Buildup
NONE
Curb Length
0 N-Pery Pattern
Dstore Pattern
Infil, Pattern
Infiltration Editor X
Infiltration Method
GREEN_AMPT
Property
Value
Suction Head
9 0.01875
Conductivity
Initial Deficit

0.3 Soil capillary suction head (inches or mm)
62 08/11/2026
PH2 663 of 876

Subcatchment IMP -4 x
Property
-
Value
Name
...-
!IMP -4
602.794
X -Coordinate
Y -Coordinate
-83.226
Description
Tag
Rain Gage
Oceanside
Outlet
POC-2
Area

0.00730028
Width
10 %Slope
0 % lmpery
0 N- l rnpery

0.012
N-Pery

0.15 Dstore-Impery

0.05 Dstore-Penn

0.1 %Zero-Irrmpery
25 Subarea Routing
OUTLET
Percent Routed
100
Infiltration Data
GREEN_AMPT
Groundwater
NO
Snow Pack
LID Controls
1 Land Uses
0 Initial Buildup
NONE
Curb Length
0 N-Pery Pattern
Dstore Pattern
Infil. Pattern
Infiltration Editor X
Infiltration Method
GREEN_AMPT
Property
Value
Suction Head
1,5
03 Conductivity
Initial Deficit
0 33
Soil capillary suction head (inches or mm)
63 08/11/2026
PH2 664 of 876

LID Usage Editor
LID Control Name
imp -4
Detailed Report File (Optional)
❑ LID Occupies Full Subcatchment
Area of Each Unit (sq ft or sq m)
Number of Units
% of Subcatchment Occupied
Surface Width per Unit (ft or m)
% Initially Saturated
of Impervious Area Treated
% of Pervious Area Treated
318.00
1 100.0
0 0
100
0 Send Drain Flow To:
(Leave blank to use subcatchment outlet)
POC-2
El Return all Outflovy to Pervious Area
OK
Cancel Help
64 08/11/2026
PH2 665 of 876

9Z0Z/ I. 1. /80
91840 999
LID Control Editor
Control Name:

LID Type:
f
BEE
Bio-Rete nti on C ell
1urface
Sto ra_=e
*Optional
f
Efrain'
OK Cancel Help
Surface S oil
Storage Drain
Berm Height
(in. or mm)
Vegetati on V ol ume
Fracti on
Surface R oughness
(Mannings n)
Surface Sl ope
(percent)
10 0.0
0 0
LID Co ntro l Edito r
Con tro l Name:

LID Type:

IMP -4
Bio-Retention Cell
Soil
Storage
`Option al
Drain "
OK Cancel Help
Surface Soil
Thickness
(in. or mm)
Sto rage Drain
Vo id Ratio
(Voids / Solids)
Seepage Rate
(in/hr or mm/hr)
Cloggin g Factor
X
15 0. 67
0 0
LID C ontrol Editor
Contr ol Nam e:

LID Type:

I MP -4
Bio-Retenti on Cell
.Surfac e
Soil
Storage
r OK
*Optional
Cancel
Drain`
Help
Surface Soil Storage Drain
Thickness
(in. or mm)
Porosity
( volume fracti on)
Field Capacity
( volume fraction)
Wilting P oint
( volume fra cti on)
Conducti vity
(in/hr or mm/hr)
C onducti vity
Slope
S ucti on Head
(in. or mm)
24 0.4
0 .2

0.1 5
5 1 .5
X
LID Contr ol Edit or
Contr ol Name:

LID Type:

OK
IMP -4
Bi o-Retention Cell
'Optio nal
Cancel I
Drai n'
Surface Soil
Storage Drain
Fl ow C oefficient *
Flow Exp onent
Offset (in or mm)
Open Le vel (in or mm)
Closed Level (in or mm)
Control Curve

0.0714

0.5 3
0 0
w
Drain Advisor
*Fl ow is in in/hr or mm/hr, use 0 if
there is no drain.

X
65 Subcatchment POST DMA -6
Property
Value
Name
X -Coordinate
Y -Coordinate
Description
Tag
POST DMA -6
446.160

52.441
Rain Gage Oceanside
Outlet
Area
Width
% Slope
% Impery
N- I mpery
N -Peru
Dstore-I mpery
Dstore-P ery
%Zero-Impenr
Subarea Routing
Percent Routed
Infiltration Data
Groundwater
Snow Pack
LID Controls
Land Uses
Initial Buildup
Curb Length
N -Peru Pattern
Dstore Pattern
Infil, Pattern
IMP -5

0.162
158

3.5 36.3

0.012

0.15 0.05

0.1 as
OUTLET
100

GREEN AMPT
NO
0 0
NONE
Infiltration Editor
Infiltration Method
X
GREEN_AMPT
Property
Value
Suction Head
9 Conductivity

0.01875
Initial Deficit
0,3
Soil capillary suction head (inches or mm)
66 08/11/2026
PH2 667 of 876

Subcatchment IMP -5
Property Value
Name
IMP -5
i-Coordinate
450.053
V -Coordinate
-92.284
Description
Tag
Rain Gage
Oceanside
Outlet
POC-2
Area

0.003214
Width
10 % Slope
0 % Impery
0 r'J -1 mpery

0.012
N -Peru

0.15 Dstore-lrnpery

0.05 Dstore-Pery

0.1 %Zero-Imperr
25 Subarea Routing
OUTLET
Percent Routed
100
Infiltration Data ,GREEN_AMPT
Groundwater
NO
Snow Pack
LID Controls
;1
I0
Land Uses
Initial Buildup
NONE
Curb Length
I0
N-Pery Pattern
Dstore Pattern
Infil, Pattern
Infiltration Editor X
Infiltration Method
GREEN_AMPT
Property
Value
Suction Head
-I,y

0.3 _.

Conductivity
Initial Deficit
0„13
Soil capillary suction head (inches or mm)
67 08/11/2026
PH2 668 of 876

LID Wage Editor
X
LID Control Name
Detailed Report File (Optional)
LX.,
❑ LID Occupies Full Subcatchment
Area of Each Unit (sq ft or sq m)
Number of Units
a% of Subcatchment Occupied
Surface Width per Unit (ft or m)
% Initially Saturated
% of Impervious Area Treated
% of Pervious Area Treated
140.00
1 100.0
0 0
100
0 Send Drain Flow To;
(Leave blank to use subcatchment outlet)
POC-2
❑ Return all Outflow to Pervious Area
OK
Cancel
Help
68 08/11/2026
PH2 669 of 876

9Z0Z/ I. 1. /80
919 40 0L9
LID C ontrol Editor
Control Nam e:

LID Type:
*Optional
LID Control Editor
Control Name
LID Type
TEE
Bi o-Rete nti on Cell
Surface
Drain'
LEIE
Bio-Retentio n Cell
��Su rfac=
Soil
r
Stora ge
*Optio nal
Drain '
Help
Surface S oil St orage Drai n
Berm Height
(in. or mm)
Vegetation Volume
Fraction
Surface R oughness
( Mannings n)
Surface Slope
(percent)
10 0 .0
0 0
Surface So il
Thickness
(in. or mm)
Storage Drain
Void Ratio
(Voids ! Solids)
Seepage Rate
On/hr or mm/hr)
Clo gging Facto r
33 0. 67
0 0
X
LID C ontrol Editor
C ontrol Name:

