Attachment 6 - Civil Submittal — Santa Rosa City Council, May 23, 2023

RECEIVED 12-21-22

CLEVE GURNEY
Attachment 6

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INTRODUCTION

The Steel Lane Apartments site is located at 1650 West Steele Lane in the City of Santa Rosa. The project consists of 0.98 acres and is contained within one assessor’s parcels, APN 041-042-012. The site is currently vacant and consists of native grasses and a handful of trees. There are no existing drainage features onsite.

The project is proposed by Stagecoach Development Company, Inc, as a single, non- phased project. The project proposes the construction of 3 separate apartment buildings consisting of a total of 36 rental units, a leasing office and an onsite laundry facility. The proposed improvements also include site amenities and tenant parking on the property. A new storm drain system will be constructed with this project that will collect overland flow and convey it through an underground pipe network that will connect into the existing 15” storm drain system within Meadowbrook Court.

BRIEF SUMMARY

The following hydrology and hydraulic calculations show that the proposed storm drain system that drains to Meadowbrook Court has the capacity to accept runoff from the proposed development. For more information, see the conclusions section at the end of this report.

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HYDROLOGY

The following hydrology calculations were calculated using variables of the Incremental Rational Method (IRM). The variables used in the analysis were obtained from Sonoma Water’s Flood Management Design Manual (FMDM). Runoff coefficients (C) were based on FMDM Appendix C, Table C-1, and reflect the existing and ultimate land use of the property and the surrounding areas. Precipitation data was taken from NOAA Atlas 14, which provides site specific rainfall depths and intensities for various storm events.

The initial time of concentrations are set at 7 minutes per the proposed land use. Due to the size of the project, the storm drain system will be designed for the 10-year event. A final drainage report will be prepared with the construction permit drawings to show the 100-year storm will not threaten the finish floors of the proposed buildings.

In order to demonstrate to the City of Santa Rosa that the proposed storm drain system is adequately sizes and has the capacity to accept runoff from the proposed development, an analysis of the site hydrology has been prepared. The hydrology calculations were performed using the Hydraflow Storm Sewers Extension for Civil 3D developed and marketed by Autodesk. This software suite calculates the peak flow of a catchment by simultaneously calculating a basin’s hydrologic characteristics and hydraulic capacity.

This differs from the traditional approach of calculating the hydrology independent of any hydraulic or backwater effects. In some situations, this sort of analysis appears to lengthen the time of concentration of a basin due to the velocity in the pipes of the system being calculated under backwater conditions rather than under full-flow/ gravity depth velocities. Such an approach is slightly less conservative but is probably more realistic.

Further explanation of the implications of this approach is discussed in the Hydraulic Section of this submittal.

A hydrology map has been prepared and submitted with this package to delineate the proposed hydrologic conditions. The hydrology map defines the limits of the basins tributary to the points of connection to the existing storm drain system within Meadowbrook Court. This map is used as the basis for determining the peak runoff quantities discharged into the system, as determined by existing, proposed, and future land uses. Treatment facilities associated with the Storm Water Low Impact Development Submittal are assumed to be full during the design storm, and any beneficial effects from these features have been ignored to be conservative.

Table C-1. Runoff Coefficients ( Cs) (Incremental Rational Method) Land Use Lot Size Impervious Average Slope (%)
(acres) Fraction
Soil Type A
Residential1
Rural 0.03 0.24 0.28 0.34 0.38
Very low density 2 0.11 0.29 0.34 0.38 0.42
1 0.24 0.38 0.42 0.46 0.49
Low density 1/2 0.32 0.43 0.47 0.50 0.53
1/3 0.41 0.50 0.53 0.56 0.58
Medium-low density 1/4 0.49 0.55 0.58 0.60 0.62
Medium density 1/8 0.70 0.70 0.71 0.73 0.74
Medium-high density 1/18 1 0.90 0.90 0.90 0.90
Business, commercial, etc. 1 0.90 0.90 0.90 0.90
General industrial 1 0.90 0.90 0.90 0.90
Parks and recreation 0.05 0.25 0.25 0.30 0.35
Ag and open space 0.02 0.23 0.23 0.28 0.33
Soil Type B
Residential
1 Rural 0.03 0.28 0.33 0.39 0.43
Very low density 2 0.11 0.34 0.38 0.43 0.47
1 0.24 0.42 0.45 0.50 0.53
Low density 1/2 0.32 0.47 0.50 0.54 0.57
1/3 0.41 0.53 0.56 0.59 0.61
Medium-low density 1/4 0.49 0.58 0.60 0.63 0.65
Medium density 1/8 0.70 0.71 0.73 0.74 0.76
Medium-high density 1/18 1 0.90 0.90 0.90 0.90
Business, commercial, etc. 1 0.90 0.90 0.90 0.90
General industrial 1 0.90 0.90 0.90 0.90
Parks and recreation 0.05 0.25 0.30 0.34 0.40
Ag and open space 0.02 0.23 0.28 0.33 0.38
Soil Type C
Residential
1 Rural 0.03 0.33 0.38 0.43 0.47
Very low density 2 0.11 0.38 0.42 0.47 0.51
1 0.24 0.45 0.49 0.53 0.57
Low density 1/2 0.32 0.50 0.53 0.57 0.60
0-2 >2-6 >6-12 >12
3 Land Use Lot Size Impervious Average Slope (%)
(acres) Fraction
1/3 0.41 0.56 0.59 0.62 0.64
Medium-low density 1/4 0.49 0.60 0.63 0.65 0.68
Medium density 1/8 0.70 0.73 0.74 0.76 0.77
Medium-high density 1/18 1 0.90 0.90 0.90 0.90
Business, commercial, etc. 1 0.90 0.90 0.90 0.90
General industrial 1 0.90 0.90 0.90 0.90
Parks and recreation 0.05 0.34 0.39 0.44 0.48
Ag and open space 0.02 0.33 0.38 0.43 0.47
Soil Type D
Residential1
Rural 0.03 0.38 0.43 0.48 0.52
Very low density 2 0.11 0.42 0.47 0.52 0.55
1 0.24 0.49 0.53 0.57 0.60
Low density 1/2 0.32 0.54 0.57 0.61 0.63
1/3 0.41 0.59 0.62 0.65 0.67
Medium-low density 1/4 0.49 0.63 0.65 0.68 0.70
Medium density 1/8 0.70 0.74 0.76 0.77 0.78
Medium-high density 1/18 1 0.90 0.90 0.90 0.90
Business, commercial 1 0.90 0.90 0.90 0.90
General industrial 1 0.90 0.90 0.90 0.90
Parks and recreation 0.05 0.39 0.44 0.49 0.53
Ag and open space 0.02 0.38 0.42 0.48 0.52
0-2 >2-6 >6-12 >12
1 Percent impervious values are based on analysis conducted by ESA for Sonoma County Water Agency (Sonoma Water) in 2014, using a sample of existing developed areas. 2 For residential areas, composite C values were developed as follows: C values for soil type from Los Angeles County Hydrology Manual (1991) were modified for slope using the vegetated areas curve from Plate B-1 of SCWA (1983) for pervious areas within a given slope range and a C of 0.90 for all impervious areas.

