On December 18, 2009, Cascade became the owner of Lake Tapps and Puget Sound Energy’s former White River project.

Cascade is preparing its 2010 Transmission and Supply Plan of which Lake Tapps will be a major component in Cascade’s long term water supply system over the next three or four decades.

Not only will Lake Tapps be a new potable water supply, but the project will improve river flows for endangered fisheries, make improvements to the Lake Tapps facilities, and continue recreational use of the lake.

Use of Lake Tapps for recreation and water supply, plus restoration of the White River fishery requires a balanced, cooperative approach. A key to ensuring that water quality remains high is on-going testing and monitoring. Cascade, Pierce County, the Muckleshoot Indian Tribe, the Puyallup Tribe of Indians and Ecology are cooperatively monitoring the water quality of Lake Tapps and the White River.

The diversion dam on the White River controls the amount of water flow into Lake Tapps and is essential in providing fish passage around the Corps' Mud Mountain Dam. The Corps has committed to continued operation and replacement of the diversion dam. Cascade is cooperating in the operational decisions regarding the diversion dam and design of the replacement dam.