LID Type:
*Opti onal
OK
Bio-Retenti on Cell
Cancel
Help
Surface S oil Storag e Drai n
Thickness
(in. or mm)
P or osity
( volume fracti on)
Field Capacity
( volume fraction)
Wilting Point
( volume fracti on)
Conducti vity
(in/hr or mm/hr)
Conducti vity
Slope
Sucti on Head
(in. or mm)
24 0.4
02 0.1
5 5
1 .5
X
LID C ontrol Edit or
Contr ol Name
LID Type
Bio-Rete nti on C ell
"iurface
Soil
Stor ag e
OK
* Optional
Cancel
Drain*
Surface Soil Storage Drain
Fl ow C oefficient*
Fl ow Expo nent
Offset (in or mm)
Open Le vel (in or mm)
Closed Level (in or mm)
Contr ol Curve

0.1499
0 .5
3 0
0 NJ
Drain Ad vis or
*Flow is in in.: hr or mm/hr; use 0 if
there is no drain.
69 Subcatchment POST DMA -7
Property
Name
X -Coordinate
`?-Coordinate
, Description
Tag
Rain Gage
Outlet
Area
Width
% Slope
% Impery
N. Impery
N -Peru
Dstore- Imperr
Dstore- P err
Value
P OST DMA -7
280.277

43.191
Oceanside
IMP -6
0 714
635

3.5 73

0.012
%Zero-lmpery
Subarea Routing
Percent Routed
Infiltration Data
Groundwater
Snow Pack
LID Controls
25 OUTLET
100
GREEN_AMPT
NO
j.
€0
Land Uses
Initial Buildup
Curb Length
hJ-Per. Pattern
Dstore Pattern
0 NONE
0 Infil. Pattern
Infiltration Editor
Infiltration Method
X
GREEN_AMPT
Property
Value
Suction Head
Conductivity

0.01875
Initial Deficit
03 Soil capillary suction head (inches or mm)
OK Cancel Help
70 08/11/2026
PH2 671 of 876

Subcatchment IMP -6
x r
Property
Value
Name
IMP -6
X -Coordinate
295.693
lit -Coordinate
-100.493.

Description
Tag
Rain Gage
Oceanside
Outlet
DIV
Area

0.03.2139
Width
10 %Slope
0 % lrnpery
0 N-Impery

0.012
N-Pery

0.15 Dstore-Impery

0.05 Dstore-Pery 0.1
%Zero-Impery 25
Subarea Routing
OUTLET
Percent Routed
Infiltration Data
Groundwater
Snow Pack
LID Ccntrcls
Land Uses
Initial Buildup
Curb Length
N-Pery Pattern
D store Pattern
Infil, Pattern
100
GREEN_AMPT
NO
1 0
NONE
0 Infiltration Editor X
Infiltration Method
GREEN_AMPT ,...-
Property
Value
Suction Head

1.5 Conductivity
0,3
Initial Deficit

0.33 Soil capillary suction head finches or rnm)
OK
i Cancel
I
I Help
71 08/11/2026
PH2 672 of 876

LID Usage Editor
LID Control Name
Detailed Report File (Optional)
❑ LID Occupies Full Subcatchment
Area of Each Unit (sq ft or sq m)
Number of Units
% of Subcatchment Occupied
Surface Width per Unit (ft or m)
% Initially Saturated
% of Impervious Area Treated
% of Pervious Area Treated
1399.97
Send Drain Flow To:
(Leave blank to use subcatchment outlet)
❑ Return all Outflow to Pervious Area
Cancel Help
72 08/11/2026
PH2 673 of 876

9Z0Z/ I. 1. /80
919 40 1719
LID Control Editor X
Control Name:

LID Type :

IMP -6
Bio-Retenti on Cell
urface
Soil
Storage
i
'Optional
OK I Cancel
Drain'
He)
Surfac e Soil Storage Drai n
Berm Height
(in. or mm)
Vegetati on Volume
Fraction
S urface Roughness
(Mannings n)
S urface Sl ope
(percent)
10 0 .0
0 0
LID Control Editor
Contro l Name
LID Type
So il
IMP -6
Bio-Re tentio n Cell
Su rface
Starage
'Optional
OK 1 Cancel 1
Dra in '
Help
Surface Soil
Storage Drain
Thickness
(in. or mm)
Void Ratio
(Vo ids / Solids)
Seepage Rate
(in/hr or mm/hr)
Clo gging Factor
30 0.9
0 0
LID Contr ol Editor
Control Name:

LID Type:

Soil
Bio-Rete nti on Cell
Surface
r
Storag e
OK
"Opti onal
Cancel
Drain'
Help
Surface Soil
St orage Drain
Thickness
(in. or mm)
Porosity
(vol ume fracti on)
Field Capacity
( volume fracti on)
Wilting Point
(volume fracti on)
Conductivity
(in/hr or mm/hr)
C onductivity
Sl ope
Sucti on Head
(in. or mm)
24 0.4
02 0.1
5 5
1 .5
LID Control Editor
C ontrol Name:

LID Type:

Soil
Bi o-R ete ntion Cell
Surface
r
Storag e
`Option al
OK Cancel
Drai n'
Surfac e Sail Storage Drain
Fl ow C oefficient '
Flow Exponent
Offset (i n or mm)
Open Level (in or mm)
Closed Le vel (in or mm)
Control C ur ve

0.1535
0 .5
0 0
0 Drain Advisor
'Flow is in in/hr or mm/hr, use 0 if
there is no drain.
73 Subcatchrnent POST DMA -B
Property
Name
Value
POST DMA -8
X -Coordinate

86.543
Y -Coordinate

37.024
Description
Tag
Rain Gage
Oceanside
Outlet
POC-2
Area

0.03 Width
90 % Slope
48 % I mpery
D
!+t Imperr
0,012
N-Pery

0.15 Dstore-Impery
D,05
Dstore-Pery

0.1 %Zero-Impery
25 Subarea Routing
OUTLET
Percent Routed
100
Infiltration Data
GREEN_AMPT
Groundwater
NO
Snow Pack
LID Controls
Land Uses
0 Initial Buildup
NONE
Curb Length
0 N-Pery Pattern
Dstore Pattern
Infil, Pattern
Infiltration Editor X
Infiltration Method
GREEN_AMPT
Property
Value
Suction Head

1.5 Conductivity

0.3 Initial Deficit

0.33 Soil capillary suction head (inches or mm)
OK
I Cancel
Help —1
74 08/11/2026
PH2
675 of 876

Summary Files from the SWMM Model
75 08/11/2026
PH2 676 of 876

PRE-DEV OUTPUT (POC-2)
EPA STORM WATER MANAGEMENT MODEL - VERSION 5.1 (build 5.1.015) NOTE: The summary statistics displayed in this report are based on results found at every computational time step, not just an results from each reporting time step.
********************************************************* ****************
Analysis Options
****************
Flow Units CFS
Process Models:

Rainfall/Runoff YES

RDII NO
Snowmelt NO
Groundwater NO
Flow Routing NO
Water Quality NO
Infiltration Method GREEN_AMPT
Starting Date 08/28/1951 05:00:08
Ending Date 05/23/2008 23:00:00
Antecedent Dry Days 0.$
Report Time Step 01:00:00
Wet Time Step 00:15:00
Dry Time Step 04:00:00
************************** Volume Depth
Runoff Quantity Continuity acre-feet inches
**************************
Total Precipitation
Evaporation Loss
Infiltration Loss
Surface Runoff
Final Storage
Continuity Error (%)
**************************
Flow Routing Continuity
**************************

