Job No. 20109009
200 Fourth Street, Suite 300, Santa Rosa, CA 95401 | 707.583.8500
FINAL
STORMWATER LID SUBMITTAL
FOR
ELEM TREE STATION
874 NORTH WRIGHT ROAD
SANTA ROSA, CA
APN (035-063-001)
DECEMBER 2018
Developer/Owner:
MD Wine and Liquor
2743 Yulupa Avenue
Santa Rosa, CA 95404
(775) 546-7500
Attachment 20
109009_SWLID.docx | P a g e 3
TABLE OF CONTENTS
SECTION PAGE
GENERAL INFORMATION REGARDING THE PURPOSE OF STORM WATER BMPS ........................... 4 STORM WATER BMPS SELECTED FOR THIS SITE ............................................................................. 5 MAINTENANCE OF THE SELECTED PERMANENT STORM WATER BMPS ........................................ 7
APPENDIX PAGE
POST DEVELOPMENT EXHIBIT ......................................................................................................... 8 VOLUME CAPTURE CALCULATIONS ................................................................................................ 9 BIOSWALE MEDIA MIX MATERIAL DATA SHEET ............................................................................. 9 DETERMINATION WORKSHEET ..................................................................................................... 10 SUSMP SUBMITTAL GUIDE CHECKLIST ......................................................................................... 10 BMP SELECTION TABLES ............................................................................................................... 10 BIORETENTION AREA FACT SHEET ................................................................................................ 11 VEGETATED SWALE FACT SHEET ................................................................................................... 11 SAMPLE OPERATION AND MAINTENANCE INSPECTION CHECKLISTS .......................................... 12 DRAFT MAINTENANCE DECLARATION .......................................................................................... 13 109009_SWLID.docx | P a g e 4
GENERAL INFORMATION REGARDING THE PURPOSE OF STORM WATER BMPS
Storm water runoff Best Management Practices (BMPs) are programs, processes or engineered systems designed to reduce pollutants in storm water. Temporary Best Management Practices such as straw wattle and silt fence are used to reduce pollutants in storm water during construction while permanent storm water Best Management Practices are intended to reduce pollutants in storm water for the life of the development following construction.
Studies suggest that approximately 85% of our annual rainfall volume is produced from the predominant population of smaller storms. Therefore, in an effort to treat storm water in a cost effective manner, storm water quality management is typically designed to target these smaller events.
The Low Impact Development Technical Design Manual
The manual requires that a “Determination Worksheet” be prepared by the Applicant to evaluate whether or not stormwater BMPs are required with each development. Developments which require permanent stormwater BMPs also require a mainten ance agreement between the municipality and the legally responsible entity which assigns the responsibility for maintaining BMPs. The agreement is recorded as a covenant, runs with the land and passes with Title. A copy of the maintenance agreement that has been provided to the City is included in the appendix of this report.
Permanent stormwater Best Management Practices are categorized in the LID Technical Design Manual as being Pollution Prevention Measures, Volume Control Measures or Treatment Control Measures, which are described in the following sections of this document.
Permanent storm water Best Management Practices are categorized in the LID Technical Design Manual as being Pollution Prevention Measures, Volume Control Measures or Treatme nt Control Measures which are described in the following sections of this document.
Storm Water Pollution Prevention Measures
Pollution Prevention Measures, sometimes referred to as Source Control Measures, are practices such as street sweeping which help keep pollutants from coming into contact with storm water rather than attempting to remove pollutants after they have interacted with storm water. Educational outreach programs and stenciling storm water inlets with graphics which inform people that the storm water drains to the creek are effective Pollution Prevention Measures. Trees are another effective Pollution Prevention Measure and provide several storm water management benefits. They hold water on leaves / branches and allow water to evaporate, retaining flow and dissipating the energy of runoff. Trees also reduce the amount of water coming into contact with other impervious surfaces such as parking lots, which minimizes pollution in downstream water bodies
Our local municipalities recognize the environmental benefit to incorporating Pollution Prevention Measures into designs and allow area offset credits with the implementation of trees which intercept falling precipitation, pervious pavements which encourag e infiltration and storm water discharge through landscape areas as a pre -treatment measure. The pollution prevention credits reduce the size of required Volume and Treatment Control Measures.
