In response to a USEPA consent decree, the Northeast Ohio Regional Sewer District (NEORSD) retained our project team to perform a sustainable watershed evaluation on the Doan Brook watershed. The Doan Brook watershed covers approximately 12 square miles and discharges more than 390 million gallons of combined sewer overflow annually to surface waters. Utilizing the sustainable watershed evaluation process (SWEP) developed by the project team, opportunities to remove stormwater runoff and natural stream base flows from the combined system are being identified. The outcome of the Doan Brook SWEP evaluation is a multi-objective solution with the goals of removing stormwater from the combined system, capturing and treating stormwater runoff in green infrastructure features throughout the watershed, and improving the flooding issues within Doan Brook. This process is a holistic approach that considers all possible solutions for integrating CSO controls into a larger vision for the entire community.

As the preliminary opportunities are refined and the green master plan is completed, green solutions will be incorporated in the combined system collection model to determine the CSO reduction benefits. Removing significant amounts of stormwater from the combined system and improving the capacity in Doan Brook will allow NEORSD to reduce the size and cost of the proposed Doan Valley Tunnel planned for CSO control. A preliminary cost benefit analysis of the green solution will determine the additional benefits and potential cost savings. Using the SWEP in the Doan Brook Watershed results in a sustainable solution that will not only achieve NEORSD’s stormwater reduction goals, but also provide other community benefits, such as increased green space, economic development, and community enhancement.