Abstract 

This Cascades Diversion Dam Removal Project Environmental Assessment is intended to guide the removal of Cascades Diversion Dam. The project and its environmental assessment, which evaluates the potential impacts of the project, are integrated in this document and are referred to collectively as the Cascades Diversion Dam Removal Project Environmental Assessment. The Cascades Diversion Dam Removal Project Environmental Assessment identifies and analyzes three alternatives: Alternative 1 – the No Action Alternative; Alternative 2 – Complete Dam Removal (the “preferred alternative”); and Alternative 3 – Partial Dam Removal.

Alternative 1, theNo Action Alternative, represents conditions and management practices as they currently exist at Cascades Diversion Dam. It provides the basis for comparison of each action alternative. The action alternatives (Alternatives 2 and 3) are based on the Purpose Of and Need For the Project and conform with the goals of Yosemite National Park’s General Management Plan and goals and management elements of the Merced Wild and Scenic River Comprehensive Management Plan and the Yosemite Valley Plan. The alternatives vary in the ways they accomplish these goals.

Alternative 2 includes the complete removal of the diversion dam and attendant structures, bank stabilization, and site restoration. This alternative would remove all structural features exposed to public view, including the river-left and river-right dam abutments, the intake structure, and the screenhouse. Alternative 3 would partially remove the diversion dam and attendant structures and would include bank stabilization and site restoration. Under Alternative 3, the river-right dam abutment and the intake structure would be retained as a river-viewing platform. All other structures would be removed.

Written comments regarding this document should be directed to:

Mail:          Superintendent, Yosemite National Park

                    ATTN.: Cascades Diversion Dam Removal Project

                    P.O. Box 577

                    Yosemite, California 95389

Fax:            209/379-1294

Email:       Yose_Planning@nps.gov 

Written comments will also be accepted at the National Park Service planning open house held on February 26, 2003 (2:00 p.m. to 6:00 p.m.) at the Yosemite Valley Visitor Center East Auditorium. Planning teams will be on hand to answer questions and provide more information regarding the Cascades Diversion Dam Removal Project, as well as several other Yosemite National Park planning efforts.

To request a printed copy, refer to the information directly above or phone 209/379-1365