OAK CREEK, WI - EXPANSION
OWNER: We Power, LLC
LOCATION: Oak Creek, WI
VALUE: $105,358,725.00
The Oak Creek Expansion Project is a major portion of We Energies' Power the Future plan which includes the construction of the $2.2 billion Elm Road Generating Station. Bechtel Corporation is the General Contractor for the Elm Road units.
Under a Design/Build Subcontract from Bechtel, the joint venture of Kenny/Shea is constructing a water intake system to provide up to 2.2 billion gallons of cooling water per day to both the existing Oak Creek Power Plant as well as the expansion facility. Kenny/Shea has full design responsibility for the Intake Tunnel System including geotechnical and hydraulic design. Hatch Mott MacDonald is providing the engineering design and professional services to the Joint Venture.
For the main conveyance tunnel, Kenny/Shea excavated a lake water intake tunnel with its 27’ 4” diameter Robbins TBM in limestone approximately 9,200 feet in length. On-shore starter and tail tunnels were drilled and blasted at 30 feet diameter for 381 linear feet. The tunnel required advanced probe hole drilling and grouting. The project required lining intermittent portions of the tunnel to a finished diameter of 25 feet.
The system provides water to the existing Oak Creek Power Plant as well as the expansion facility. In order to accomplish this, Kenny/Shea constructed under an $8 million change order added to the contract, a roughly 150 feet by 150 feet Slurry wall basin onshore for the expansion facility and then connected this storage basin to the intake tunnel by an 18 feet finished diameter shaft from the bottom of the basin to the tunnel, 140 feet below.
Four 12 foot diameter steel lined intake shafts have been drilled one mile offshore in 43 feet of water, to just above the tunnel horizon, 150 feet below. Each vertical riser is connected to its own 9 foot diameter horizontal steel intake piping and manifold system including 24 specially constructed 8 foot diameter cylindrical wedge-wire screens to minimize impact to the aquatic life.
Kenny/Shea crews drilled and blasted from the crown of the tunnel up to the steel shaft liners above and made the permanent connections to the 27 foot tunnel. After filling the tunnel, divers will remove the offshore shaft caps completing the operating intake system. A 250 foot dike wall, with emergency bypass serves as a backup intake system, is included with a required 100,000 cubic yards of intake channel dredging.