Source: Approach adapted from McCuen 1989
4 Soil Map—Sonoma County, California
(1650 West Steele Lane)
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
3/29/2019

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4256810 4256820 4256830 4256840 4256850 4256860 4256870 4256880 4256810 4256820 4256830 4256840 4256850 4256860 4256870 4256880 523130 523140 523150 523160 523170 523180 523190 523200 523210 523220 523230 523240 523130 523140 523150 523160 523170 523180 523190 523200 523210 523220 523230 523240 38° 27' 35'' N
122° 44' 5'' W
38° 27' 35'' N
122° 44' 0'' W
38° 27' 33'' N
122° 44' 5'' W
38° 27' 33'' N
122° 44' 0'' W
N
Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 10N WGS84 0 25 50 100 150
Feet
0 5 10 20 30
Meters
Map Scale: 1:556 if printed on A landscape (11" x 8.5") sheet.

Soil Map may not be valid at this scale.

MAP LEGEND MAP INFORMATION
Area of Interest (AOI)
Area of Interest (AOI)
Soils
Soil Map Unit Polygons
Soil Map Unit Lines
Soil Map Unit Points
Special Point Features
Blowout
Borrow Pit
Clay Spot
Closed Depression
Gravel Pit
Gravelly Spot
Landfill
Lava Flow
Marsh or swamp
Mine or Quarry
Miscellaneous Water
Perennial Water
Rock Outcrop
Saline Spot
Sandy Spot
Severely Eroded Spot
Sinkhole
Slide or Slip
Sodic Spot
Spoil Area
Stony Spot
Very Stony Spot
Wet Spot
Other
Special Line Features
Water Features
Streams and Canals
Transportation
Rails
Interstate Highways
US Routes
Major Roads
Local Roads
Background
Aerial Photography
The soil surveys that comprise your AOI were mapped at
1:20,000.

Warning: Soil Map may not be valid at this scale.

Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale.

Please rely on the bar scale on each map sheet for map
measurements.

Source of Map: Natural Resources Conservation Service
Web Soil Survey URL:

Coordinate System: Web Mercator (EPSG:3857)
Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required.

This product is generated from the USDA-NRCS certified data as of the version date(s) listed below.

Soil Survey Area: Sonoma County, California
Survey Area Data: Version 12, Sep 13, 2018
Soil map units are labeled (as space allows) for map scales 1:50,000 or larger.

Date(s) aerial images were photographed: Jul 1, 2018—Jul 31, 2018
The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident.

Soil Map—Sonoma County, California
(1650 West Steele Lane)
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
3/29/2019

Page 2 of 3 ends

Map Unit Legend
Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI ZaA Zamora silty clay loam, moist,
0 to 2 percent slopes, MLRA
14 1.2 100.0%
Totals for Area of Interest 1.2 100.0%
Soil Map—Sonoma County, California 1650 West Steele Lane Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
3/29/2019

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Sonoma County, California
ZaA—Zamora silty clay loam, moist, 0 to 2 percent slopes, MLRA 14
Map Unit Setting
National map unit symbol: 2xcbw
Elevation: 20 to 260 feet
Mean annual precipitation: 27 to 43 inches
Mean annual air temperature: 58 to 59 degrees F
Frost-free period: 288 to 325 days
Farmland classification: Prime farmland if irrigated
Map Unit Composition
Zamora and similar soils: 85 percent
Minor components: 15 percent
Estimates are based on observations, descriptions, and transects of the mapunit.

Description of Zamora
Setting
Landform: Stream terraces, alluvial fans
Landform position (two-dimensional): Toeslope
Landform position (three-dimensional): Tread
Down-slope shape: Linear
Across-slope shape: Linear
Parent material: Alluvium derived from volcanic and sedimentary rock
Typical profile
A1 - 0 to 5 inches: silty clay loam
A2 - 5 to 17 inches: clay loam
A3 - 17 to 29 inches: clay loam
Bt1 - 29 to 41 inches: clay loam
Bt2 - 41 to 55 inches: sandy clay loam
Bt3 - 55 to 60 inches: gravelly clay
Properties and qualities
Slope: 0 to 2 percent
Depth to restrictive feature: More than 80 inches
Natural drainage class: Well drained
Runoff class: Medium
Capacity of the most limiting layer to transmit water (Ksat):

Moderately low to moderately high (0.06 to 0.20 in/hr)
Depth to water table: More than 80 inches
Frequency of flooding: Rare
Frequency of ponding: None
Salinity, maximum in profile: Nonsaline (0.2 to 0.5 mmhos/cm) Available water storage in profile: High (about 10.4 inches) Map Unit Description: Zamora silty clay loam, moist, 0 to 2 percent slopes, MLRA 14--- Sonoma County, California
Southside
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
3/26/2019

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Interpretive groups
Land capability classification (irrigated): 1
Land capability classification (nonirrigated): 3c
Hydrologic Soil Group: C
Hydric soil rating: No
Minor Components
Cole
Percent of map unit: 4 percent
Hydric soil rating: No
Yolo
Percent of map unit: 4 percent
Hydric soil rating: No
Cortina
Percent of map unit: 3 percent
Hydric soil rating: No
Pajaro
Percent of map unit: 3 percent
Hydric soil rating: No
Unnamed
Percent of map unit: 1 percent
Landform: Depressions
Hydric soil rating: Yes
Data Source Information
Soil Survey Area: Sonoma County, California
Survey Area Data: Version 12, Sep 13, 2018
Map Unit Description: Zamora silty clay loam, moist, 0 to 2 percent slopes, MLRA 14--- Sonoma County, California
Southside
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
3/26/2019