Storm Water Volume Control Measures
The LID Technical Design Manual prioritizes BMPs and requires that the designer first consider measures which capture stormwater runoff from impervious surfaces and encourage infiltration. Developments in areas subject to contaminated soil or high groundwater are discouraged from integrating measures which infiltrate stormwater and are required to incorporate alternative designs which harvest stormwater and treat runoff from impervious surfaces.
Offset areas are sometimes used within a site when it is more practical to treat storm water from and existing impervious surface of similar character.
Storm Water Treatment Control Measures
109009_SWLID.docx | P a g e 5
Treatment Control BMPs are engineered systems that are designed to remove pollutants from stormwater and are often categorized as being landscape-based or mechanical.
Landscape-based treatment controls are required to make up at least 50% of a BMP. Mechanical treatment controls such as subsurface vaults that filter stormwater through sand or engineered media are generally only allowed when used in conjunction with other landscape based controls.
All treatment control BMPs for this project are categorized as Bioretention Areas.
PROJECT DESCRIPTION
The project site, APN 035 -063-001, is a currently undeveloped parcel located on the western edge of Santa Rosa along North Wright Road. Most of the approximately 1.12 acre site is proposed to be developed for construction of a retail market, gas service station, electric car recharging station and a small commercial building. Both construction and final vehicle access to the development will be provided at North Wright Road . The parcel is bordered by Blue Star Gas to the south (APN 035-063-002), undeveloped land to the east (APN 035-063-005) and the Joe Rodota Trail to the north (APN 035-051-028 and APN 035-063-061).
Permanent Storm Water Best Management Practices are required with this development because the project requires a building permit for a new structure and it proposes more than 10,000sf of new impervious surfaces. The improvement will create less than one acre of impervious area. Since this project proposes to impact an existing isolated wetlands area, a 401 clean water certification from the Regional Water Quality Control Board and 404 permit from the Army Corps of Engineers are required. Therefore, the proposed BMPs will be reviewed by these agencies simultaneously with the City of Santa Rosa Engineering Department review.
The area-wide drainage is currently overland flow with numerous depressions which catch rainw ater in pools and shallow swales. The lands to the east and south of this site generally flow in a westerly direction. The development proposes to integrate a series of Bioretention Areas which capture site runoff during light precipitation events in accordance with the priority 1 objective of the City’s LID Technical Design Manual. Storm water for larger events is anticipated to drain similar to the pre-developed condition, utilizing the existing established storm drain system.
The site has been designed to have positive gradients away from structures with overland relief.
STORM WATER BMPS SELECTED FOR THIS SITE
This project has been designed to incorporate temporary and permanent stormwater Best Management Practices to minimize the introduction of pollutants in downstream water bodies.
Pollutants of Concern
The primary pollutants of concern for this project are: liquefied hydrocarbons, sediments, trash, and debris. Spill prevention measures will be implemented as required by the Santa Rosa Fire Department, the fueling canopy will discourage rainwater from washing small amounts of fuel into the storm drain, and a diversion valve on the downstream stormdrain inlet should be install ed to divert larger spills from entering the stormdrain system.
Sediments due to exposed dirt during construction are required to be contained within the site by using temporary erosion and sediment control measures. The vegetated Bioretention Area has been designed to treat or remove the aformentioned pollutants of concern to the maximum extent practical. The surface of the Bioretention Area should be planted with a dense ground over to help capture trash.
