The Beaver Excavating Company was the Construction Manager at Risk (CMR) for North Reservoir Dam Rehabilitation Project at Portage Lakes, Summit County, Ohio. The North Reservoir Dam is a Class I high-hazard-potential structure, comprised of earthen embankments, and is located near the city of Barberton. Beaver’s CMR preconstruction services included estimates of probable construction cost, value engineering, construction schedules and constructability reviews. During construction, Beaver was responsible for the means and methods of construction, project safety, and project completion.
This Dam features a 90,000 sf Soil Cement (SC) Cut-off wall and Gravity Section (12,000 CY and 16,500 CY respectively). These SC Elements have an unconfined compressive strength of 200 psi and permeability equal to or less than 1.0 x 10-6 cm/sec. Beaver Excavating was chosen to self-perform all the project civil works but subcontracted the deep soil mixing component. Major civil work scope items included de-grading the existing dam to a work platform elevation, underwater berm placement, shore protection, and reinforced cap and parapet protection. This project also included bypassing the existing outfall spillway and complete reconstruction of the Spillway Structure. Together, the Beaver CMR team and Beaver’s self-performing crews and subcontractors worked collaboratively with the Ohio Department of Natural Resources (ODNR), and their Engineer of Record, to be very transparent with foreseen & unforeseen risks associated with the deep soil mixing operations within the 110-year-old earthen dam. These risks included organic soil mixing, difficult mixing of over 13,000 CY of silts and clays and encountered woody obstructions. Beaver was able to perform the project within ODNR’s budget with substantial savings realized through several Value Engineering measures including the earthwork abutment regrading and collaborative risk management approaches on various project elements.