Page 2 of 2 ends

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/0/i255/10/11/12/13/14/15/14/16/17/16/14/18/19/i255/33/11/12/21/22/12/19/13/23/i255/131/10/20/133/i255/12/28/16/14/35/17/16/12/28/i255/14/19/i255/16/27/14/28/i255/16/17/108/36/12/i255/17/11/12/i255/108/17/28/12/29/i255/18/19/i255/33/11/12/21/22/12/19/13/23/i255/17/19/17/36/23/28/14/28/i255/18/33/i255/15/17/11/16/14/17/36/i255/29/22/11/17/16/14/18/19/i255/28/12/11/14/12/28/i255/131/10/24/25/133/30 /116/22/35/108/12/11/28/i255/14/19/i255/15/17/11/12/19/16/27/12/28/14/28/i255/17/11/12/i255/10/20/i255/12/28/16/14/35/17/16/12/28/i255/17/16/i255/36/18/31/12/11/i255/17/19/29/i255/22/15/15/12/11/i255/108/18/22/19/29/28/i255/18/33/i255/16/27/12/i255/42/1/134/i255/13/18/19/33/14/29/12/19/13/12/i255/14/19/16/12/11/26/17/36/30/i255/110/27/12/i255/15/11/18/108/17/108/14/36/14/16/23/i255/16/27/17/16/i255/15/11/12/13/14/15/14/16/17/16/14/18/19/i255/33/11/12/21/22/12/19/13/23/i255/12/28/16/14/35/17/16/12/28/i255/131/33/18/11/i255/17 /32/14/26/12/19/i255/29/22/11/17/16/14/18/19/i255/17/19/29/i255/17/26/12/11/17/32/12/i255/11/12/13/22/11/11/12/19/13/12/i255/14/19/16/12/11/26/17/36/133/i255/31/14/36/36/i255/108/12/i255/32/11/12/17/16/12/11/i255/16/27/17/19/i255/16/27/12/i255/22/15/15/12/11/i255/108/18/22/19/29/i255/131/18/11/i255/36/12/28/28/i255/16/27/17/19/i255/16/27/12/i255/36/18/31/12/11/i255/108/18/22/19/29/133/i255/14/28/i255/41/134/30/i255/91/28/16/14/35/17/16/12/28/i255/17/16/i255/22/15/15/12/11/i255/108/18/22/19/29/28/i255/17/11/12/i255/19/18/16 /13/27/12/13/111/12/29/i255/17/32/17/14/19/28/16/i255/15/11/18/108/17/108/36/12/i255/35/17/135/14/35/22/35/i255/15/11/12/13/14/15/14/16/17/16/14/18/19/i255/131/10/9/10/133/i255/12/28/16/14/35/17/16/12/28/i255/17/19/29/i255/35/17/23/i255/108/12/i255/27/14/32/27/12/11/i255/16/27/17/19/i255/13/22/11/11/12/19/16/36/23/i255/26/17/36/14/29/i255/10/9/10/i255/26/17/36/22/12/28/30 /10/36/12/17/28/12/i255/11/12/33/12/11/i255/16/18/i255/116/117/8/8/i255/8/16/36/17/28/i255/0/40/i255/29/18/13/22/35/12/19/16/i255/33/18/11/i255/35/18/11/12/i255/14/19/33/18/11/35/17/16/14/18/19/30 /114/17/13/111/i255/16/18/i255/110/18/15
/96/99/i255/84/64/53/122/126/65/69/53/52
i = 7.29x‐0.514
i = 8.61tc‐0.512
i = 10.75tc‐0.513
0 0.5
1 1.5
2 2.5
3 3.5
4 4.5
5 0 1 02 03 04 05 06 07 0
Intensity,i (in/hr)
Duration, tc (min)
STEELE LANE APARTMENTS ‐ Rainfall Instensity vs Duration 10‐Year 25‐Year 100‐Year 10‐Year IDF Curve 25‐Year IDF Curve 100‐Year IDF Curve

S:\SDSK\PROJ\19-107\Dwg\HnH\PRELIMINARY ANALYSIS\WSL-PRELIM DRAINAGE ANALYSIS.docx

HYDRAULICS

Basis

As was mentioned in the preceding section, the hydraulics of the project were analyzed simultaneously with the hydrology of the project. Therefore, the hydraulics and hydrology are more interdependent than had they been analyzed separately.

System Analysis

The proposed onsite storm drain system has two connection points to the storm drain system within Meadowbrook Court. The first connection is the proposed 15” storm drain within the projects drive aisle to the existing 15” storm drain within the northbound lane of Meadowbrook Court. The second connection point is the proposed 15” storm drain connecting to the existing 21” storm drain crossing Meadowbrook Court at the northwest corner of the project site. The system was analyzed as a model with a single outfall at the existing catch basin across Meadowbrook Court from the second connection point.

The Autodesk software automatically computes minor losses at junctions and inlets based on data adapted from FHWA HEC No. 22. The backwater analysis of the storm drain systems is based on this method. Also, since the proposed storm drain system consists of HDPE plastic pipes, the Manning’s n for the pipes has been set at 0.012 per FMDM Table D.2-4.

Starting HGL

Sonoma Water does not have reliable and/or up to date hydraulic data of the existing storm drain system within Meadowbrook Court therefore the flow line of the gutter pan at the second connection was used as the starting 10-year HGL elevation. The 10-year starting HGL was set to an elevation of 133.60. This was done as a conservative measure to assure that the existing storm drain system within Meadowbrook Court is analyzed as flowing at maximum capacity and prove that the proposed storm drain system can convey the runoff from the proposed improvements. The analysis was accomplished by backwatering against the 10-year hydraulic grade line as previously mentioned.

S:\SDSK\PROJ\19-107\Dwg\HnH\PRELIMINARY DRAINAGE ANALYSIS\WSL-PRELIM DRAINAGE ANALYSIS.docx

CONCLUSIONS

Analysis of the proposed storm drain system shows that the system is fully capable of accepting discharge produced by the 10-year storm event from the proposed development. Ponding does not occur at any of the proposed low points/inlets throughout the project site demonstrating that the proposed system is adequately sized.

S:\SDSK\PROJ\19-107\Dwg\HnH\PRELIMINARY DRAINAGE ANALYSIS\WSL-PRELIM DRAINAGE ANALYSIS.docx

Exhibits

VITREOUS CHINATOILETGABRIELLEK-3322
VITREOUS CHINATOILETGABRIELLEK-3322
VITREOUS CHINATOILETGABRIELLEK-3322
VITREOUS CHINATOILETGABRIELLEK-3322
VITREOUS CHINATOILETGABRIELLEK-3322
VITREOUS CHINATOILETGABRIELLEK-3322
VITREOUS CHINATOILETSSAN MARTINEK-3435
VITREOUS CHINATOILETSSAN MARTINEK-3435
VITREOUS CHINATOILETGABRIELLEK-3322
VITREOUS CHINATOILETGABRIELLEK-3322
VITREOUS CHINATOILETGABRIELLEK-3322
SD
C
OHUX

Initial Storm Water Low Impact Development Submittal

S:\SDSK\PROJ\19-107\Dwg\SUSMP\ISWLIDS\WSL-ISWLIDS.docx

CONTENTS

1 INTRODUCTION

2 PROJECT DESCRIPTION

3 POLLUTION PREVENTION MEASURES

4 TYPES OF BMP’S SELECTED TO MITIGATE POLLUTANTS

AND PROVIDE VOLUME CAPTURE

5 RESPONSIBILITY FOR BMP MAINTENANCE

ATTACHMENTS

Determination Worksheet
Initial SW LID Hydrology Map
BMP Details
Stormwater Calculator Spreadsheets
Soils Analysis
BMP Selection Tables
Maintenance Checklists
Standard Maintenance/Monitoring Agreement

Initial Storm Water Low Impact Development Submittal

S:\SDSK\PROJ\19-107\Dwg\SUSMP\ISWLIDS\WSL-ISWLIDS.docx

1 INTRODUCTION

The Steele Lane Apartments project site is within the permit boundary of the recently adopted National Pollutant Discharge Elimination System (NPDES) Municipal Separate Storm Sewer System (MS4) Storm Water Permit which regulates discharges into the watershed with the intent to reduce storm water pollution and protect the water quality of our local creeks and waterways and continue to promote groundwater recharge. The City of Santa Rosa and the County of Sonoma have adopted the Storm Water Low Impact Development (LID) Technical Design Manual. This Initial Storm Water Low Impact Development Submittal (ISWLIDS) was developed to show compliance with its requirements.