Temporary Measures
An Erosion Control Plan is included with the construction drawings requiring the contractor to implement temporary stormwater BMPs. The contractor will be required to use fiber rolls or similar measures to collect sediment and filter water before allowing its discharge to downstream a reas. A construction entrance is shown on the drawings as having a blanket of rock to assist with removing dirt from trucks to minimize soil tracked into adjacent streets during construction.
109009_SWLID.docx | P a g e 6
Pollution Prevention Measures
As part of this project, storm water inlets will be stenciled with graphics which identify that the inlets drain to the creek. The trash enclosure will be roofed, and the surrounding pavement has been designed to prevent storm water from entering the enclosure. Irrigation systems will be designed to minimize overspray to help prevent chlorinated water from entering the storm drain.
Pollution Prevention Credits
The LID Technical Design Manual allows area offset credits with the implementation of certain Pollution Prevention Measures. New trees will be planted with this development creating an opportunity to intercept precipitation from falling on impervious surfaces beneath them. Tree reduction credit computations were performed using the municipality’s storm water calculator and may be observed in the appendix of this report.
Permanent Volume Control Measures
The Storm Water LID Technical Design Manual requires that measures be incorporated into each site which capture storm water runoff from impervious surfaces and encourage infiltration for the life of the development following construction. The low percolation rate of Sonoma County soils does make infilt ration a challenging objective. The LID manual acknowledges this, suggesting that designs incorporate engineered media and similar mechanisms which create void space to store water and allow infiltration over time.
Vegetated Swales containing porous engineered media are being incorporated into the site to capture the post development storm water runoff during light precipitation events and encourage infiltration in harmony with the Priority 1 objectives of t he LID Technical Design Manual. An exhibit has been included in the body of this report which reflects the proposed geometry and location of the Vegetated Swales.
A Landscape Architect was retained to design attractive water efficient landscaping best suited on the surface of the volume capture areas and tree species best suited to be classified as “interceptor trees” . An exhibit has been included in the body of this report which reflects the proposed location of each interceptor tree.
The Soil Conservation Service, known today as the Natural Resource Conservation Service, developed a process to estimate storm water runoff and compute storm water volumes for rese rvoirs in small watersheds. This process is based on a soil designation relating to how well the underlying soil drains and a curve number which reflects the runoff condition. The LID manual developed by the City of Santa Rosa and County of Sonoma sugges ts that this method be used when determining the volume of water which should be stored for the 85th percentile storm (defined in the Santa Rosa and Sonoma County areas as generating approximately 1-inch of precipitation) in order to emulate the predevelopment condition.
A geotechnical report for the site was prepared by Bauer Associates dated October 16, 2012. The report indicates that the site is primarily overlain by porous natural sandy clays of moderate to high expansion potential. The se surface soils would typically be classified a class D type soil having an infiltration rate of 0 to 0.05in/hr. According to the report groundwater was observed in the test borings at between 7 and 12 feet below the surface . The “State Water Resources Cont rol Board’s ” “GeoTracker” system was observed and does not report groundwater contamination within 50ft of proposed storm water treatment areas.
Given the depth to ground water and the fact that there appear s to be no reported active groundwater contamination sites in close proximity to the proposed BMPs, the integration of storm water BMPs which infiltrate water is feasible with this project ; and, it may not be necessary to integrate a subsurface liner or subdrain system for the Bioretention Areas. Therefore, BMPs are proposed which are in harmony with the priority 1 objectives in the LID Technical Design Manual.
Computations were prepared to size each Bioretention Area using the municipality’s storm water calculator to assess the post development storm water runoff volume. The civil drawings recommend that Bioswale Media Mix having a porosity of at least 60% be used throughout the private Bioretention Areas to achieve the required capture volume. 109009_SWLID.docx | P a g e 7
A material data sheet has been included with the calc ulations which suggest that this material is available having a porosity of nearly 65%. A porosity of 60% was used to conservatively assess the required capture volume and slightly increase storage to accommodate sediment accumulation. The bioretention areas east of the bike path are shown on the civil drawings as using City of Santa Rosa Structural soil having a porosity of at least 30% due to the proximity of these areas to property lines and the path which is expected to see occasional maintenance vehi cle traffic.
