NEORSD Woodland Central Green Infrastructure

Coldwater provided planning, design, hydraulic modeling and permitting services for NEORSD’s Woodland Central Green Infrastructure project. The overall project goal was to reduce combined sewer overflow volume and frequency through the installation of separate storm sewers in an urbanized area of the City of Cleveland. The project included 4,900 linear feet of new mainline separate storm sewer, two extended detention basins, and two structural storm water BMP’s (Stormceptor hydrodynamic separator and Suntree nutrient separating baffle box).

Design of the water quality basins required meeting both the State water quality treatment standards, and Ohio EPA Rule 13 permit requirements, as the basin sites were located on environmentally contaminated sites that required remediation as part of the site design. Coldwater assisted in the development of basin alternatives that were considered and analyzed to minimize the amount of solid and contaminated waste that required handling, saving hundreds of thousands of dollars in construction cost.

Coldwater completed hydraulic modeling services using PCSWMM software with a focus on the performance of the storm water conveyance system and detention basins. Hydraulic modeling, basin and site design were complicated by the need to coordinate with the concurrent design (by others) of the outfall sewer for both the east and west basins. This resulted in both design constraints of spatial footprint available, as well as hydraulic constraints in allowable discharge rates to the culvert.

Coldwater’s planning and design work was focused on the basin grading plans, outlet structures and structural storm water BMPs. Coldwater provided input into the specification of pipe materials and also supported Jacobs in the development of technical specifications included in construction bidding documents. Coldwater’s permit-related work for the project included the preparation of erosion and sediment control plan sheets and a storm water pollution prevention plan based on an NEORSD template document. Coldwater provided construction oversight assistance for the project, which was completed in 2019.