Standard Urban Storm Water Mitigation Plan (SUSMP) requirements are part of the Storm Water Management Plan that is an enforceable part of the reissued municipal storm water NPDES permit for the City of Santa Rosa, the County of Sonoma and Sonoma Water. Satisfying the SUSMP and the NPDES Permit will require meeting the following goals to the maximum extent practicable:

1. Prevent pollutants generated at the site from leaving the site.

2. Prevent increases in Storm Water runoff for 1.0 inch of rainfall over a 24 hour period.

3. Strive to maximize the amount of land left in a natural undisturbed condition.

This Initial SW LID Submittal will provide the following information:

• Project Description

• Pollution Prevention Measures

• Types of BMP selected to mitigate pollutants and provide volume capture.

• Responsibility for BMP maintenance

• Location and design of BMP (on project drawings)

Initial Storm Water Low Impact Development Submittal

S:\SDSK\PROJ\19-107\Dwg\SUSMP\ISWLIDS\WSL-ISWLIDS.docx

2 PROJECT DESCRIPTION

The Steele Lane Apartments project site is located at 1650 West Steele Lane, within the City of Santa Rosa.

The property contains an area of 0.98 acres and is contained within one assessor parcel, APN 041-042-012. Additionally, the project proposes 0.09 acres of improvements to the frontage along Meadowbrook Court and West Steele Lane, bringing the total project area to 1.07 acres. The existing site appears to be vacant, containing a handful of trees and some native grasses.

The project is proposed by Stagecoach Development Company, Inc. as a single, non- phased development. The project proposes to construct 36 rental units, a leasing office, and onsite laundry facilities within three separate three story buildings. The project will also feature a parking lot with stacked parking structure and some site amenities.

The project will collect overland flow and route it to a series of proposed stormwater treatment facilities before entering the underground drainage system. These features will be constructed over aggregate layers where stormwater will be retained. This pre- treatment design feature shall not only remove pollutants, but also will reduce the amount of runoff by capturing and infiltrating storm water onsite. The treatment facilities are proposed at various locations throughout the project site, providing treatment for each of the site tributaries. The purpose of these devices and their effect on the quality and quantity of runoff leaving the developed site will be further explained throughout this report.

The project site’s native soil has been classified by the Natural Resources Conservation Service as Clear Lake Clay (CeA) and is in Hydrologic Soil Group D. This is a poorly drained soil with the expected infiltration rate to be less than 0.20 in/hr. Due to the very low expected infiltration rate, the selected LID features will be Priority 2 containing subsurface perforated pipe to prevent surface ponding of storm water. The site soil classification has been confirmed by the geotechnical report prepared for the project. No site specific percolation/infiltration studies have been performed.

The attached plan titled “Initial SW LID Hydrology Map” shows the proposed grading pattern for the project along with the drainage tributary areas and proposed treatment facilities. Treatment facility details showing volume capture designed to meet the 100% volume capture goal can be found in the attachments section of this document.

Initial Storm Water Low Impact Development Submittal

S:\SDSK\PROJ\19-107\Dwg\SUSMP\ISWLIDS\WSL-ISWLIDS.docx

3 POLLUTION PREVENTION MEASURES

A portion of roof drains of the buildings will be disconnected from the storm drain system, allowing storm drainage to surface flow over landscaped areas to a stormwater treatment facility before entering the underground storm drain system.

The project will incorporate a robust Landscape plan including interceptor trees that will be planted throughout the project.

The total tributary area used for volume capture calculations has been reduced by taking credit for these measures.

Initial Storm Water Low Impact Development Submittal

S:\SDSK\PROJ\19-107\Dwg\SUSMP\ISWLIDS\WSL-ISWLIDS.docx

4 TYPES OF BMP’S SELECTED TO MITIGATE POLLUTANTS AND

PROVIDE VOLUME CAPTURE

Best Management Practices (BMP’s) are design features that address the quality and quantity of the storm waters that flow from a development. In most cases, these BMP’s are used to mitigate a development’s impact on the quality of storm water by treating or cleaning the storm water. Some controls have dual treatment control measure capabilities, not only treating, but also containing a required volume of storm water. The project will implement bio-retention beds to mitigate pollutants and provide volume capture for the 85th percentile 24-hour storm. Volume capture is accomplished by incorporating an area for storm water storage beneath the bio-retention beds.

Bio-retention beds have been selected for this project because of their ability to remove pollutants through a variety of natural physical, biological and chemical treatment processes. These BMP’s are considered a Low Impact Development (LID) device for treatment control. They have also been selected because they provide an excellent opportunity for the runoff to settle any suspended solids and remove hydrocarbons, both of which have been identified as pollutants that can degrade the downstream receiving waters of the project. Compared to pipe networks, bio-retention beds with gravel storage areas will reduce runoff from the site and provide ground water recharge. This provides the opportunity to reduce the peak flow in a basin. For this project we have selected aggregate consisting of ¾ inch to 1-1/2 inch structural soil for the storage area. The structural soil has a porosity of 30%. This provides the opportunity to reduce the peak flow in a basin.

The structural soil shall meet standards set forth in the City of Santa Rosa Low Impact Development Design Manual reference document ‘E’ and geotechnical report. The structural soil will also provide an environment for landscaping to thrive as it is composed of angular rocks and fine organics, providing an excellent environment for water infiltration and plant growth.

The widening of the existing sidewalk along West Steele Lane, the new pedestrian ramp at the intersection of West Steele and Meadowbrook, and a small portion of the on-site entry area cannot be captured and treated directly. An existing shallow storm drain runs under the West Steele planter strip between the curb and the sidewalk and maintains ±2 feet of cover throughout the planter strip. This existing shallow storm drain prohibits the construction of roadside bio-retention bed in the West Steele planter strip. Volume capture for the untreated area will be accomplished by oversizing the roadside bio- retention bed (BMP 1) along Meadowbrook Court. A storm water filter insert will be installed in the new storm drain catch basin adjacent to BMP 1. The 1,840 SF of untreated/uncaptured area and the 3,158 SF of the existing Meadowbrook Court pavement offset area are highlighted on the LID exhibit attached.