Computations are shown in the Appendix of this document and reflect that the void space in the proposed measures exceeds the required storm water capture volume.
MAINTENANCE OF THE SELECTED PERMANENT STORM WATER BMPs
Maintenance of permanent storm water Best Management Practices is essential to ensure that the BMPs continue to function effectively and that they do not become a nuisance. An exhibit has been included in the body of this report which identifies the locations of the permanent storm water BMPs referred to in this report which will require inspection and maintenance. It is the responsibility of the Applicant/Owner to ensure that permanent storm water BMPs are installed and maintained in accordance with municipal policy until this responsibility is legally transferred.
The Regional Water Quality Control Board requires the legally responsible party to inspect and maintain permanent storm water BMPs at least once a year. A sample inspection and reporting template has been i ncluded in the Appendix of this document for reference. Reports which document maintenance activities should be completed when maintenance is performed and kept on file for a period of at least five years. These reports shall be made available to City staff and the Regional Water Quality Control Board staff upon request.
The maintenance of permanent storm water Best Management Practices will be performed by the property owner and includes things such as pruning, weeding, mowing, trash/sediment removal, and the inspection/replacement of plants and media. The LID Technical Design Manual requires that the owner enter into a signed agreement and that this agreement be recorded as a perpetual covenant which runs with the land. The maintenance agreement has been included in the Appendix of this document for reference. Every site requires some level of maintenance such as sweeping, restriping, pavement replacement, irrigation repair and replanting. The following inspection and maintenance activities are additional measures which are necessary with this development as a result of the required permanent storm water BMPs:
Drainage inlets will be stenciled with verbiage or a graphic which suggests that the storm water system drains to a creek. Stenciling should b e refreshed every 5 years. If the BMP has been removed or has experienced significant fading, then the BMP should be replaced. The surface of volume capture areas should be inspected on a quarterly basis, and following larger storm events for signs of e rosion, damage to vegetation, foreign debris and sediment accumulation. The BMP should be repaired to maintain its character and function in substantial conformance with the original design.
Additional information has been included in the Appendix of this report which describes the function and recommended maintenance of measures proposed in this report.
Although the proposed BMPs are anticipated to provide effective treatment for more than 10 -years, their life will depend on the quality of water draining to them and how well these areas are maintained. BMP maintenance and replacement should be conducted as required to ensure that their character and function are in substantial conformance with the original design. Approximate anticipated average annual costs are summarized below to assist the Owner(s) in budgeting for BMP inspection and maintenance activities. The costs reported are predicated on these activities being conducted while performing other routine maintenance which would ordinarily be performed on site.