55.697 675.110

2.978 25.191

42.325 513.027

12.460 151.032

0.000 0.001
-2.095
Volume Volume
acre-feet 10A6 gal
Dry Weather Inflow 0.000 0.000
Wet Weather Inflow 12.460 4.060
Groundwater Inflow 0.000 0.000
RDII Inflow 0.000 0.000
External Inflow 0.000 0.000
External Outflow 12.460 4.060
Flooding Loss 0.000 0.000
Evaporation Loss 0.000 0.000
Exfiltration Loss 0.000 0.000
Initial Stored Volume .,, 0.000 0.000
Final Stored Volume 0.000 0.000
Continuity Error (%) 0.000
76 08/11/2026
PH2 677 of 876

9Z0Z/ I. 1. /80
919 40 8L9
** ******** ********* ** ** *** *
Subcatchment Runoff Su mmary
** **** ** *********** **** ****
Subcatchment
Total Total Total T otal Impery Pery Total Total Peak Runoff Precip Run on E vap Infi1 Run off Runoff Run off Runoff Runoff Coeff in in in in in in in 18^6 gal CFS
Basins_6 675.11
8 .80 25.19
Analysis begun on: Tue Jan 7 21:39:48 2025
Analysis e nded on : Tue Jan 7 21:40:01 2025
To tal elapsed time: 85:00:13
513.03 8 .88
151.03 151.03

4.06 1.11 8.224
77 POST-DEV OUTPUT (POC-2)
EPA STORM WATER MANAGEMENT MODEL - VERSION 5.1 (build 5.1,015) WARNING 04: minimum elevation drop used for Conduit Bypass WARNING 04: minimum elevation drop used for Conduit Underdrain *************
Element Count
*************
Number of rain gages 1
Number of subcatchments 7
Number of nodes 3
Number of links 3
Number of pollutants 0
Number of land uses 0
****************
Raingage Summary
****************
Name Data Source
Data Recording
Type Interval
Oceanside Oceanside
********************
Subcatchment Summary
********************
Name
INTENSITY 60 min.

Area Width %Impery %Slope Rain Gage Outlet
POST_DMA-5
IMP -4
POST DMA -8
POST_DMA- 6
POST_DMA-7
IMP -5
IMP -6
*******************
LID Control Summary
*******************

0.26 255.00 86.40 3.5000 Oceanside

0.01 10.60 0.00 0.0060 Oceanside

0.03 90.00 0.80 48,0600 Oceanside

0.16 158.00 36,30 3.5000 Oceanside

0.74 635.00 73.00 3.5000 Oceanside

0.00 10.00 8,68 0.6600 Oceanside

0.03 10.00 0,60 0.0660 Oceanside
IMP -4
POC-2
POC-2
IMP -5
IMP -6
POC-2
DIV
No. of Unit Unit % Area % Impery % Pery
Subcatchment LID Control Units Area Width Covered Treated Treated IMP -4
IMP -5
IMP -6
************
Node Summary
************
IMP -4
IMP -5
IMP -6
Name Type
1 318.60 0.00 100.80 100.00 0.00
1 140.08 8.00 188.60 100.00 0.00
1 1399.97 0.00 100,86 180.00 0.00
Invert Max. Ponded External
Elev. Depth Area InfloN
POC-2
DIV
AQ

OUTFALL

DIVIDER

STORAGE

8.80 0.08

0.BB

0.50 8.50

5.08 0,0

0.0 0.0
78 08/11/2026
PH2 679 of 876

Link Summary
************
Name
From Node
To Node Type
Length %Slope Roughness
Bypass DIV
Underdrain DIV
Outlet AQ
*********************
Cross Section Summary
*********************
Conduit Shape
AQ
POC-2
POC-2

CONDUIT

CONDUIT
OUTLET
480.0

20.0 0.8093

0.0050
Full Fu11 Ffyd. Max. No. of Full
Depth Area Rad. Width Barrels Flow
Bypass DUMMY 0.00 0.00 0.00 0.80 i 0.00
Underdrain CIRCULAR 0.50 0.20 0.13 0.50 1 0.05
********************************************************* NOTE: The summary statistics displayed in this report are based on results found at every computational time step, not just on results from each reporting time step.
********************************************************* ****************
Analysis Options
****************
Flow Units .. CFS
Process Models:

Rainfall/Runoff YES

RDII NO
Snowmelt NO
Groundwater NO
Flow Routing YES
Ponding Allowed NO
Water Quality NO
Infiltration Method GREEN_AMPT
Flow Routing Method KINWAVE
Starting Date 08/28/1951 85;00;00
Ending Date 05/23/2008 23:00:00
Antecedent Dry Days . . . 0.8
Report Time Step 01:00:00
Wet Time Step 00:15:00
Dry Time Step 04:00:00
Routing Time Step 60.00 sec
************************** Volume Depth
Runoff Quantity Continuity acre-feet inches
**************************
Initial LID Storage 0.909 0.083
Total Precipitation 69.490 674.850
Evaporation Loss 11.077 107.572
Infiltration Loss 14.868 144.317
Surface Runoff 5.889 57.187
LID Drainage 38.720 376.025
Final Storage 0.014 0.136
Continuity Error (%) -1.527

0.0100
79 08/11/2026
PH2 680 of 876

9Z0Z/ I L/80
912 4° 1,89
*** ******************** *** Volume Volume
Flow Routing Continuity acre-feet 10A6 gal
***** ** ******* ***** *******
Dry Weather Inflo w 0.000 0.000
Wet Weather Inflow 44.608 14.536
6roundv,ater Inflow 0.000 0.000
RDII Inflow 0.000 0.000
Exter nal Inflow 0 .000 0.000
External Outflow 44.143 14.385
Flooding Loss 0.462 0 .150
Evaporation Loss 0.000 0.000
Exfiltration Loss 8.000 8.000
Initial Stared Vo lume 0 .000 0.000
Final Stor ed Volum e 0.000 0.088
Continuity Err or (%) 0.009
****** ***** *** ******** ** ********
Highest Flo w Instability Indexes
*********** ************** *******
All links are stable.
* ***** *** ***** ***** **** **
Routing Time Step Summary
** ****** ** *** ***** *** *** *
Minimu m Time Step
Average Time Step
Max imum Time Step
Percent in Steady State
Aver age Iter atio ns per Step ;
Percent No t Co nverging
* ******** **** ***** **** ****
Subcatchment Runoff Summary
** ******* ***** ***** **** ****

69.00 sec

60.00 sec

0.00 1.80

0.00 Subcatchment
Total Total Total Total Imper y Pery Total Total Peak Runoff Precip Runon Evap Infil Runo ff Runoff Runoff Runoff Runoff Coeff in in in in in in in 10^6 gal CFS
POST_DMA-5
IMP -4
PO ST_DM A-8
POST_DMA- 6
POST_DMA-7
IMP -S
IMP -6
674. 85
674. 85
674. 85
674. 85
674. 85
674. 85
674.85

