Storm Drainage Master Plan, GPS Surveys and GIS Mapping
Vallejo Sanitation & Flood Control District, California
West Yost developed a Storm Drain Master Plan for VSFCD with a focus on the evaluation, alternatives, and cost estimates for addressing existing flooding problems. To assist in the master planning process, West Yost developed computer models of five watersheds within the District using the MOUSE hydrologic/hydraulic model package, and conducted GPS and Total Station field surveys of over 6,000 storm drain facilities. West Yost also evaluated the feasibility of redirecting the highly polluted first flush flows and dry weather flows from the District’s storm drain system into the District’s sanitary sewer system for treatment at the wastewater treatment plant, and assisted the District in public outreach for the master plan.
Because the City of Vallejo is nearly built out, this master plan focused on solving existing flooding problems rather than planning for future growth. The master plan is essentially a series of predesign reports for each of the 30 current flooding problems within the District. The major elements of this Flood Control Master Plan are described below:
- West Yost conducted a GPS and Total Station field survey of over 6,000 storm drain facilities, such as catch basins, maintenance holes, culverts, pump stations, and open-channel cross sections. The field survey was performed using a global positioning satellite system and included surveying the location and elevation of the facilities, measuring the depth to the pipe inverts, and measuring the pipe sizes. The field data were processed into an AutoCAD Map GIS database and a Storm Drain Facilities Map Book.
- West Yost developed computer models of five watersheds within the District using the MOUSE hydrologic/hydraulic model package. The models included all 36-inch and larger diameter pipes, pipes relevant to all flooding problems, and all major open channels. The models were calibrated to gauged flow records and previously observed flooding, and then they were used to develop solutions for the flooding problems.
- Predesign evaluations of the existing flooding problems were developed. These evaluations included developing, evaluating, and comparing alternative solutions to the flooding problems; estimating the construction and capital costs of the alternatives; and recommending a preferred alternative.
- West Yost evaluated the feasibility of redirecting the highly polluted first flush flows and dry weather flows from the District’s storm drain system into the District’s sanitary sewer system for treatment at the wastewater treatment plant. West Yost also developed a Capital Improvement Project and financing plan. All of the work described above was combined into a comprehensive 4-volume storm drain master plan.
The community was actively involved in the project through regular meetings with the District’s Citizen Advisory Committee and meetings with residents affected by the flooding problems.