Approximate Average Annual Inspection and Maintenance Costs Inspections and Associated Paperwork $1,500
Stenciling Inlets $60
Sediment Removal/Erosion Repair $3,000
Bioretention Area Replacement $2,200
JOB NO. 20109009
109009_SWLID.docx | P a g e 8
APPENDIX A
POST DEVELOPMENT EXHIBIT
JOE RODOTA TRAIL
NORTH WRIGHT ROAD
LOT 1 LOT 2
SYMBOLS & LEGENDEXISTINGPROPOSEDIRON PIPECENTERLINE MONUMENTGATE VALVECHECK VALVEBACKFLOW PREVENTION DEVICEFIRE DEPARTMENT CONNECTIONFIRE HYDRANTPOST INDICATOR VALVESTREET SIGNSTREET LIGHTTREEPROPERTY LINEEASEMENTCENTERLINEGRADE BREAKFLOW LINEFENCESTORM DRAINWATERUNDERGROUND GAS LINEASPHALTCONCRETE
ABBREVIATIONSAC ASPHALT CONCRETEAPN ASSESSOR'S PARCEL NUMBERBFP BACKFLOW PREVENTION DEVICEBLRD BOLLARDBLDG BUILDINGCB CATCH BASINCONC CONCRETEDW DRIVEWAYEP EDGE OF PAVEMENTE ELECTRICFF FINISHED FLOORFG FINISHED GRADEG GASGM GAS METERGI GRATE INLETID INSIDE DIAMETER
INV INVERT - BOTTOM INSIDE OF PIPEIP IRON PIPEL LENGTHOH OVERHEADPG&E PACIFIC GAS & ELECTRICS SLOPESS SANITARY SEWERSSCO SANITARY SEWER CLEAN OUTSSMH SANITARY SEWER MANHOLESD STORM DRAINSDMH STORM DRAIN MANHOLESTLT STREETLIGHTT TELEPHONETB TOP OF BOXTC TOP FACE OF CURBTG TOP OF GRATETYP TYPICALUB UTILITY BOXW WATERWM WATER METER DRAINAGE AREA SUMMARYAREA #C-FACTORSQUARE FO E 10.91,800 20.91,400 30.753,400 40.751,600 50.755,000 60.910,200 70.919,300
LANNERSPURVEYORS / SNGINEERS / E
LEGENDSTORM WATERTREATMENT AREANEW INTERCEPTOR TREETHE PROJECT GEOTECHNICAL ENGINEER REPORTS THAT GROUND WATER WASENCOUNTERED AT THE TIME OF THEIR SUBSURFACE EXPLORATION APPROXIMATELY7-FEET BELOW THE EXISTING GROUND SURFACE.
THE PROJECT GEOTECHNICAL ENGINEER REPORTS THAT SURFACE SOILS ARETYPICALLY OF MODERATE TO HIGH EXPANSION POTENTIAL. THESE SOILS ARETYPICALLY CLASSIFIED AS LYING IN HYDROLOGIC SOIL GROUP "D" HAVING ANINFILTRATION RATE OF APPROXIMATELY 0.05 IN/HR.
A CURVE NUMBER OF 95 HAS CONSERVATIVELY ASSUMED AND USED FORCALCULATIONS FOR MOST AREAS.
NOTES:
JOB NO. 20109009
109009_SWLID.docx | P a g e 9
APPENDIX B
VOLUME CAPTURE CALCULATIONS
BIOSWALE MEDIA MIX MATERIAL DATA SHEET
STORM WATER CALCULATOR
Project Name: Mean Seasonal Precipitation (MSP) of Project Site: 30.00 (inches) Address/Location: K=MSP/30 K= 1.00
Designer:
Date: Impervious area - pre development: ft2
Impervious area - post development: ft2
BMP ID: Tributary
Area (ft2.)
Runoff
Reduction
Measures
(Y/N)
Percent
Achieved
Required
VHydromod
(ft3)
Achieved
(ft3)
Required
Q
Treatment
(cfs)
Achieved
(ft3)
Required
Vdelta (ft3)
Achieved
(ft3)
1 1 1,800 No 104.8 84.5280 88.5600
2 2 1,400 No 103.5 65.7440 68.0400
3 3 3,400 No 132.5 159.6640 211.5000
4 4 1,600 No 119.8 75.1360 90.0000
5 5 5,000 No 123.5 167.6000 207.0000
6 6 10,200 Yes 105.3 422.6400 445.2000
7 7 19,300 Yes 100.5 878.1520 882.5280
8 9
10 11
12 13
14 15
16 17
18 19
20 21
22 23
24 25
26 27
28 29
30 Hydromod Volume Capture Priority 3: P3-04 Roadside Bioretention - Curb Opening Hydromod Volume Capture Priority 3: P3-07 Vegetated Swale Hydromod Volume Capture Priority 3: P3-07 Vegetated Swale Hydromod Volume Capture Priority 2: P2-04 Roadside Bioretention - Curb Opening Hydromod Volume Capture Priority 2: P2-02 Roadside Bioretention - Flush Design Hydromod Volume Capture Priority 2: P2-02 Roadside Bioretention - Flush Design Hydromod Volume Capture Priority 3: P3-07 Vegetated Swale Tributary Area Requirements
