Lake Logan Dam is a Class I high hazard dam located in Lake Logan State Park in Hocking County, Ohio. The dam was originally constructed in 1949 and was modified in 1954 after stability concerns were identified. The dam requires rehabilitation as the current spillway does not meet current dam safety requirements, the lake drain is deficient, and the toe drain requires replacement. Due to the deficiencies observed, Ohio Department of Natural Resources has identified Lake Logan as a high priority structure to be rehabilitated.

AK Hydro is serving as a subconsultant to DLZ, Ohio offering multiple services for the rehabilitation of Lake Logan Dam that includes preliminary design, alternatives design and evaluation, final design, and emergency action plan and operation and maintenance manual updates.

AK Hydro completed the hydrologic analysis of the watershed and routing analyses for the existing dam and rehabilitation alternatives. Coordination with ODNR Dam Safety was required to obtain approval of both the existing and proposed conditions. AK Hydro performed hydraulic calculations for sizing the rehabilitated spillway and stilling basin. Multiple iterations were completed to develop the most efficient design alternative.

AK Hydro worked closely with DLZ to evaluate cost-effective design alternatives for the Lake Logan Dam rehabilitation. The team conducted a site visit with the client to identify existing deficiencies and coordinated with ODNR Dam Safety through multiple review discussions. Based on evaluation of existing data, the team selected a major spillway rehabilitation approach to address deterioration, structural stability concerns, and inadequate protection against the hydraulic jump. Additional improvements for the deficient lake drain structure will include repairs to concrete and a replacement gate.

AK Hydro is also supporting the design of various site elements including a pedestrian bridge across the spillway chute, an access bridge to the lake drain, and surface  drainage improvements. The teams are working closely to develop the construction water control plan and cost estimates that meet the project goal. The project is currently in final design and will be bid using the general contracting delivery method. Upon completion, AK Hydro will lead updates to the Emergency Action Plan (EAP) and Operations, Maintenance, and Inspection (OMI) manual, and will provide construction drawings, specifications, peer review of DLZ design work, and construction-phase support.