This project meets the Design Goal by achieving 100% volume capture.

Initial Storm Water Low Impact Development Submittal

S:\SDSK\PROJ\19-107\Dwg\SUSMP\ISWLIDS\WSL-ISWLIDS.docx

5 RESPONSIBILITY FOR BMP MAINTENANCE

All treatment control devices serving the project are located within the project site, or within the right of way of Meadowbrook Court. The property owner will be responsible for the surface and sub-surface oversight and maintenance of the treatment control devices.

Attached is a Draft of the Maintenance Agreement for Monitoring Storm Water BMP Facilities and Declaration of Covenants.

Initial Storm Water Low Impact Development Submittal

S:\SDSK\PROJ\19-107\Dwg\SUSMP\ISWLIDS\WSL-ISWLIDS.docx

ATTACHMENTS

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ŶĐƌŽĂĐŚŵĞŶƚ KƚŚĞƌ

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Print Form
Steele Lane Apartments Stagecoach Development Company, Inc. 1650 West Steele Lane 19 Leona Drive
Santa Rosa / CA / 95403 San Rafael / CA / 94903
(415) 491-4091
Civil Design Consultants, Inc. 2200 Range Avenue, Suite 204 Santa Rosa / CA / 95403 (707)542-4820
✔
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Steele Lane Apartments
✔
✔
✔
✔
✔
✔
✔
ϮϬϭϳ^ƚŽƌŵtĂƚĞƌ>/ĞƚĞƌŵŝŶĂƚŝŽŶtŽƌŬƐŚĞĞƚ
Public

3. Existing impervious surface area: square feet
acres

4. Proposed Land Use(s): (check all that apply)

2. Existing land use(s): (check all that apply)

1. Total Project area: Ɛquare feet
acres
Other
WĂƌƚϰ͗WƌŽũĞĐƚĞƐĐƌŝƉƚŝŽŶ
Commercial Industrial Residential
Description of buildings, significant site features;ĐƌĞĞŬƐ͕ǁĞƚůĂŶĚƐ͕ŚĞƌŝƚĂŐĞƚƌĞĞƐͿ, etc.:

Commercial Industrial Residential Public Other ĞƐĐƌŝƉƚŝŽŶŽĨďƵŝůĚŝŶŐƐ͕ƐŝŐŶŝĨŝĐĂŶƚƐŝƚĞĨĞĂƚƵƌĞƐ;ĐƌĞĞŬƐ͕ǁĞƚůĂŶĚƐ͕ŚĞƌŝƚĂŐĞƚƌĞĞƐͿ͕ĞƚĐ͗͘ Project Name
ϱ. Existing impervious surface area: square feet
acres
WĂŐĞϯ
ϲͬϭͬϮϬϭϳsĞƌƐŝŽŶϴ
Steele Lane Apartments
43,893
✔
The site is currently vacant, containing some trees and native grasses. 0 ✔
The proposed project will create 36 apartment units, a leasing office, and laundry facility within 3 three-story buildings. Additionally, the site will feature a parking lot, stacked parking structure, and some site amenities. 34,027

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 TRIB-1 12,736 Yes 102.9 463.4016 477.0000
2 TRIB-2 6,867 Yes 101.3 267.3083 270.6750
3 TRIB-3 12,460 Yes 101.4 465.9630 472.5000
4 TRIB-4 9,059 Yes 100.9 287.4635 289.9800
5 TRIB-5 2,226 Yes 102.9 72.9786 75.1140
6 TRIB-6 6,439 Yes 101.1 201.5940 203.7630
7 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 2: P2-05 Roadside Bioretention - No Curb AND Gutter Hydromod Volume Capture Priority 2: P2-05 Roadside Bioretention - No Curb AND Gutter Hydromod Volume Capture Priority 2: P2-05 Roadside Bioretention - No Curb AND Gutter Hydromod Volume Capture Priority 2: P2-04 Roadside Bioretention - Curb Opening Hydromod Volume Capture Priority 2: P2-04 Roadside Bioretention - Curb Opening Hydromod Volume Capture Priority 2: P2-04 Roadside Bioretention - Curb Opening Tributary Area Requirements
BMP Design Results
Hydromodification
Control Flow Base Treatment Delta Volume Capture
Type of Requirement Met Type of BMP Design
Matt Lawton
Delta Volume & Treatment11/28/2022 0.0
34,027.0
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:

Steele Lane Apartments
1650 West Steele Lane
klhj
Release 8 Draft Rev. 5
11/28/2022

STORM WATER CALCULATOR
BMP Tributary Parameters Project Name:

BMP ID:

BMP Design Criteria:

Type of BMP Design:

BMP's Physical Tributary Area: 12,736.0 ft2
Description/Notes:

Runoff Reduction Measures Resulting reduced Tributary Area used for BMP sizing = 11,036.0 ft2 Total Runoff Reduction Measures = 1,700.0 ft2
Interceptor Trees
Number of new interceptor Evergreen Trees : 3 Total Number of New trees in BMP Tributary Area: 14 Number of new interceptor Deciduous Trees : 11
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 = 463.40 ft3 Post development hydrologic soil type within tributary area:

Post development ground cover description:

CNPOST : 94
User Composite post development CN: 0.0
BMP Sizing Tool: Hydromodification Requirement Percent of Goal Achieved = 102.93 % Porosity: 0.30
Depth below perforated pipe if present: 2.50 ft Depth: 0.00 ft Width: 0.00 ft Width: 0.00 ft
Length: 0.00 ft Length: 0.00 ft
Area: 636.00 ft2 Area: 0.00 ft2
Select paved area type
Buffer Strips & Bovine Terraces
C: 0.05 - 0.15 in/hr infiltration (transmission) rate
Urban districts - Commercial and business
BMP Volume
Below Ground
Ponded
Water Above
Ground
Steele Lane Apartments
TRIB-1
Delta Volume & Treatment
Priority 2: P2-04 Roadside Bioretention - Curb Opening BMP 1 has been sized with an additional 3,158 SF of existing Meadowbrook Court pavement offset area added to the 9,578 SF area of Tributary 1 for a total 12,736 SF to accommodate the 1,840 SF of untreated/uncaptured area along the West Steele Lane frontage Select disconnection condition
Release 8 Rev. 5
11/28/2022

STORM WATER CALCULATOR
BMP Tributary Parameters Project Name:

BMP ID:

BMP Design Criteria:

Type of BMP Design:

BMP's Physical Tributary Area: 6,867.0 ft2
Description/Notes:

Runoff Reduction Measures Resulting reduced Tributary Area used for BMP sizing = 6,366.0 ft2 Total Runoff Reduction Measures = 501.0 ft2
Interceptor Trees
Number of new interceptor Evergreen Trees : 0 Total Number of New trees in BMP Tributary Area: 5 Number of new interceptor Deciduous Trees : 5
Square footage of qualifying existing tree canopy: 2.0 ft2 Disconnected Roof Drains
Select disconnection condition:

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 = 267.31 ft3 Post development hydrologic soil type within tributary area:

Post development ground cover description:

CNPOST : 94
User Composite post development CN: 0.0
BMP Sizing Tool: Hydromodification Requirement Percent of Goal Achieved = 101.26 % Porosity: 0.30
Depth below perforated pipe if present: 2.25 ft Depth: 0.00 ft Width: 0.00 ft Width: 0.00 ft
Length: 0.00 ft Length: 0.00 ft
Area: 401.00 ft2 Area: 0.00 ft2
Select paved area type
Buffer Strips & Bovine Terraces
C: 0.05 - 0.15 in/hr infiltration (transmission) rate
Urban districts - Commercial and business
BMP Volume
Below Ground
Ponded
Water Above
Ground
Steele Lane Apartments
TRIB-2
Delta Volume & Treatment
Priority 2: P2-04 Roadside Bioretention - Curb Opening Select disconnection condition
Release 8 Rev. 5
10/13/2022

STORM WATER CALCULATOR
BMP Tributary Parameters Project Name:

BMP ID:

BMP Design Criteria:

Type of BMP Design:

BMP's Physical Tributary Area: 12,460.0 ft2
Description/Notes:

Runoff Reduction Measures Resulting reduced Tributary Area used for BMP sizing = 11,096.5 ft2 Total Runoff Reduction Measures = 1,363.5 ft2
Interceptor Trees
Number of new interceptor Evergreen Trees : 2 Total Number of New trees in BMP Tributary Area: 7 Number of new interceptor Deciduous Trees : 5
Square footage of qualifying existing tree canopy: 927.0 ft2 Disconnected Roof Drains
Select disconnection condition:

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 = 465.96 ft3 Post development hydrologic soil type within tributary area:

Post development ground cover description:

CNPOST : 94
User Composite post development CN: 0.0
BMP Sizing Tool: Hydromodification Requirement Percent of Goal Achieved = 101.40 % Porosity: 0.30
Depth below perforated pipe if present: 5.25 ft Depth: 0.00 ft Width: 0.00 ft Width: 0.00 ft
Length: 0.00 ft Length: 0.00 ft
Area: 300.00 ft2 Area: 0.00 ft2
Select paved area type
Buffer Strips & Bovine Terraces
C: 0.05 - 0.15 in/hr infiltration (transmission) rate
Urban districts - Commercial and business
BMP Volume
Below Ground
Ponded
Water Above
Ground
Steele Lane Apartments
TRIB-3
Delta Volume & Treatment
Priority 2: P2-04 Roadside Bioretention - Curb Opening Select disconnection condition
Release 8 Rev. 5
10/13/2022

STORM WATER CALCULATOR
BMP Tributary Parameters Project Name:

BMP ID:

BMP Design Criteria:

Type of BMP Design:

BMP's Physical Tributary Area: 9,059.0 ft2
Description/Notes:

Runoff Reduction Measures Resulting reduced Tributary Area used for BMP sizing = 6,846.3 ft2 Total Runoff Reduction Measures = 2,212.8 ft2
Interceptor Trees
Number of new interceptor Evergreen Trees : 0 Total Number of New trees in BMP Tributary Area: 8 Number of new interceptor Deciduous Trees : 8
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: 5,651 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 = 287.46 ft3 Post development hydrologic soil type within tributary area:

Post development ground cover description:

CNPOST : 94
User Composite post development CN: 0.0
BMP Sizing Tool: Hydromodification Requirement Percent of Goal Achieved = 100.88 % Porosity: 0.30
Depth below perforated pipe if present: 3.58 ft Depth: 0.00 ft Width: 0.00 ft Width: 0.00 ft
Length: 0.00 ft Length: 0.00 ft
Area: 270.00 ft2 Area: 0.00 ft2
Select paved area type
Buffer Strips & Bovine Terraces
C: 0.05 - 0.15 in/hr infiltration (transmission) rate
Urban districts - Commercial and business
BMP Volume
Below Ground
Ponded
Water Above
Ground
Steele Lane Apartments
TRIB-4
Delta Volume & Treatment
Priority 2: P2-05 Roadside Bioretention - No Curb AND Gutter Runoff is directed across landscape; Width of area: 5' to 9' Release 8 Rev. 5
10/13/2022

STORM WATER CALCULATOR
BMP Tributary Parameters Project Name:

BMP ID:

BMP Design Criteria:

Type of BMP Design:

BMP's Physical Tributary Area: 2,226.0 ft2
Description/Notes:

Runoff Reduction Measures Resulting reduced Tributary Area used for BMP sizing = 1,737.8 ft2 Total Runoff Reduction Measures = 488.3 ft2
Interceptor Trees
Number of new interceptor Evergreen Trees : 1 Total Number of New trees in BMP Tributary Area: 1 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: 1,153 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 = 72.98 ft3 Post development hydrologic soil type within tributary area:

Post development ground cover description:

CNPOST : 94
User Composite post development CN: 0.0
BMP Sizing Tool: Hydromodification Requirement Percent of Goal Achieved = 102.93 % Porosity: 0.30
Depth below perforated pipe if present: 1.17 ft Depth: 0.00 ft Width: 0.00 ft Width: 0.00 ft
Length: 0.00 ft Length: 0.00 ft
Area: 214.00 ft2 Area: 0.00 ft2
Select paved area type
Buffer Strips & Bovine Terraces
C: 0.05 - 0.15 in/hr infiltration (transmission) rate
Urban districts - Commercial and business
BMP Volume
Below Ground
Ponded
Water Above
Ground
Steele Lane Apartments
TRIB-5
Delta Volume & Treatment
Priority 2: P2-05 Roadside Bioretention - No Curb AND Gutter Runoff is directed across landscape; Width of area: 5' to 9' Release 8 Rev. 5
10/13/2022

STORM WATER CALCULATOR
BMP Tributary Parameters Project Name:

BMP ID:

BMP Design Criteria:

Type of BMP Design:

BMP's Physical Tributary Area: 6,439.0 ft2
Description/Notes:

Runoff Reduction Measures Resulting reduced Tributary Area used for BMP sizing = 4,801.0 ft2 Total Runoff Reduction Measures = 1,638.0 ft2
Interceptor Trees
Number of new interceptor Evergreen Trees : 0 Total Number of New trees in BMP Tributary Area: 4 Number of new interceptor Deciduous Trees : 4
Square footage of qualifying existing tree canopy: 1,006.0 ft2 Disconnected Roof Drains
Select disconnection condition:

Disconnected Roof Drains Method 1 Disconnected Roof Drains Method 2 Roof area of disconnected downspouts: 2,940 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 = 201.59 ft3 Post development hydrologic soil type within tributary area:

Post development ground cover description:

CNPOST : 94
User Composite post development CN: 0.0
BMP Sizing Tool: Hydromodification Requirement Percent of Goal Achieved = 101.08 % Porosity: 0.30
Depth below perforated pipe if present: 2.17 ft Depth: 0.00 ft Width: 0.00 ft Width: 0.00 ft
Length: 0.00 ft Length: 0.00 ft
Area: 313.00 ft2 Area: 0.00 ft2
Select paved area type
Buffer Strips & Bovine Terraces
C: 0.05 - 0.15 in/hr infiltration (transmission) rate
Urban districts - Commercial and business
BMP Volume
Below Ground
Ponded
Water Above
Ground
Steele Lane Apartments
TRIB-6
Delta Volume & Treatment
Priority 2: P2-05 Roadside Bioretention - No Curb AND Gutter Runoff is directed across landscape; Width of area: 5' to 9' Release 8 Rev. 5
10/13/2022
Soil Map—Sonoma County, California
(1650 West Steele Lane)
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
3/29/2019

Page 1 of 3 ends

Soil Map may not be valid at this scale.