BMP Design Results
Hydromodification
Control Flow Base Treatment Delta Volume Capture
Type of Requirement Met Type of BMP Design
BKF Engineers
Delta Volume & Treatment12/20/2018 0.0
21,000.0
Summary of Saved BMP Results:
LID BMP Summary Page & Site Global Values
Project Information: Site Information:
Based upon the pre and post development
impervious area, the post construction BMP
requirement is:
Elm Tree Station
874 North Wright Rd
klhj
Release 8 Draft Rev. 5
12/20/2018
STORM WATER CALCULATOR
BMP Tributary Parameters Project Name:
BMP ID:
BMP Design Criteria:
Type of BMP Design:
BMP's Physical Tributary Area: 1,800.0 ft2
Description/Notes:
Hydromodification Requirement: 100% Volume Capture; VHYDROMOD VHYDROMOD = 84.53 ft3 Post development hydrologic soil type within tributary area:
Post development ground cover description:
CNPOST :
User Composite post development CN: 95.0
BMP Sizing Tool: Hydromodification Requirement Percent of Goal Achieved = 104.77 % Porosity: 0.60
Depth below perforated pipe if present: 1.80 ft Depth: 0.00 ft Width: 0.00 ft Width: 0.00 ft
Length: 0.00 ft Length: 0.00 ft
Area: 82.00 ft2 Area: 0.00 ft2
D: 0 - 0.05 in/hr infiltration (transmission) rate
Urban districts - Commercial and business
BMP Volume
Below Ground
Ponded Water
Above
Ground
Elm Tree Station
1 Delta Volume & Treatment
Priority 2: P2-02 Roadside Bioretention - Flush Design Release 8 Rev. 5
12/20/2018
STORM WATER CALCULATOR
BMP Tributary Parameters Project Name:
BMP ID:
BMP Design Criteria:
Type of BMP Design:
BMP's Physical Tributary Area: 1,400.0 ft2
Description/Notes:
Hydromodification Requirement: 100% Volume Capture; VHYDROMOD VHYDROMOD = 65.74 ft3 Post development hydrologic soil type within tributary area:
Post development ground cover description:
CNPOST :
User Composite post development CN: 95.0
BMP Sizing Tool: Hydromodification Requirement Percent of Goal Achieved = 103.49 % Porosity: 0.60
Depth below perforated pipe if present: 1.80 ft Depth: 0.00 ft Width: 0.00 ft Width: 0.00 ft
Length: 0.00 ft Length: 0.00 ft
Area: 63.00 ft2 Area: 0.00 ft2
D: 0 - 0.05 in/hr infiltration (transmission) rate
Urban districts - Commercial and business
BMP Volume
Below Ground
Ponded Water
Above
Ground
Elm Tree Station
2 Delta Volume & Treatment
Priority 2: P2-02 Roadside Bioretention - Flush Design Release 8 Rev. 5
12/20/2018
STORM WATER CALCULATOR
BMP Tributary Parameters Project Name:
BMP ID:
BMP Design Criteria:
Type of BMP Design:
BMP's Physical Tributary Area: 3,400.0 ft2
Description/Notes:
Hydromodification Requirement: 100% Volume Capture; VHYDROMOD VHYDROMOD = 159.66 ft3 Post development hydrologic soil type within tributary area:
Post development ground cover description:
CNPOST :
User Composite post development CN: 95.0
BMP Sizing Tool: Hydromodification Requirement Percent of Goal Achieved = 132.47 % Porosity: 0.30
