Windmiller Dam Evaluation
In response to an Ohio Department of Natural Resources (ODNR) Dam Inspection Report to the City of Pickerington, Ohio, the city selected EMH&T to conduct a professional dam safety evaluation of the Windmiller Dam, which is a 1,000 foot long earthen embankment constructed in 1962. The ODNR report noted several deficiencies, including insufficient spillway capacity, lack of a lake drain, and lack of an Emergency Action Plan (EAP) and Operation, Maintenance and Inspection (OM&I) plan. EMH&T’s evaluation is designed to provide insight on how the city could either bring the dam into compliance with ODNR guidelines or how to modify the existing structure such that it is no longer qualifies for regulation as a dam by the ODNR. EMH&T provided the City with a preliminary engineering report including hydrologic and hydraulic studies, as well as a field surveying of surrounding property boundaries, the dam crest, and downstream channel cross sections to better understand conditions affecting the dam’s spillway operation. EMH&T also conducted a jurisdictional delineation of waters of the U.S within the project area. The preliminary engineering investigation considered: 1) improvements to the existing dam to address ODNR Dam Safety Program requirements; or 2) converting the facility to a dry stormwater management facility with a restored stream channel to provide ecosystem enhancements while also controlling stormwater runoff from the surrounding developed areas.