Warning: Soil Map may not be valid at this scale.

Please rely on the bar scale on each map sheet for map
measurements.

Source of Map: Natural Resources Conservation Service
Web Soil Survey URL:

This product is generated from the USDA-NRCS certified data as of the version date(s) listed below.

Soil Survey Area: Sonoma County, California
Survey Area Data: Version 12, Sep 13, 2018
Soil map units are labeled (as space allows) for map scales 1:50,000 or larger.

Soil Map—Sonoma County, California
(1650 West Steele Lane)
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
3/29/2019

Page 2 of 3 ends

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BMP Selection Table APPENDIX B
A-7
Project Name: _______________________________________
Best Management
Practice (BMP)
Detail
Sheet Detail Title Can be used with…High Ground WaterContaminationSlope ConstraintsAchieves…TreatmentVolume CaptureRunoff Reduction MeasureBMP in priority selected?Yes No Unique Identifier of BMP per planesExplanation of selection Other notes:

Living Roof N/A N/A X X X X X
Rainwater
Harvesting N/A N/A X X X X
Interceptor Trees N/A N/A X X X X
Bovine Terrace RRM-01 Bovine Terrace X X
Vegetated Buffer
Strip RRM-02 Vegetated
Buffer Strip X
Impervious Area
Disconnection N/A N/A X X X X
Bioretention P1-02
Roadside
Bioretention -
no C & G
X X
Vegetated Swale-
with Bioretention P1-06 Swale with
Bioretention X X
Constructed
Wetlands N/A N/A X X
P2-02
Roadside
Bioretinton -
Flush Design
Roadside
X X
P2-03
Roadside
Bioretenion-
Contiguous SW
X X
P2-04
Roadside
Bioretenion-
Curb Opening
X X
P2-05
Roadside
Bioretenion- No
C & G
X X
Constructed
Wetlands N/A N/A X X
Date: _______________ Page _____ of _____
Bioretention
Universal BMP- to be
considered on all
projects.

Runoff Reduction
Measures
Priority 1- to be
installed with no
underdrains or liners.

Must drain all stading
water within 72
hours.

Priority 2 BMPs- with
subsurface drains
installed above the
capture volume.

Form A
Storm Water Quality Feature Maintenance Check List
- Standard Conditions -
Inspection Status Codes:

Are there any special conditions and/or maintenance requirements noted for BMP(s)? Y N (circle one) Reference code D1 D2 D3 D4 E1 E2 E3 E4 E5 E6 V1 V2 V3 V4 G1 G2 G4 S BMP ID:

Evidence of standing or ponding of
water in the BMP area after 72 hours
of dry weather?
Does the high flow bypass function as
designed?
Is there sediment acumination in or
around BMP?
Has water been observed flowing in
the pervious concrete section during
a low intensity storm?
Is there under cutting or washouts
along the sidewalks and/or curbs
abutting the planter area?
Is there channelization (gully)
forming along the length of the
planter area?
Is there accumulation of sediment
(sand, dirt, mud) in the planter area ?
Observed or potential transport of
mulch to drainage system?
Are there voids or holes present in
the BMP?
Is there evidence of animal activity?
Is the vegetation clogging the inlet or
flow path?
Evidence of Excessive Mowing and/or
Herbicide Overuse?
Are there dead or dry plants or
excessive weeds?
Is there an absence of correct
vegetation?
Is there debris/trash accumulation in
the BMP or high flow by pass?
Missing or damage structural
features?
(Grates, pipes, walls, curbs, etc.)
Evidence of improper modifications
or removal of BMP?
See Additional Special Conditions or
Features Check List Requirement
Form B
Office Use:

Complete: _______ Issues Corrective Action: _______ Re-Inspection Required: __________ Drawdown - Drainage - Vector Risk - Pump Out-
Blockage Hydraulic Function - Failure - Sediment Clogging Excessive Mowing - Herbicide Overuse -
Health of Desired Vegetation -
Date: _________________
Project: __________________________________________
S = Satisfactory
Inspector: _________________________________________
If Yes, attach Form B for Project.

Drainage Erosion Vegetation
Start Time: _______________
Address: __________________________________________Stop Time: _______________ D = Deficient
Page _____ of ______
General
Trash and Debris - Improper
Modifications - Damage
Special
Features
* = Refer to Form B (Specials)
and/or Form C (Notes).

Storm Water Quality Special Feature Maintenence Check List Page _____ of _____
Inspection Status Codes:

S = Satisfactory * - See Notes on Form C
D = Deficient
Reference code S1 S2 S3 S4 S5 S6 S7 S8 S9 S10
Additional
Special
Maintenance
Inspection
Criterial
BMP ID:

Office Use:

Complete: _______ Issues Corrective Action: _______ Re-Inspection Required: __________ Address: ________________________________
Date: _________________
Start Time: _________________
Stop Time: _________________
Inspector: _______________________________
Project: ________________________________
Add special inspection requirements in
addition to Form A here.

Add special inspection requirements in
addition to Form A here.

S11Add special inspection requirements in
addition to Form A here.

Special Feature or Conditions
Form C
Storm Water Quality Feature Maintenence Check List
- Inspection Notes -
Project: __________________________________________
Address: __________________________________________
BMP ID:

Date: _________________ Inspector: _________________________________________ Reference
Code Notes
Page _____ of _____
Declaration of Covenants Regarding Maintenance of Storm Water BMP Facilities- Version 1.2

Page 1 of 4 ends

RECORDING REQUESTED BY
AND WHEN RECORDED MAIL TO:

City of Santa Rosa- Utilities Department
Storm Water & Creeks Section- Supervising Engineer
69 Stony Circle
Santa Rosa CA 95401

Project/Property: Steele Lane Apartments
APN(s): 041-042-012

Santa Rosa, California

DECLARATION OF COVENANTS REGARDING MAINTENANCE OF

STORM WATER BMP FACILITIES

This Declaration of Covenants Regarding Maintenance of Storm Water BMP Facilities (“Declaration”) is made on this day of , 20 , by
Stagecoach Development Company, Inc. (“Landowner”) .

