M E M O R A N D U M. Date: January 31, Bjorn Schrader, Abramson Teiger Architects. Kimley-Horn and Associates, Inc.

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1 M E M O R A N D U M Date: January 31, 2017 To: From: Subject: Bjorn Schrader, Abramson Teiger Architects Kimley-Horn and Associates, Inc Washington - Utility Memorandum Introduction Kimley-Horn and Associates, Inc. is providing this Utility Investigation Technical Memorandum based on our review of the project s Comprehensive Plan Package, provided by the Client, and our understanding of the existing utilities surrounding the site. A summary of our utility analysis for the proposed development is provided below. I. Sanitary Sewer: a. Existing Improvements: Existing sewer lines within Culver City are maintained by the City s Public Works Department. The existing sewer system for each street frontage are described further below: Washington Blvd: There is an existing 10 VCP sewer line south of the Washington Boulevard centerline which runs parallel to the westbound Washington Boulevard curb and gutter. In addition, there is also an existing 12 sewer line north of the Washington Boulevard centerline which runs parallel to the 10 sewer line. Based on City record plans from 1996 (Plan No ), the existing sewer systems were proposed to be lined. See below for images showing both sewer lines from the City s GIS site.

2 Pg. 2 b. Proposed Improvements: The following is based on the Area Calculations, prepared by others, included in the Comprehensive Plan package received from the Client: Proposed Project Development Programming: The project will develop or include the following: Restaurant 3,184 sf Office 59,325 sf Retail 2,878 sf Proposed Sewer Demand: Based on the above summary, the proposed project will generate cfs (38,342 gpd) of additional sewer discharge to the existing 10 sewer line within Washington Boulevard. This does not include potential credit for the existing use and sewer demand for the site, which would help to further reduce the proposed sewer demand. Our detailed analysis, based on the County of Los Angeles Sanitation District s sewer loading per unit or usage, is summarized in tabulation below.

3 Pg. 3 Sewer Capacity Analysis: Based on the City s previous analysis for the adjacent Washington/Landmark project, we have determined that the existing 10 sewer line would have adequate capacity for the 8888 Washington project. According to the sewer study prepared by the City in November 2010(see Attachment A) for the Washington/National Catalytic Projects, the maximum flow at the manhole on Higuera was 4.66 gpm or 6,710 gpd. See below for the metering location and summary of results. Metering Location: Flow Metering Location Map from Page 12 of Washington/National Sewer Study:

4 Pg. 4 Metering Data from the City Report dated November 2010 is summarized below.

5 Pg. 5 The 2010 sewer study also indicated that the expected sewer generation for the Washington/Landmark site is 32,728 gpd. The maximum allowed d/d is 0.5 and the calculated d/d after development is expected to be Therefore, our analysis builds on the following to confirm that the existing system has adequate capacity to serve the proposed development. See below for a sanitary sewer hydraulic analysis. Existing flow per sewer study 6,710 gpd Washington/Landmark Site (Platform Development) 32,728 gpd 8888 Washington Blvd 38,342 gpd Total 77,780 gpd

6 Pg. 6 Our analysis concludes that the existing 10 sewer line has adequate capacity based on the following summary: Existing d/d = 0.04 W/ Platform d/d = 0.14 W/ 8888 Washington d/d = < 0.50; Therefore OK

7 Pg. 7 II. Domestic/Fire Water a. Existing Improvements: Existing water lines within the City of Culver City are operated by the water purveyor Golden State Water Company (GSW). The information summarized below are based on the GSW Water Map, Topographic Survey, and Conceptual Street Utility Plan provided by the Client. 1) Water Line: Washington Blvd: There is an existing single 16 water line within Washington Boulevard which is located south of the roadway centerline per the GSW Water Map and Conceptual Street Utility Plan provided by the Client. GSW Record Water Map 2) Fire Hydrants: Based on the topographical survey, there is one existing fire hydrant located just east of the existing site frontage along Washington Boulevard based on the topographical survey provided. 3) Water Meters: Based on the topographical survey, there is one existing water meter shown midpoint along the Washington Boulevard frontage based on the topographic survey. Sizing of this meter is not shown on the survey, but the project should consider reusing the existing meter and lateral to the extent feasible.

8 Pg. 8 Project Survey with Existing Features Proposed Improvements: The following is based on the Conceptual Street Utility Plan, prepared by others, included in the Comprehensive Plan package received from the Client: Proposed Water and Fire Service Connection: The Conceptual Street Utility Plan shows the proposed 4 water/6 fire service connections for the project at the western end of the site on Washington Boulevard. The proposed connections will need to cross the existing 10 sanitary sewer line in order to tie into the existing water main located south of the Washington Boulevard centerline. If the existing water meter and lateral is chosen to be utilized, the existing meter would need to be relocated due to road widening.

9 Pg. 9 Kimley-Horn has obtained a preliminary fire flow availability from the City of Culver City in coordination with GSW. The initial fire flow of 65 psi (static) provided by the Culver City Fire Department was based on the flow rate from the existing hydrant (#406) 300 feet east of Robertson Boulevard. The test was completed September 26, Proposed Water and Fire Service Pressure Requirement: The project s plumbing engineer and/or fire service consultant will need to assess the project water/fire service design requirements based on the preliminary pressure information to be provided by GSW. The plumbing engineer will also need to assess the need for any booster pump for the project, in coordination with GSW and Culver City Fire Department. Water Conservation Features: The project will need to comply with the City s Low Impact Development (LID) guidelines and City s Streetscape Master Plan. Both of these require implementation of a stormwater treatment system for the site that captures the required volume of runoff for treatment. The LID system for the project will need to consider implementation of infiltration, rainwater capture and reuse, or a combination of treatment systems approved by the City. If the project site is not feasible for infiltration due to soil conditions or other limiting factors, the project would look at capture and reuse, such as a cistern/underground detention tank, that would reuse rainwater for irrigation purposes to conserve potable water. If the site contains minimal landscaping, and the City determines that capture and reuse is not feasible for the site, then biofiltration and/or flow treatment will be accepted. It is our understanding that the project will incorporate an extensive green roof per the provided Roof Planting Plan which will increase the pervious area within the project site and lower the area required to be treated. Per the provided LID Utility Plan, a Contech Peak Diversion StormFilter will be used to treat the required site runoff prior to entering a proposed catch basin along Washington Boulevard, and the public storm drain system immediately thereafter. See below for the provided LID Utility Plan.

10 Pg x 6 Peak Diversion StormFilter Standard Detail Other water conservation features include plumbing fixtures that meet or exceed water use limits per the CalGreen Standards along with drip irrigation system for the proposed landscape areas to be designed by the application project team members.