Depth below perforated pipe if present: 3.00 ft Depth: 0.00 ft Width: 0.00 ft Width: 0.00 ft
Length: 0.00 ft Length: 0.00 ft
Area: 235.00 ft2 Area: 0.00 ft2
D: 0 - 0.05 in/hr infiltration (transmission) rate
Urban districts - Commercial and business
BMP Volume
Below Ground
Ponded Water
Above
Ground
Elm Tree Station
3 Delta Volume & Treatment
Priority 3: P3-07 Vegetated Swale
Release 8 Rev. 5
12/20/2018
STORM WATER CALCULATOR
BMP Tributary Parameters Project Name:
BMP ID:
BMP Design Criteria:
Type of BMP Design:
BMP's Physical Tributary Area: 1,600.0 ft2
Description/Notes:
Hydromodification Requirement: 100% Volume Capture; VHYDROMOD VHYDROMOD = 75.14 ft3 Post development hydrologic soil type within tributary area:
Post development ground cover description:
CNPOST :
User Composite post development CN: 95.0
BMP Sizing Tool: Hydromodification Requirement Percent of Goal Achieved = 119.78 % Porosity: 0.30
Depth below perforated pipe if present: 3.00 ft Depth: 0.00 ft Width: 0.00 ft Width: 0.00 ft
Length: 0.00 ft Length: 0.00 ft
Area: 100.00 ft2 Area: 0.00 ft2
D: 0 - 0.05 in/hr infiltration (transmission) rate
Urban districts - Commercial and business
BMP Volume
Below Ground
Ponded Water
Above
Ground
Elm Tree Station
4 Delta Volume & Treatment
Priority 3: P3-07 Vegetated Swale
Release 8 Rev. 5
12/20/2018
STORM WATER CALCULATOR
BMP Tributary Parameters Project Name:
BMP ID:
BMP Design Criteria:
Type of BMP Design:
BMP's Physical Tributary Area: 5,000.0 ft2
Description/Notes:
Hydromodification Requirement: 100% Volume Capture; VHYDROMOD VHYDROMOD = 167.60 ft3 Post development hydrologic soil type within tributary area:
Post development ground cover description:
CNPOST :
User Composite post development CN: 92.0
BMP Sizing Tool: Hydromodification Requirement Percent of Goal Achieved = 123.51 % Porosity: 0.30
Depth below perforated pipe if present: 3.00 ft Depth: 0.00 ft Width: 0.00 ft Width: 0.00 ft
Length: 0.00 ft Length: 0.00 ft
Area: 230.00 ft2 Area: 0.00 ft2
D: 0 - 0.05 in/hr infiltration (transmission) rate
Urban districts - Commercial and business
BMP Volume
Below Ground
Ponded Water
Above
Ground
Elm Tree Station
5 Delta Volume & Treatment
Priority 3: P3-07 Vegetated Swale
Release 8 Rev. 5
12/20/2018
STORM WATER CALCULATOR
BMP Tributary Parameters Project Name:
BMP ID:
BMP Design Criteria:
Type of BMP Design:
BMP's Physical Tributary Area: 10,200.0 ft2
Description/Notes:
Runoff Reduction Measures Resulting reduced Tributary Area used for BMP sizing = 9,000.0 ft2 Total Runoff Reduction Measures = 1,200.0 ft2
Interceptor Trees
Number of new interceptor Evergreen Trees : 6 Total Number of New trees in BMP Tributary Area: 6 Number of new interceptor Deciduous Trees : 0
Square footage of qualifying existing tree canopy: 0.0 ft2 Disconnected Roof Drains
Select disconnection condition:
Disconnected Roof Drains Method 1 Disconnected Roof Drains Method 2 Roof area of disconnected downspouts: 0 ft2 Percent of rooftop area: 0 % Select Density: 1 Units per Acre
Paved Area Disconnection
Paved Area Type:
Alternatively designed paved area: 0.0 ft2