RECITALS

A. Landowner is the fee simple owner of certain real property located in the City of Santa Rosa (“City”), Sonoma County, California, 041‐042‐012 and more fully described in Exhibit A to this Declaration (“Property”).

B. The City’s National Pollutant Discharge El imination System (“NPDES”) Municipal Separate Storm Sewer System (“MS4”) Permit, Order number R1-2009-0050, issued by the North Coast Regional Water Quality Control Board, requires the City to implement and enforce specific requirements for the c onstruction and maintenance of onsite storm water management facilities/ best management practices (collectively, “BMP”) for development, redevelopment, and other applicable projects with the goal of mitigating impacts to storm water quality and runoff volume discharges into the MS4.

C. Provisions of Chapter 17-12 and other applicabl e sections of the Santa Rosa City Code shall apply to the construction, inspection and maintenance of BMP facilities and the enforcement of MS4 Permit requirements.

D. On , approved
Landowner’s IMPROVEMENT PLANS (“Plan”) and a Final
Standard Urban Stormwater Mitigation Plan (SUSMP”) for the Property which require the construction and maintenance of BMP facilities on the Property (the “BMP Facilities”) by Landowner. The BMP Facilities required under the SUSMP may include both built and Declaration of Covenants Regarding Maintenance of Storm Water BMP Facilities- Version 1.2

Page 2 of 4 ends

landscaping features. The
may be inspected at the City of Santa Rosa, Department of Utilities, Storm Water & Creeks Section, 69 Stony Circle upon appointment.

E. The SUSMP
make and execute this Declaration.

DECLARATION OF COVENANTS
requires that Landowner
NOW, THEREFORE, in consideration of the foregoing recitals, Landowner hereby covenants, agrees and declares as follows:

1. Landowner shall, at Landowner’s sole cost and expense, construct, inspect, and maintain the BMP Facilities in accordance with the Plan and the SUSMP.

Landowner shall assure that all BMPs rem ain fully functional and that all areas identified in the Plan and SUSMP for treatm ent and/or volume capture discharge to the specified BMP as designed.

2. Landowner shall keep all records related to ann ual inspections of BMP’s by City and all records related to BMP maintenance for a period of at least five years. The records shall include records of any BMP Facilities corrections, repairs, and replacements. Landowner shall make these records available to the City upon request.

3. In the event Landowner fails to maintain the BMP Facilities in good working condition as solely determined by the City, the City may enter upon the Property and take whatever steps it deems reasonably necessary to maintain and/or make in good working condition, such BMP Facilities. It is expressly understood that the City is under no obligation to maintain or repair the BMP Facilities, and in no event shall this Declaration be construed to impose such an obligation on the City.

4. In the event that the City performs work of any nature, or expends any funds in the performance of such work for labor, use of equipment, supplies, materials, or the like, due to failure of the Landowner to perform its maintenance obligations under this Declaration, as sole ly determined by City, Landown er shall reimburse the City within 60 days of receipt of notice for all costs incurred by the City to undertake such work. Costs shall include, but are not limit ed to, the actual cost of construction, maintenance and/or repair, and administrative costs directly related to such work.

5. Any violation of the Plan or SUSMP by Landowner shall be deemed a public nuisance under Chapter 1-30 of the Santa Rosa City Code and City shall be entitled to the remedies available to it under Chapter 1-30 in addition to those available to it under Chapter 17-12. The remedies identified herein shall be in addition to and cumulative of all other remedies, criminal or civil, which may be pursued by the City.

PLAN
Declaration of Covenants Regarding Maintenance of Storm Water BMP Facilities- Version 1.2

Page 3 of 4 ends

6. Landowner shall indemnify, defend and hold harmless the City and its employees, officials, and agents, from and against any liability, (including liability for claims, suits, actions, arbitration proceedings, administrative proceedings, regulatory proceedings, losses, expenses or costs of any kind, whether actual, alleged or threatened, interest, defense costs, and expert witness fees), where the same relates to, or arises out of, the construction, presence, existence, inspection, or maintenance of BMP Facilities on the Property or the perfo rmance of the covenants underlying this Declaration by Landowner, its officers, employees, agents, contractors or sub- contractors, excepting only that resulting from the sole, active negligence or intentional misconduct of the City, its employees, officials, or agents. This indemnification obligation is not limited in any way by any limitation on the amount or type of damages or compensation payable to or for the Landowner or its agents under workers’ compensation acts, disability benefits acts or other employees’ benefits acts. If any judgment or claim against the City, its officials, agents, or employees, shall be entered, Landowner shall pay all cost and expenses in connection therewith.

7. If any provisions of this Declaration shall be held to be invalid, illegal or unenforceable, the validity, legality and enfor ceability of the rema ining provisions shall not in any way be affected or impaired thereby.

8. This Declaration shall be governed according to the laws of the State of California.

The parties hereto agree that the forum for the adjudication of any dispute related to this Declaration shall be brought exclusively and solely in Sonoma County, California.

9. Landowner shall not assign this Declaration to a third party without the express prior written consent of the City, provided that such consent will not be unreasonably withheld and that such consent shall not be required for Landowner to sell or lease the property to a third party.

10. Landowner binds itself, its partners, successors, legal representatives and assigns to the City, and to the partners, successors, legal representatives and assigns of the City with respect to all promises and agreements contained herein.

11. This Declaration shall be recorded by Landowner, and shall: a) constitute a “covenant running with the land;” b) be binding upon Landowner and Landowner’s successors, heirs, and assigns in perpetuity; and, 3) benefit the City of Santa Rosa, its successors, and assigns. Any breach of this Declaration shall render Landowner Declaration of Covenants Regarding Maintenance of Storm Water BMP Facilities- Version 1.2

Page 4 of 4 ends

or Landowner’s heirs, successors or assigns liable pursuant to the provisions of the Santa Rosa City Code.

12. Any notice, submittal or communication required or permitted to be served on Landowner or City may be serv ed by personal delivery to the person or the office of the person identified below. Service may also be made by mail, by placing first-class postage, and addressed as indicated below, and depositing in the United States mail to:

City Representative: Landowner or Landowner Representative:

City of Santa Rosa Name:

Utilities Department Address: Stagecoach Development
Storm Water & Creeks Section Company, Inc.

Supervising Engineer 19 Leona Drive
69 Stony Circle San Rafael CA 94903
Santa Rosa CA 95401

Executed as of the day and year first above stated.

LANDOWNER:

Name:

Signatures of Authorized Persons:

By:

Print Name:

Title:

By:

Print Name:

Title:

ATTACHMENTS:

Exhibit A- Property Description
Notary Acknowledgment

Santa Rosa City CouncilMay 23, 2023

Santa Rosa City Council
May 23, 2023