0. 00
18811.04

0. 00

0.00 0. 00
16825.63
11135. 27

89.12 1180.29

0.57 50.53

78.94 1114.85
960.87

63.21 0. 00
663. 95
299.34
125.90

0.00 0.00
507. 36

0.00 8. 00
213.74
428. 66

0.00 0.00

26.98 0.00

11. 97
120.07

52.36 0.00

0.00 534.35
18304.21

11.97 333. 82
481.02
16384.41
10848.35

3.73 3 .63

0.01 1.47

9.72 1.43

9.47 0.31
0 .32

0.03 0.19

0.88 0 .19

0.92 0.792

0.939

0.018

0.495
0 .713

0.936

0.919
80 ***********************
LID Performance Summary
***********************
Subcatchment LID Control
Total Evap Infil Surface Drain Initial Final Continuity Inflow Loss Loss Outflow Outflow Storage Storage Error
in in in in in in in %
IMP -4
IMP -5
IMP -6
******************
Node Depth Summary
******************
IMP -4
IMP -5
IMP -6
19485.89 1180.33 8.00 5627.18 12677.72 2.40 3.53
17500.48 1114.91 0.00 4698.51 11686.72 2.45 3.14
11810.12 960.91 0.00 439.54 10409.24 2.40 3.06
Node
Average Maximum Maximum Time of Max Reported
Depth Depth HGL Occurrence Max Depth
Type Feet Feet Feet days hr:min Feet
POC-2
DIV
AQ
*******************
Node Inflow Summary
*******************
OUTFALL 0.00 0.50 0.50 141 07:06 0.50
DIVIDER 0.00 0.50 0.50 141 07:05 0.50
STORAGE 0.00 1.34 1.34 18857 11:51 0.85
Node Type
Maximum Maximum Lateral Total Flow
Lateral Total Time of Max Inflow Inflow Balance
Inflow Inflow Occurrence Volume Volume Error
CFS CFS days hr:min 10'6 gal 10^6 gal Percent
POC-2
DIV
AQ
*********************
Node Flooding Summary
*********************
OUTFALL 0.58 1.43 18857 11:52 14.2 14.4 0.000
DIVIDER 0.88 0.88 18857 12:01 0.384 0.384 0.000
STORAGE 8.00 0.69 18857 12:01 0 0.107 1.448
Flooding refers to all water that overflows a node, whether it ponds or not.

Node
Total Maximum
Maximum Time of Max Flood Ponded
Hours Rate Occurrence Volume Volume
Flooded CFS days hr:min 10^6 gal 1000 ft3
DIV

68.32 0.14 5200 16:59

0.150 0.000
81 - 0.00
- 8.00
- 0.00
08/11/2026
PH2 682 of 876

**********************
Storage Volume Summary
**********************
Storage Unit
Average Avg Evap Exfil Maximum Max Time of Max Maximum
Volume Pcnt Pcnt Pcnt Volume Pcnt Occurrence Outflow
1000 ft3 Fu11 Loss Loss 1000 ft3 Fu11 days hr:min CFS
AQ
***********************
Outfall Loading Summary
***********************

0.000 0 0 8 8.007 27 18857 11:51 8.88
Outfall Node
Flow Avg Max Total
Freq Flow Flow Volume
Pcnt CFS CFS 10^6 gal
POC-2

7.42 0.01

1.43 14.384
System
********************
Link Flow Summary
********************

7.42 0.01

1.43 14.384
Maximum Time of Max Maximum Max/ Max/
'Flow' Occurrence jVelocl Fu11 Fu11
Link Type CFS days hr:min ft/sec Flow Depth
Bypass
Underdrain
Outlet
DUMMY 0.69 18857 12:01
CONDUIT 0.06 14430 05:29 0.71 1.07 1.08
DUMMY 0.80 18857 11:52
*************************
Conduit Surcharge Summary
*************************
Conduit
Hours Hours
Hours Fu11 Above Fu11 Capacity
Both Ends Upstream Dnstream Normal Flow Limited
Underdrain 67.52 67.52 67.52 67.90 67.52
Analysis begun on: Tue Mar 4 14:41:49 2025
Analysis ended on: Tue Mar 4 14:42:11 2025
Total elapsed time: 08:00:22
82 08/11/2026
PH2 683 of 876

ATTACHMENT 3 - BMP MAINTENANCE INFORMATION
Each of the attachments indicated below should be considered for inclusion with the SWQMP. Use this checklist to indicate which attachments are included behind this coversheet.

Attachment
Sequence
Contents
Checklist
Attachment 3A
Structural BMP Operations
and Maintenance Plan
© Included
See Structural BMP Maintenance Information
Checklist on the back of this Attachment cover sheet.

Page 35 of 38 ends

08/11/2026
PH2 684 of 876

ATTACHMENT 3A - MAINTENANCE PLAN REQUIREMENTS
For Attachment 3A, provide a BMP operation and maintenance plan (O&M Plan). The checklist below identifies minimum elements to be included with the O&M Plan. An O&M Plan template is available at:
http://www.cityofvista.com/services/city-departments/community-development/building-planning- permits-applications/land-development-autocad-templates/storm-water-forms 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)
U Use of O&M Plan template, or plan of equivalent content 08/11/2026

Page 36 of 38 ends

PH2
685 of 876

BF -1
Biofiltration

BMP MAINTENANCE FACT SHEET
FOR
STRUCTURAL BMP BF -1 BIOFILTRATION
Biofiltration facilities are vegetated surface water systems that filter water through vegetation, and soil or engineered media prior to discharge via underdrain or overflow to the downstream conveyance system.

Biofiltration facilities have limited or no infiltration. They are typically designed to provide enough hydraulic head to move flows through the underdrain connection to the storm drain system. Typical biofiltration components include:
• Inflow distribution mechanisms (e.g., perimeter flow spreader or filter strips) • Energy dissipation mechanism for concentrated inflows (e.g., splash blocks or riprap) • Shallow surface ponding for captured flows
• Side slope and basin bottom vegetation selected based on climate and ponding depth • Non -floating mulch layer
• Media layer (planting mix or engineered media) capable of supporting vegetation growth • Filter course layer consisting of aggregate to prevent the migration of fines into uncompacted native soils or the aggregate storage layer
• Aggregate storage layer with underdrain(s)
• Impermeable liner or uncompacted native soils at the bottom of the facility • Overflow structure
Normal Expected Maintenance
Biofiltration requires routine maintenance to: remove accumulated materials such as sediment, trash or debris; maintain vegetation health; maintain infiltration capacity of the media layer; replenish mulch; and maintain integrity of side slopes, inlets, energy dissipators, and outlets. A summary table of standard inspection and maintenance indicators is provided within this Fact Sheet.

Non -Standard Maintenance or BMP Failure
If any of the following scenarios are observed, the BMP is not performing as intended to protect downstream waterways from pollution and/or erosion. Corrective maintenance, increased inspection and maintenance, BMP replacement, or a different BMP type will be required.
• The BMP is not drained between storm events. Surface ponding longer than approximately 24 hours following a storm event may be detrimental to vegetation health, and surface ponding longer than approximately 96 hours following a storm event poses a risk of vector (mosquito) breeding. Poor drainage can result from clogging of the media layer, filter course, aggregate storage layer, underdrain, or outlet structure. The specific cause of the drainage issue must be determined and corrected. • Sediment, trash, or debris accumulation greater than 25% of the surface ponding volume within one month. This means the load from the tributary drainage area is too high, reducing BMP function or clogging the BMP. This would require pretreatment measures within the tributary area draining to the BMP to intercept the materials. Pretreatment components, especially for sediment, will extend the life of components that are more expensive to replace such as media, filter course, and aggregate layers. • Erosion due to concentrated storm water runoff flow that is not readily corrected by adding erosion control blankets, adding stone at flow entry points, or minor re -grading to restore proper drainage according to the original plan. If the issue is not corrected by restoring the BMP to the original plan and grade, the [City Engineer] shall be contacted prior to any additional repairs or reconstruction.

