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TA. - Page 86
<br />drainage concepts for identified Drainage Areas 91 and #2: (1) an on-site, underground detention vault with media
<br />filter near Bradford, which would retain and treat 72 percent of the site drainage area (16,134 square feet) before
<br />the storm water enters the City system; and (2) raised planters that would serve as a bioretention area on the
<br />second floor outdoor terraces, and would retain and naturally filter the other 28 percent of the site drainage area
<br />(6,400 square feet) before the storm water enters the City system. All design of biotreatment measures is consistent
<br />with technical guidance for the applicable type of biotreatment measure provided in Chapter 6 of the C.3 Technical
<br />Guidance. Plan Sheets C8.00 and C9.00, 3125116, and Plan Sheets LI.0 and LL2, 3114116, illustrate and summarize
<br />the drainage plans and calculations per City criteria, and identify the proposed locations and details of the media
<br />filter vault and bioretention areas. The project -specific preliminary engineering study provides further details (BKF
<br />Engineers, October 26, 2015).
<br />All storm water data and components provided by the project applicant are subject to review, approval, and on-site
<br />inspection by the City. The project would be subject to the above standard requirements as conditions of project
<br />approval. As a result of DTPP standards and the City requirements described above, the proposed project would
<br />not generate additional storm water drainage impacts beyond those analyzed in the DTPP program EIR.
<br />d. The DTPP program EIR (pp. 10-8 and 10-9) concluded that development facilitated by the DTPP would have no
<br />impact on water supply. The City has a contract with the San Francisco Public Utilities Commission (SFPUC) for
<br />the provision of an annual supply of 12,243 acre-feet of water through the year 2034. The City's 2010 Urban Water
<br />Management Plan (UWMP) accounts for development that would occur pursuant to the City's adopted General
<br />Plan through 2030, including all projected growth under the Mixed Use — Downtown land use designation, which is
<br />implemented through the DTPP. The annual water supply from SFPUC is sufficient to supply and service the
<br />proposed project. Furthermore, Redwood City has not experienced any cutbacks or reduction in its water supply
<br />guarantee from SFPUC, and the City is not in a period of water rationing; therefore, no additional water supply
<br />evaluation would be required (Redwood City Public Works memorandum, 6126115). Also, the DTPP program EIR
<br />(pp. 10-9 and 10-10) concluded that impacts resulting from DTPP facilitated development on the water distribution
<br />system and on fire flow would be less than significant (see item XIV of this checklist regarding fire flow
<br />requirements).
<br />Based on City engineering factors used to calculate projected water demand (included as Attachment Q in the
<br />Preliminary Engineering Study, 603 Jefferson Avenue, Redwood City, California 94603, prepared by BKF
<br />Engineers; October 26, 2015), the water demand for the 603 Jefferson Avenue project is forecast at 13,473 gallons
<br />per day (gpd), which includes the residential/commercial uses and landscaping. The BKF Attachment Q based its
<br />calculation on 91 residential units and 11,000 square feet (sq. ft.) of commercial rather than the project's 4,500 SF
<br />of commercial, which would result in the need for 12,585 gpd. 3 Therefore, the BKF calculation is a conservative
<br />estimate, and the project would require less water.
<br />The City Recycled Water Ordinance (Chapter 38, Article VIII of the Municipal Code) requires the use of recycled
<br />water, where available, for landscape irrigation and appropriate building plumbing (e.g., water closets, urinals). At
<br />this time, recycled water service has not been extended to the project site; however; the project has been designed
<br />and would be constructed with dual plumbing, which initially would carry domestic water, then recycled water when
<br />that system is eventually extended to the site (BKF Engineers p. 2 and Plan Sheet C8.00, 3125116). Landscape
<br />irrigation would conform to all City regulations and the California Water -Efficient Landscape Ordinance, which
<br />means in part that all plantings would be irrigated with an automatic drip, micro -spray, or bubbler system using a
<br />rain sensor. All project utility calculations and designs are subject to review and approval by the City.
<br />As a result of DTPP standards and the City requirements described above, the proposedproject would not generate
<br />additional water supply impacts beyond those analyzed in the DTPP program EIR.
<br />e. The DTPP program EIR (pp. 10-15 and 10-16) concluded that the South Bayside System Authority (SBSA)
<br />wastewater treatment plant would not be significantly impacted by development allowed under the DTPP, which
<br />includes the proposed project. Based on City engineering factors used to calculate projected wastewater generation
<br />(95 percent of water demand — see [d] above, and Attachment L in the Preliminary Engineering Study), the
<br />wastewater generation for the 603 Jefferson Avenue project is forecast at 12,763 gpd. 5 All project -related
<br />3 Based on City engineering factors, 91 units x 2.2 persons/ unit = 200 persons x 60 gpd per person = 12,000 gpd for
<br />residential. 4,500 sq. ft. commercial x 0.13 gpd/sq. ft. = 585 gpd for commercial. Total water demand = 12,000 gpd + 585
<br />gpd = 12,585 gpd.
<br />s Again, the BKF sewer calculations were based on 91 residential units and 11,000 sq. ft. commercial instead of the project's
<br />91 residential units and 4,500 sq. ft. commercial, which would result in: 12,000 gpdw (Attachment Q water) x 0.95 = 11,400
<br />gpd (sewer) for residential, and 585 gpdw (Attachment Q water) x 0.95 = 555.75 gpds (sewer) for commercial. Total sewer
<br />demand = 11,400 gpds (res'l) + 555.75 gpds (comm'1) + 3.52 gpds (PVC pipe infiltration factor) = 11,959.27 gpd. As with
<br />water demand, the BKF calculation is a conservative estimate, and the project would generate less wastewater.
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