Portage Lakes Spillway Adequacy Study and Dam Rehabilitation

The Portage Lakes is a system of several natural and man-made lakes and canals constructed in the 1840s as a system of interconnected feeder lakes to provide water for the Ohio and Erie Canal.  The lakes are currently used for recreation and to augment the industrial water supply for the City of Akron. DLZ was retained to evaluate the outflow and flood storage capacities of the Portage Lakes with respect to current state safety standards and to evaluate daily lake levels and flood control capabilities of the existing gate structures and spillways.

Included in this study were the East, West, and North Reservoirs, the Tuscarawas River Diversion Dam, and Long Lake. Detailed analyses of watershed hydrology and system hydraulics were performed.  Hydrologic computations to determine inflows for several flood frequencies, including the Probable Maximum Flood (PMF), were carried out using HMR 52 and HEC-1.  Dam failure analyses using the DAMBRK computer program were performed.  Results of the dam failure analyses were used to prepare Emergency Action Plans.