BF -1 Page 1 of 11
January 12, 2017
08/11/2026
PH2 686 of 876

BF -1
Biofiltration
Other Special Considerations
Biofiltration is a vegetated structural BMP. Vegetated structural BMPs that are constructed in the vicinity of, or connected to, an existing jurisdictional water or wetland could inadvertently result in creation of expanded waters or wetlands. As such, vegetated structural BMPs have the potential to come under the jurisdiction of the United States Army Corps of Engineers, SDRWQCB, California Department of Fish and Wildlife, or the United States Fish and Wildlife Service. This could result in the need for specific resource agency permits and costly mitigation to perform maintenance of the structural BMP. Along with proper placement of a structural BMP, routine maintenance is key to preventing this scenario.
08/11/2026
BF -1 Page 2 of 11
January 12, 2017
PH2
687 of 876

9Z0Z/ L- L-/80
CA
CO
CO
O
CO
CA
BF -1
Biofiltration
SUMMARY OF STANDARD INSPECTION AND MAINTENANCE FOR BF -1 BIOFILTRATION The property owner is responsible to ensure inspection, operati on and maintenance of permanent BMPs on their property unless responsibility has been formally transferred to an age ncy, community facilities district, homeowners ass ociation, property owners associati on, or other special district.

Maintenance frequencies listed in this table are average/typical frequencies. Actual maintenance needs are site -specific, and maintenance may be required more frequently .

Maintenance must be performed whenever needed, based on maintenance indicators presented in this table. The BMP owner is responsible for conducting regular inspections to see when maintenance is needed based on the maintenance indicators. During the first year of operation of a structural BMP, inspection is recommended at least once prior to August 31 and then monthly from September through May . Inspecti on during a storm event is also rec ommended. After the initial period of frequent inspecti ons, the minimum inspection and maintenance frequency can be determined based on the results of the first year inspections .

Threshold/Indicato r
Maintenance Action
Typical Maintenance Frequency
Accumulation of sediment, litter, or debris
Remove and properly dispose of accumulated materials,
without damage to the vegetation or compaction of the
media layer.
• Inspect monthly . If the BMP is 25 % full* or more in one month, increase inspection frequency to monthly
plus after every 0 .1 -inch or larger storm event.
• Remove any accumulated materials found at each
inspection.

Obstructed inlet or outlet structure
Clear blockage.
• Inspect monthly and after every 0 .5 -inch or larger
storm event.
• Remove any accumulated materials found at each
inspection.

Damage to structural components such as weirs, inlet or outlet structures
Repair or replace as applicable
• Inspect annually .
• Maintenance when needed .

Poor vegetation establishment
Re -seed, re -plant, or re-establish vegetation per original plans.
• Inspect monthly.
• Maintenance when needed .

Dead or diseased vegetation
Remove dead or diseased vegetation, re -seed, re -plant, or re-establish vegetation per original plans .
• Inspect monthly.
• Maintenance when needed.

Overgrown vegetation
Mow or trim as appropriate.
• Inspect monthly.
• Maintenance when needed .
2/3 of mulch has decomposed, or mulch has been
removed
Remove decomposed fraction and top off with fresh
mulch to a total depth of 3 inches.
• Inspect monthly.
• Replenish mulch annually, or more frequently when
needed based on inspection.
*"25% full" is defined as 1/4 of the depth from the design bottom elevation to the crest of the outflow structure (e.g., if the height to the outflow opening is 12 inches from the bottom elevation, then the materials must be removed when there is 3 inches of accumulation — this sho uld be marked on the outflow structure).

BF -1 Page 3 of 11
January 12, 2017

9Z0Z/ L- L-/80
C)
CO
O
CO
CA
BF -1
Biofiltration
SUMMARY OF STANDARD INSPECTION AND MAINTENANCE FOR BF -1 BIOFILTRATION (C ontinued from previ ous page) Threshold/Indicator
Maintenance Action
Typical Maintenance Frequency
Erosion due to concentrated irrigation fl ow
Repair/re-seed/re-plant eroded areas and adjust the
irrigation system .
• Inspect monthly.
• Maintenance when needed.

Erosion due to concentrated storm water runoff flow
Repair/re-seed/re-plant eroded areas, and make
appropriate corrective measures such as adding erosion
control blankets, adding stone at flow entry points, or min or re -grading to restore proper drainage according to the original plan . If the issue is not corrected by restoring the BMP to the original plan and grade, the
[City Engineer] shall be contacted prior to any additional repairs or reconstruction.
• Inspect after every 0.5 -inch or larger storm event . If erosion due to storm water fl ow has been observed,
increase inspection frequency to after every 0 .1 -inch or larger storm event .
• Maintenance when ne eded . If the issue is not
corrected by restoring the BMP to the original plan
and grade, the [City Engineer] shall be contacted prior to any additional repairs or reconstruction.

Standing water in BM P for longer than 24 hours
following a storm event
Surface ponding longer than approximately 24 hours
following a storm event may be detrimental to
ve getation health
Make appropriate corrective measures such as adjusting
irrigation system, removing obstructions of debris or
invasive vegetation, clearing underdrains, or
repairing/r eplacing clogged or c ompacted soils.
• Inspect monthly and after every 0.5 -inch or larger
storm event. If standing water is observed, increase
inspection frequency to after every 0.1 -inch or larger storm event.
. Maintenance when needed.

Presence of mosquitos/larvae
For images of egg rafts, larva, pupa, and adult
mosquitos, see
http://www.mosquito.org/biology
If mosquitos/larvae are observed: first, immediately
remove any standing water by dispersing to nearby
landscaping; second, make c orrective measures as
applicable to restore BMP drainage to prevent standing
water.

If mosquitos persist following corrective measures to
remove standing water, or if the BMP design does not
meet the 96 -hour drawdown criteria due to release
rates controlled by an orifice installed on the
underdrain, the [City Engineer] shall be contacted to
determine a solutio n. A different BMP type, or a Vect or Management Plan prepared with concurrence from the
County of San Diego Department of Environmental
Health, may be required.
• Inspect monthly and after every 0 .5 -inch or larger
storm event. If mosquitos are observed, increase
inspection frequency to after every 0.1 -inch or larger storm event.
• Maintenance when needed .

Underdrain clogged
Clear blockage.
• Inspect if standing water is observed for longer than 24-96 hours following a storm event.
• Maintenance when needed.

