Reso25 16341 - Laserfiche WebLink

Browse Search

Introduction City of Redwood City (0011239.02)1-7 Woodard & Curran, Inc. Sanitary Sewer Capacity Master Plan November 2023 1.3.2 Seaport/Pacific Shores Network The Seaport/Pacific Shores sewer network, shown in Figure 1-3, serves the Port of Redwood City and adjacent areas east of Highway 101 along Seaport Boulevard. The Seaport/Pacific Shores modeled network includes 2.9 miles of gravity sewers ranging from 6 to 12 inches in diameter; 4.2 miles of 6- to 14-inch diameter force mains; and five City- owned pump stations. In addition, the system includes additional sewer mains and lift stations owned by the Port of Redwood City, which were not evaluated in this study. Wastewater from Seaport/Pacific Shores is conveyed either to Maple Street Pump Station or directly to the SVCW conveyance system, which ultimately conveys flow to the SVCW WWTP located in Redwood Shores. 1.3.3 Redwood Shores Network The Redwood Shores sewer network, also shown in Figure 1-3, serves the Redwood Shores part of Redwood City. The Redwood Shores system includes 31 miles of gravity sewers ranging from 4 to 15 inches in diameter; about 7 miles of 4- to 18-inch diameter force mains; and 26 City-owned pump stations. The system includes a few areas of private sewers and pump stations, which are not addressed in this study. The Redwood Shores system is hydraulically separate from the Main City and Seaport/Pacific Shores systems and conveys flow directly to the SVCW WWTP. 1.4 SCOPE OF STUDY The scope of the Master Plan, as well as a brief discussion of work conducted under each task, is described below. •Task 1 – Project Management and Coordination. Periodic progress meetings and teleconferences were held with City staff to review project status and discuss project issues, and monthly status reports were prepared to document the work completed. •Task 2 – Review Existing Information. This task involved assembling, organizing, and reviewing maps, documents, and data related to the collection system, including GIS files, maps and drawings of collection system facilities and recent sewer improvement projects; pump curves and operating data; pump station and treatment plant SCADA data; water use and customer account data; previous flow monitoring data and reports; the City’s General Plan and other relevant planning information; and sewer design standards and specifications. •Task 3 – Flow Monitoring. A plan for flow and rainfall monitoring in the collection system during the 2018/19 wet weather season was developed. The program included 40 flow meters and four rain gauges installed for a period of approximately two months. The monitoring was conducted by ADS Environmental Services (ADS) contracted directly to the City. •Task 4 – Develop Land Use Planning Information and Parcel Loads. Existing base wastewater flow (BWF) loads were developed for each parcel within the sewer service area based on customer sewer account and water consumption records. Future development information was compiled by planning staff in the City’s Community Development Department •Task 5 – Develop Design Flow and Hydraulic Criteria. The purpose of this task was to develop proposed design flow and hydraulic criteria to be used for evaluating the capacity of the Redwood City’s existing sanitary sewer system (including selection of appropriate design storm), identifying capacity deficiencies in the existing system, and planning design of new or relief sewers. The task also included review of the City’s Sanitary Sewer System Design Criteria. A technical memorandum (TM) was prepared to summarize the results of this task. •Task 6 – Develop Hydraulic Model. A hydraulic model of the City’s sewer system was developed using InfoWorks™ ICM software. Each parcel in the City’s sewer service area was associated to a sewer pipe in the sewer system model. Existing and future flow loads to the model were defined based on the data ATTY/RESO.0077/CC RESO SEWER SYSTEM MANAGEMENT PLAN - EXHIBIT A REV: 07-14-25 LF Page 113 of 317