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<br />City of Redwood City 1017 Middlefield Road, Redwood City, CA. 94063 Tel: 650-780-7000 www.redwoodcity.org
<br />Because preparing a master plan is a costly, multi-year effort, and current resources are limited, the City
<br />advanced the Roadmap as a practical first step. This approach allows the City to clarify what technical
<br />studies, data collection, and analyses would be necessary for a master plan and to assess whether a
<br />phased or comprehensive effort is the more viable option.
<br />The Roadmap recommends that the elements and sub-assessments outlined below be completed as part
<br />of a future master plan. A cost estimate range for the completion of each component is included.
<br />Data gaps analysis: A data gaps analysis is recommended to review existing information and
<br />identify missing data needed for future condition and capacity assessments. The effort would also
<br />highlight areas requiring field verification. The Roadmap includes an analysis that may be used as
<br />a starting point for this effort. The estimated cost is $10,000–$20,000.
<br />Topographic Surface Information Collection: A comprehensive citywide topographic surface is
<br />recommended, including open channels, creek geometries, and overbank areas, supplemented
<br />by bathymetric surveys of lagoons, basins, and creeks. The estimated cost is $300,000–$600,000.
<br />Infrastructure data collection and condition assessment: A thorough assessment is
<br />recommended to support prioritization of stormwater system improvements. Field surveys would
<br />document the condition of pipes, channels, culverts, bridges, basins, lagoons, pump stations, and
<br />green infrastructure. The assessments would evaluate structural condition, hydraulic capacity,
<br />and maintenance needs. Estimated costs range from $540,000 to $980,000 across all facility
<br />types.
<br />Hydrologic and hydraulic model: The City’s stormwater conveyance system should be modeled
<br />to evaluate capacity and system performance. The analysis would use industry-standard tools,
<br />incorporate updated rainfall and tidal data, and simulate 10-year and 100-year storm events in
<br />accordance with City and County design criteria. The model would assess pipes, channels, and
<br />green infrastructure and identify bottlenecks and undersized facilities. The estimated cost is
<br />$200,000–$400,000.
<br />Climate change projections: Hydrologic and hydraulic modeling should incorporate climate-
<br />adapted design criteria, including projected rainfall, sea-level rise, and emergent groundwater
<br />conditions, as well as compound flooding scenarios that combine coastal surge and rainfall in
<br />tidally influenced areas. The estimated cost is $40,000–$60,000.
<br />Shoreline infrastructure: Recommended shoreline infrastructure improvement projects from the
<br />Sea-Level Rise Vulnerability and Adaptation Planning Study (ESA, 2024), should be catalogued and
<br />evaluated in the overall prioritization of capital improvement projects. The estimated cost is
<br />$20,000–$40,000.
<br />Identifying and prioritizing capital improvement projects: Capital improvement projects should
<br />address both conveyance and shoreline infrastructure, using hydraulic modeling and condition
<br />assessments to identify level of service limitations. Initial project priorities should consider life
<br />safety and property damage potential and be reviewed by the City. Once critical projects are
<br />identified, priority rankings, cost estimates, and a phased Capital Improvement Program (CIP)
<br />should be developed. The estimated cost is $60,000–$80,000.
<br />Cost estimates: Cost estimates for identified projects should be developed using regional data,
<br />published sources, and recent bid information. Estimates should reflect condition-based
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