BF -1 Page 4 of 11
January 12, 2017

9Z0Z/ L- L-/80
References
American Mosquito Control Association.
http://www.mosquito.org/
California Storm Water Quality Association (CASQA). 2003 . Municipal BMP Handbook. https://www.casga.org/resources/bmp-handbooks/municipal-bmp-handbook County of San Diego. 2014 . Low Impact Development Handbook . http://www.sandiegocounty.gov/content/sdc/dpw/watersheds/susmp/lid.html San Diego County Copermittees. 2016. Model BMP Design Manual, Appendix E, Fact Sheet BF -1. http://www.projectcleanwater.org/index.php?option=com content&view=article&id=250&Itemid=220 BF -1 Page 5 of 11
January 12, 2017
BF -1
Biofiltration

9Z0Z/ L- L-/80
I
N
O)
CD
O
CO
O)
Page Intentionally Blank for Double -Sided Printing
BF -1 Page 6 of 11
January 12, 2017
BF -1
Biofiltration

9Z0Z/ L- L-/80
BF -1
Biofiltration
Date:

Inspector: BMP ID No.:

Permit No.:

APN(s):

Property / Development Name:

Responsible Party Name and Phone Number:

Property Address of BMP:

Responsible Party Address:

INSPECTION AND MAINTENANCE CHECKLIST FOR BF -1 BIOFILTRATION PAGE 1 of 5 Threshold/Indicato r
Maintenance R ecomm endation
Date
Description of Maintenance Conducted
Accumulation of sediment, litter, or debris
Maintenance Needed?
❑ YES
❑ NO
❑ N/A
❑ Remove and properly dispose of
accumulated materials, without damage
to the vegetation
❑ If sediment, litter, or debris accumulation
exceeds 25 % of the surface ponding
volume within one month (25% full *),
add a forebay or other pre-treatment
measures within the tributary area
draining to the BMP to intercept the
materials.
❑ Other / Comments:

Poor vegetation establishment
Maintenance Needed?
❑ YES
❑ NO
❑ N/A
❑ Re -seed, re -plant, or re-establish
vegetation per original plans
❑ Other / Comments:
* "25% full" is defined as1/4 of the depth from the design bottom elevation to the crest of the outflow structure (e. g. , if the height to the outflow opening is 12 inches from the bottom elevation, then the materials must be removed when there is 3 inches of accumulation — this should be marked on the outflow structure) .

BF -1 Page 7 of 11
January 12, 2017

9Z0Z/ L- L-/80
BF -1
Biofiltration
Date:

Inspector:

BMP ID No.:

Permit No.:

APN(s):

INSPECTION AND MAINTENANCE CHECKLIST FOR BF -1 BIOFILTRATI ON PAGE 2 of 5 Threshold/Indicator
Maintenance Recommendation
Date
Description of Maintenance Conducted
Dead or diseased vegetation
Maintenance Needed?
❑ YES
❑ NO
❑ N/A
❑ Remov e dead or diseased vegetation, re -
seed, re -plant, or re-establish vegetation
per original plans
❑ Other/ Comments:

Overgrown vegetatio n
Maintenance Needed?
❑ YES
❑ NO
❑ N/A
❑ Mow or trim as appropriate
❑ Other / Comments:
2/3 of mulch has decomposed, or mulch has
been remo ved
Maintenance Needed?
❑ YES
❑ NO
❑ N/A
❑ Remove decomposed fraction and top off
with fresh mulch to a to tal depth of 3
inches
❑ Other / Comments:

BF -1 Page 8 of 11
January 12, 2017

9Z0Z/ L- L-/80
BF -1
Biofiltration
Date:

Inspector:

BMP ID No.:

Permit No.:

APN(s):

INSPECTION AND MAINTENANCE CHECKLIST FOR BF -1 BIOFILTRATI ON PAGE 3 of 5 Threshold/Indicator
Maintenance Recommendation
Date
Description of Maintenance Conducted
Erosion due to concentrated irrigation flow
Maintenance Needed?
❑ YES
❑ NO
❑ N/A
❑ Repair/re-seed/re-plant eroded areas and
adjust the irrigation system
❑ Other / Comments:

Erosion due to concentrated storm water runoff
flow
Maintenance Needed?
❑ YES
❑ NO
E N/A
❑ Repair/re-seed/re-plant eroded areas,
and make appropriate corrective
measures such as adding erosion
control blankets, adding stone at flow
entry points, or minor re -grading to
restore proper drainage according to
the original plan
❑ If the issue is not corrected by restoring
the BMP to the original plan and grade,
the [City Engineer] shall be contacted
prior to any additional repairs or
reconstruction
❑ Other / Comments:

BF -1 Page 9 of 11
January 12, 2017

9Z0Z/ L- L-/80
BF -1
Biofiltration
Date:

Inspector:

BMP ID No.:

Permit No.:

APN(s):

INSPECTION AND MAINTENANCE CHECKLIST FOR BF -1 BIOFILTRATI ON PAGE 4 of 5 Threshold/Indicator
Maintenance Recommendation
Date
Description of Maintenance Conducted
Obstructed inlet or outlet structure
Maintenance Needed?
❑ YES
❑ NO
❑ N/A
❑ Clear blockage
❑ Other / Comments:

Underdrain clogged (inspect underdrain if
standing water is observed for longer than 24-96
hours following a storm event)
Maintenance Needed?
❑ YES
❑ NO
❑ N/A
❑ Clear blockage
El Other / Comments:

Damage to structural components such as weirs,
inlet or outlet structures
Maintenance Needed?
❑ YES
❑ NO
❑ N/A
❑ Repair or replace as applicable
❑ Other / Comments:

BF -1 Page 10 of 11
January 12, 2017

9Z0Z/ L- L-/80
BF -1
Biofiltration
Date:

Inspector:

BMP ID No.:

Permit No.:

APN(s):

INSPECTION AND MAINTENANCE CHECKLIST FOR BF -1 BIOFILTRATI ON PAGE 5 of 5 Threshold/Indicator
Maintenance Recommendation
Date
Description of Maintenance Conducted
Standing water in BMP for longer than 24-96
hours following a storm event*
Surface ponding longer than approximately 24
hours follo wing a storm event may be
detrimental to vegetation health
Maintenance Needed?
❑ YES
❑ NO
❑ N/A
❑ Make appropriate corrective measures
such as adjusting irrigation system,
removing obstructions of debris or
invasive vegetation, clearing
underdrains, or repairing/replacing
cl ogged or compacted soils
❑ Other / Comments:

Presence of mo squito s/larvae
For images of egg rafts, larva, pupa, and adult
mosquitos, see
http://www.mosquito.org/biologv
❑ Apply corrective measures to remove
standing water in BMP when standing
water occurs for longer than 24-96
ho urs following a storm event.**
E Other / Comments:

Maintenance Needed?
❑ YES
❑ NO
E N/A
* Surface ponding longer than approximately 24 hours following a storm event may be detrimental to vegetation health, and surface ponding longer than approximately 96 hours fo llowing a storm event poses a risk of vector (mosquito ) breeding. Poo r drainage can result from clogging of the media layer, filter c ourse, aggregate storage layer, underdrain, or o utlet structure. The specific cause of the drainage issue must be determined and corrected. **If mo squito s persist following corrective measures to remove standing water, or if the BMP design do es not meet the 96 -hour drawdown criteria due to release rates controlled by an orifice installed on the underdrain, the [City Engineer] shall be contacted to determine a solution. A different BMP type, or a Vector Management Plan prepared with concurrence from the County of San Diego Department of Environmental Health, may be required.

