Adams Lake Dam is a Class I high hazard dam located in Adams Lake State Park in Adams County, Ohio. The dam was originally constructed in 1947 and was modified in 1993 after a seepage failure within the dam embankment. The dam requires rehabilitation as the current dam configuration can only pass 61% of the probable maximum flood without overtopping the dam embankment. In addition to capacity issues, recent evaluations have determined that the principal spillway fails to meet current dam safety standards and requires a complete replacement.

The Ohio Department of Natural Resources identified Adams Lake as a high priority structure to be rehabilitated.  The proposed design will include a spillway, embankment, and lake drain improvements and will address all critical deficiencies to ensure full compliance with dam safety regulations. The design team considered the following rehabilitation design alternatives during Preliminary Design:

• Replacement spillway with increased discharge capacity
• Replacement spillway and emergency spillway widening
• Replacement spillway with embankment modifications to increase storage capacity.
• RCC embankment overtopping protection system with in-kind spillway replacement