Hills Pond Dam Remediation
Portage County, OH
EMH&T is working with Portage County, Ohio officials to bring the Hills Pond Dam along the Little Cuyahoga River into compliance with State of Ohio dam safety requirements. The Ohio Department of Natural Resources (ODNR) had previously issued a Dam Safety Inspection Report identifying multiple deficiencies with the existing dam. EMH&T provided a variety of professional services on this project, including relevant data collection about the dam from both local and federal sources, as well as data collection on the nearby Mogadore Reservoir and Wingfoot Lake dams. We also completed field surveying and the corresponding base mapping, and collection of data on three downstream bridges owned by the Wheeling and Lake Erie Railway. EMH&T engineers completed a watershed-scale hydrologic and hydraulic (H&H) analyses to estimate the flood inflow hydrographs and peak streamflow conditions for the Little Cuyahoga River at the location of the dam. This information was used to simulate a dam-break scenario and to determine the impact of flooding downstream from the dam. EMH&T also used the results of the H&H analyses to estimate the capacity of the existing Hills Pond Dam spillway system. Based on the technical information, we evaluated options which would modify the existing dam to bring it in compliance with dam safety regulations, or eliminate the dam and restore a geomorphically stable and functional river channel through that reach of the river. EMH&T’s investigation included the regulatory consequences of the various options and both the short- and long-term costs associated with each option. We provided recommendations aimed at addressing the county’s goal of reducing the potential for future liabilities related to the existing dam.