BF -1 Page 11 of 11
January 12, 2017

SD -1
Tree Wells

BMP MAINTENANCE FACT SHEET
FOR
SITE DESIGN BMP SD -1 TREE WELLS
Tree wells as site design BMPs are trees planted in configurations that allow storm water runoff to be directed into the soil immediately surrounding the tree. The tree may be contained within a planter box or structural cells. The surrounding area will be graded to direct runoff to the tree well. There may be features such as tree grates, suspended pavement design, or shallow surface depressions designed to allow runoff into the tree well. Typical tree well components include:
• Trees of the appropriate species for site conditions and constraints • Available growing space based on tree species, soil type, water availability, surrounding land uses, and project goals
• Entrance/opening that allows storm water runoff to flow into the tree well (e.g., a curb opening, tree grate, or surface depression)
• Optional suspended pavement design to provide structural support for adjacent pavement without requiring compaction of underlying layers
• Optional root barrier devices as needed; a root barrier is a device installed in the ground, between a tree and the sidewalk, intended to guide roots down and away from the sidewalk in order to prevent sidewalk lifting from tree roots
• Optional tree grates; to be considered to maximize available space for pedestrian circulation and to protect tree roots from compaction related to pedestrian circulation; tree grates are typically made up of porous material that will allow the runoff to soak through • Optional shallow surface depression for ponding of excess runoff • Optional planter box drain
Normal Expected Maintenance
Tree health shall be maintained as part of normal landscape maintenance. Additionally, ensure that storm water runoff can be conveyed into the tree well as designed. That is, the opening that allows storm water runoff to flow into the tree well (e.g., a curb opening, tree grate, or surface depression) shall not be blocked, filled, re -graded, or otherwise changed in a manner that prevents storm water from draining into the tree well. A summary table of standard inspection and maintenance indicators is provided within this Fact Sheet.

Non -Standard Maintenance or BMP Failure
Tree wells are site design BMPs that normally do not require maintenance actions beyond routine landscape maintenance. The normal expected maintenance described above ensures the BMP functionality. If changes have been made to the tree well entrance / opening such that runoff is prevented from draining into the tree well (e.g., a curb inlet opening is blocked by debris or a grate is clogged causing runoff to flow around instead of into the tree well, or a surface depression has been filled so runoff flows away from the tree well), the BMP is not performing as intended to protect downstream waterways from pollution and/or erosion. Corrective maintenance will be required to restore drainage into the tree well as designed.

Surface ponding of runoff directed into tree wells is expected to infiltrate/evapotranspirate within 24-96 hours following a storm event. Surface ponding longer than approximately 24 hours following a storm event may be detrimental to vegetation health, and surface ponding longer than approximately 96 hours following a storm event poses a risk of vector (mosquito) breeding. Poor drainage can result from clogging or compaction of the soils surrounding the tree. Loosen or replace the soils to restore drainage.

SD -1 Page 1 of 6
January 12, 2017
08/11/2026
PH2 697 of 876

SD -1
Tree Wells
Other Special Considerations
Site design BMPs, such as tree wells, installed within a new development or redevelopment project are components of an overall storm water management strategy for the project. The presence of site design BMPs within a project is usually a factor in the determination of the amount of runoff to be managed with structural BMPs (i.e., the amount of runoff expected to reach downstream retention or biofiltration basins that process storm water runoff from the project as a whole). When site design BMPs are not maintained or are removed, this can lead to clogging or failure of downstream structural BMPs due to greater delivery of runoff and pollutants than intended for the structural BMP. Therefore, the [City Engineer] may require confirmation of maintenance of site design BMPs as part of their structural BMP maintenance documentation requirements. Site design BMPs that have been installed as part of the project should not be removed, nor should they be bypassed by re-routing roof drains or re -grading surfaces within the project. If changes are necessary, consult the [City Engineer] to determine requirements.
08/11/2026
SD -1 Page 2 of 6
January 12, 2017
PH2
698 of 876

9Z0Z/ L- L-/80
SD -1
Tree Wells
SUMMARY OF STANDARD INSPECTI ON AND MAINTENANCE FOR SD -1 TREE WELLS The property owner is responsible to ensure inspection, operation and maintenance of permanent BMPs on their property unless responsibility has been formally transferred to an agency, community facilities district, homeowners association, property owners ass ociation, or other special district.

Maintenance frequencies listed in this table are average/typical frequencies . Actual maintenance needs are site -specific, and maintenance may be required more frequently .

Maintenance must be performed whenever needed, based on maintenance indicators presented in this table . The BMP owner is responsible for conducting regular inspections to see when maintenance is needed based on the maintenance indicators. During the first year of operation of a structural BMP, inspection is recommended at least once prior to August 31 and then monthly from September through May. Inspection during a storm event is also recommended . After the initial period of frequent inspections, the minimum inspection and maintenance frequency can be determined based on the results of the first year inspecti ons.

Threshold/Indicator
Maintenance Action
Typical Maintenance Frequency
Tree health
R outine actions as necessary to maintain tree health . • Inspect monthly .
• Maintenance when needed.

Dead or diseased tree
Remove dead or diseased tree . Replace per original
plans.
• Inspect monthly.
• Maintenance when needed.

Standing water in tree well for longer than 24 hours
following a storm event
Surface ponding longer than approximately 24 hours
fo llowing a storm eve nt may be detrimental to tree
health
Loosen or replace soils surrounding the tree to restore drainage .
• Inspect monthly and after every 0 .5 -inch or larger
storm event. If standing water is observed, increase
inspection frequency to after every 0.1 inch or larger
storm event.
• Maintenance when needed .

Presence of mosquitos/larvae
Fo r images of egg rafts, larva, pupa, and adult
mosquitos, see
http://www.mosquito.org/biology
Disperse any standing water from the tree well to
nearby landscaping. Loosen or replace soils surrounding the tree to restore drainage (and prevent standing
water).
• Inspect monthly and after every 0.5 -inch or larger
storm event. If m osquit os are observed, increase
inspection frequency to after every 0.1 -inch or larger storm event.
• Maintenance when needed
Entrance / o pening to the tree well is blo cked such that sto rm water will not drain into the tree well (e.g., a curb inlet opening is blocked by debris or a grate is clogged causing runoff to flow around instead of into the tree
well; or a surface depression is filled such that runoff drains away from the tree well)
Make repairs as appropriate to rest ore drainage into the tree well.
• Inspect monthly .
• Maintenance when needed.

SD -1 Page 3 of 6
January 12, 2017

9Z0Z/ L- L-/80
References
American Mosquito Control Association.
http://www .mosquito .org/
County of San Diego. 2014 . Low Impact Development Handbook . http://www.sandiegocounty.gov/content/sdc/dpw/watersheds/susmp/lid.html San Diego County Copermittees. 2016. Model BMP Design Manual, Appendix E, Fact Sheet SD -1. http://www.proiectcleanwater.org/index.ph D?option=com content&view=article&id=250&Itemid=220 SD -1 Page 4 of 6
January 12, 2017
SD -1
Tree Wells

9Z0Z/ L- L-/80
SD -1
Tree Wells
Date:

Inspector: BMP ID No.:

Permit No.:

APN(s):

Property / Development Name:

Responsible Party Name and Phone Number:

Property Address of BMP:

Responsible Party Address:

INSPECTION AND MAINTENANCE CHECKLIST FOR SD -1 TREE WELLS PAGE 1 of 2 Threshold/Indicato r
Maintenance R ecomm endation
Date
Description of Maintenance Conducted
Dead or diseased tree
Maintenance Needed?
❑ YES
❑ NO
❑ N/A
❑ Remove dead or diseased tree
❑ Replace per original plans
❑ Other / Comments:

