Kleinfelder developed a new citywide 1D and 2D flood model of the City of Medford (City) stormwater system to help the City understand its inland flooding risks under present and future storm scenarios. Results from similar exercises conducted in the nearby cities of Cambridge and Somerville (also performed by Kleinfelder), demonstrated observed and projected increases in the frequency and intensity of precipitation-based flooding. Addressing vulnerabilities and reducing impacts and disruptions from such flooding is a near-term priority for the City.

Integrating Climate Change Scenarios in Drainage Model

The scenarios Kleinfelder used for the City include various rainfall design storms coupled with boundary conditions of current and future sea level rise and storm surge. The 1D model identifies capacity issues in the City’s drainage system, and the 2D model shows the areas where conveyance and inlet capacity issues are likely to manifest as flash flooding and sewer overflows. The model results have been used for the City’s Climate Change Vulnerability Assessment, Climate Action, and Adaptation Plan, as well as broader resiliency planning efforts.

Regional Watershed Flood Model

In addition to the citywide model, Kleinfelder, working with Stantec and Weston & Sampson, developed a regional hydrologic model for the entire Upper Mystic River Watershed. This model includes future sea level rise and storm surge conditions, pumping operations at the Amelia Earhart Dam, as well as increased river flows from surrounding communities due to extreme precipitation. Modeling results are used to help coordinate watershed projects and investments in equitable outcomes, prioritizing vulnerable populations and environmental justice communities.

Localized Stormwater Flood Mitigation Studies

Kleinfelder is working with the City on localized flood studies and mitigation projects in multiple neighborhoods, including conceptual design of a series of stormwater management improvements to Tufts Park. Planned improvements include a new 2-million-gallon subsurface detention tank and numerous green infrastructure improvements to the park which will alleviate current and future flooding within the park, surrounding neighborhood, and at an upgradient railroad underpass.

Project Results

The drainage flood model helped develop a set of flood maps under current and future climate conditions, and the results helped the City identify potential high flood-risk areas. The regional model serves as a valuable tool for the City’s flood preparedness.

Location:

Medford, Massachusetts

Owner:

City of Medford, MA