Area draining to a Buffer Strip or Bovine Terrace: 0.0 ft2 Hydromodification Requirement: 100% Volume Capture; VHYDROMOD VHYDROMOD = 422.64 ft3 Post development hydrologic soil type within tributary area:
Post development ground cover description:
CNPOST :
User Composite post development CN: 95.0
BMP Sizing Tool: Hydromodification Requirement Percent of Goal Achieved = 105.34 % Porosity: 0.60
Depth below perforated pipe if present: 3.50 ft Depth: 0.00 ft Width: 0.00 ft Width: 0.00 ft
Length: 0.00 ft Length: 0.00 ft
Area: 212.00 ft2 Area: 0.00 ft2
Select paved area type
Buffer Strips & Bovine Terraces
D: 0 - 0.05 in/hr infiltration (transmission) rate
Urban districts - Commercial and business
BMP Volume
Below Ground
Ponded
Water Above
Ground
Elm Tree Station
6 Delta Volume & Treatment
Priority 2: P2-04 Roadside Bioretention - Curb Opening Select disconnection condition
Release 8 Rev. 5
12/20/2018
STORM WATER CALCULATOR
BMP Tributary Parameters Project Name:
BMP ID:
BMP Design Criteria:
Type of BMP Design:
BMP's Physical Tributary Area: 19,300.0 ft2
Description/Notes:
Runoff Reduction Measures Resulting reduced Tributary Area used for BMP sizing = 18,700.0 ft2 Total Runoff Reduction Measures = 600.0 ft2
Interceptor Trees
Number of new interceptor Evergreen Trees : 3 Total Number of New trees in BMP Tributary Area: 3 Number of new interceptor Deciduous Trees : 0
Square footage of qualifying existing tree canopy: 0.0 ft2 Disconnected Roof Drains
Select disconnection condition:
Disconnected Roof Drains Method 1 Disconnected Roof Drains Method 2 Roof area of disconnected downspouts: 0 ft2 Percent of rooftop area: 0 % Select Density: 1 Units per Acre
Paved Area Disconnection
Paved Area Type:
Alternatively designed paved area: 0.0 ft2
Area draining to a Buffer Strip or Bovine Terrace: 0.0 ft2 Hydromodification Requirement: 100% Volume Capture; VHYDROMOD VHYDROMOD = 878.15 ft3 Post development hydrologic soil type within tributary area:
Post development ground cover description:
CNPOST :
User Composite post development CN: 95.0
BMP Sizing Tool: Hydromodification Requirement Percent of Goal Achieved = 100.50 % Porosity: 0.60
Depth below perforated pipe if present: 1.16 ft Depth: 0.00 ft Width: 0.00 ft Width: 0.00 ft
Length: 0.00 ft Length: 0.00 ft
Area: 1,268.00 ft2 Area: 0.00 ft2
Select paved area type
Buffer Strips & Bovine Terraces
D: 0 - 0.05 in/hr infiltration (transmission) rate
Urban districts - Commercial and business
BMP Volume
Below Ground
Ponded
Water Above
Ground
Elm Tree Station
7 Delta Volume & Treatment
Priority 3: P3-04 Roadside Bioretention - Curb Opening Select disconnection condition
Release 8 Rev. 5
12/20/2018
JOB NO. 20109009
109009_SWLID.docx | P a g e 10
APPENDIX C
DETERMINATION WORKSHEET
SUSMP SUBMITTAL GUIDE CHECKLIST
BMP SELECTION TABLES
JOB NO. 20109009
109009_SWLID.docx | P a g e 11
APPENDIX D
BIORETENTION AREA FACT SHEET
VEGETATED SWALE FACT SHEET
JOB NO. 20109009
109009_SWLID.docx | P a g e 12
APPENDIX E
SAMPLE OPERATION AND MAINTENANCE INSPECTION CHECKLISTS
JOB NO. 20109009
109009_SWLID.docx | P a g e 13
APPENDIX F
MAINTENANCE DECLARATION