SD -1 Page 5 of 6
January 12, 2017

9Z0Z/ L- L-/80
SD -1
Tree Wells
Date:

Inspector:

APN(s):

BMP ID No.:

Permit No.:

INSPECTION AND MAINTENANCE CHECKLIST FOR SD -1 TREE WELLS PAGE 2 of 2 Threshold/Indicator
Maintenance R ecomme ndation
Date
Description of Maintenance Conducted
Presence of mosquitos/larvae
Fo r images of egg rafts, larva, pupa, and
mosquitos, see
http://www.moscuito.org//biology
Maintenance Needed?
❑ YES
❑ NO
❑ N/A
adult
❑ Disperse any standing water from the tree
well to nearby landscaping
❑ Loosen or replace soils surrounding the
tr ee to r estore drainag e (and prevent
standing water)
❑ Other / Comments:

Entrance / opening to the tree well is blocked
such that storm water will not drain into the
tree well (e.g., a curb inlet opening is blocked by
debris or a grate is clogged causing runoff to
flow around instead of into the tree well; or a
surface depression is filled such that runoff
drains away from the tree well)
Maintenance Needed?
❑ YES
❑ NO
❑ N/A
❑ Make repairs as appropriate to restore
drainage into the tree well
❑ Other / Comments:

SD -1 Page 6 of 6
January 12, 2017

`�`GSAowMWAT[_R Sy TF17
s
AQuaSavc
TANKS

AQUASAVE OPERATION & MAINTENANCE MANUAL
Operation
Your AquaSave System has been designed to function in conjunction with the engineered drainage system on your site, the existing municipal infrastructure, and/or the existing soils and geography of the receiving watershed. Unless your site included certain unique and rare features, the operation of your AquaSave System will be driven by naturally occurring systems and will function autonomously. However, upholding a proper schedule of Inspection & Maintenance is critical to ensuring continued functionality and optimum performance of the system.

Inspection
Both the AquaSave system and all stormwater pre-treatment features incorporated into your site must be inspected regularly. Inspection frequency for your system must be determined based on the contributing drainage area, butshould never exceed one year between inspections (six months during the first year of operation).

Inspections may be required more frequently for pre-treatment systems. You should refer to the manufacturer requirements for the proper inspection schedule.

With the right equipment your inspection and measurements can be accomplished from the surface without physically entering any confined spaces. If your inspection does require confined space entry, you MUST follow all local/regional requirements as well as OSHAstandards.

AquaSave Systems may incorporate Inspection Ports, Maintenance Ports, and/or adjoining manholes. Each of these features are easily accessed by removing the lid at the surface. With the cover removed, a visual inspection can be performed to identify sediment deposits within the structure. Using a flashlight, ALL access points should be examined to complete a thorough inspection.

Inspection Ports
Usually located centrally in the System, these perforated columns are designed to give the user a base -line sediment depth across the system floor.

Maintenance Ports
Usually located near the inlet and outlet connections, you'll likely find deeper deposits of heavier sediments when compared to the Inspection Ports.

Manholes
Mostsystems will include at leasttwo manholes- one atthe inlet and anotheratthe outlet. There may be more than one location where stormwater enters the system, which would result in additional manholes to inspect.

Bear in mind that these manholes often include a sump below the invert of the pipe connecting to the system.

These sumps are designed to capture sediment before it reaches the system, and they should be kept clean to ensure they function properly. However, existence of sediment in the sump does NOT necessarily mean sediment has accumulated in the system.

After inspecting the bottom of the structure, use a mirror on a pole (or some other device) to check for sediment or debris in the pipe connecting to the system.
08/11/2026
PH2 703 of 876

If sediment or debris is observed in any of these structures, you should determine the depth of the material. This is typically accomplished with a stadia rod, but you should determine the best way to obtain the measurement.

All observations and measurements should be recorded on an Inspection Log kept on file. We've included a form you can use at the end of this guideline.

Maintenance
The AQUASAVE System should be back -flushed once sediment accumulation has reached 6" or 15% of the total system height.

Before any maintenance is performed on your system, be sure to plug the outlet pipe to prevent contamination of the adjacent systems.

To back -flush the system, water is pumped into the system through the Maintenance Ports as rapidly as possible. Water should be pumped into ALL Maintenance Ports. The turbulent action of the water moving through the system will suspend sediments which may then be pumped out.

If your system includes an Outlet Structure, this will be the ideal location to pump contaminated water out of the system. However, removal of back -flush water may be accomplished through the Maintenance Ports, as well.

For systems with large footprints that would require extensive volumes of water to properly flush the system, you should consider performing your maintenance within 24 hours of a rain event.

Stormwater entering the system will aid in the suspension of sediments and reduce the volume of water required to properly flush the system.

Once removed, sediment -laden water may be captured for disposal or pumped through a DirtbagTM (if permitted by the locality).
08/11/2026
PH2 704 of 876

Step -By -Step Inspection & Maintenance Routine
1) Inspection
a. Inspection Port
i. Remove Cap
ii. Use flashlight to detect sediment deposits
iii. If present, measure sediment depth with stadia rod iv. Record results on Maintenance Log
v. Replace Cap
b. Maintenance Port/s
i. Remove Cap
ii. Use flashlight to detect sediment deposits
iii. If present, measure sediment depth with stadia rod iv. Record results on Maintenance Log
v. Replace Cap
vi. Repeat for ALL Maintenance Ports
c. Adjacent Manholes
i. Remove Cover
ii. Use flashlight to detect sediment deposits
iii. If present, measure sediment depth with stadia rod, accounting for depth of sump (if present)
iv. Inspect pipes connecting to system
v. Record results on Maintenance Log
vi. Replace Cover
vii. Repeat for ALL Manholes that connect to the system 2) Maintenance
a. Plug system outlet to prevent discharge of back -flush water b. Determine best location to pump out back -flush water c. Remove Cap from Maintenance Port
d. Pump water as rapidly as possible (without over -topping port) into system until at least 1"
of water covers system bottom
e. Replace Cap
f. Repeat at ALL Maintenance Ports
g. Pump out back -flush water to complete back -flushing h. Vacuum all adjacent structures and any other structures or stormwater pre-treatment systems that require attention
i. Sediment -laden water may be captured for disposal or pumped through a DirtbagTM. j. Replace any remaining Caps orCovers
k. Record the back -flushing event in your Maintenance Log with any relevant specifics 08/11/2026
PH2 705 of 876

Maintenance Log
0 °Site Name:

R3Lo catio n:
0 N
0)System Owner:

I
N)
9L8 40 90L
C ompany Resp onsible
f or Maintenance:

C ontact:

Phone Numer:

For more info rmation about our pro duc ts, co ntac t Inside Sale s at 800.448.3636 or e mail at info@ ac fenv.com

ATTACHMENT 3B - MAINTENANCE AGREEMENT
All projects are required to maintain designed functionality of structural BMPs in perpetuity. Privately - owned projects must record a Storm Drain Maintenance Agreement with the County of San Diego Assessor's Office. A template Storm Drain Maintenance Agreement is available at:
http://www.cityofvista.com/services/city-departments/community-development/buildin7,-planning- permits-applications/land-development-autocad-templates/storm-water-forms 08/11/2026

Page 37 of 38 ends

Vista City CouncilAugust 11, 2026

Vista City Council
August 11, 2026