Welcome to the Tri-Dam Project

Tri-Dam Project is a partnership between the Oakdale Irrigation District and the South San Joaquin Irrigation District. Together they developed, operate and maintain the Beardsley, Donnells and Tulloch projects including the dams, tunnels, penstocks, power houses, communications systems, and general offices. These facilities are located on the Middle Fork of the Stanislaus River in Tuolumne County, California.

The "Upper Works" include Donnells and Beardsley dams, reservoirs, power houses and appurtenant facilities. The "Lower Works" refer to the Tulloch development below Jamestown reaching into both Calaveras and Tuolumne Counties.

Tri-Dam Project is governed by a joint board of directors composed of the five member boards of the two Districts. The day to day activities of Tri-Dam Project and Tri-Dam Power Authority are managed by a General Manager who reports to the board. The administrative offices of Tri-Dam Project are located in Strawberry, California.

Dam Good Photos Beardsley DamDonnells DamTulloch Dam

Special Notes:

Draft Aquatic Vegetation Management Plan

Tri-Dam is responsible for management and operation of Tulloch Reservoir under the provisions of a license issued by the Federal Energy Regulatory Commission (FERC). Part of this license requires that Tri-Dam prepare an Aquatic Vegetation Management Plan to provide information and guidance regarding the potential treatment of various aquatic vegetation species within Tulloch Reservoir. Tri-Dam retained JR Holeman Consulting to assist in the preparation of an Aquatic Vegetation Management Plan. At the beginning of this process, all homeowners associations, state and federal agencies and other interested persons were invited to participate in the development of this plan. The draft Plan was prepared with input from the State Water Resources Control Board, University of California Cooperative Extension Service, Tuolumne County, and representatives from homeowners associations at Tulloch Reservoir and is intended to comply with FERC requirements.

Tri-Dam welcomes your review of this plan as we work toward cooperative reservoir management. Comments are requested within 30 days. Please email your comments to Susan Larson at slarson@tridamproject.com and copy Jim Holeman at jholeman1@gmail.com, or mail them to Susan Larson, License Compliance Coordinator, PO Box 1158 Pinecrest, CA 95364.

Please visit the Summit Ranger District website at http://www.fs.usda.gov/recmain/stanislaus/recreation for Donnells and Beardsley Reservoir recreation information. For recreation information at Lake Tulloch please visit: http://www.laketullochcampground.com/.

The Tulloch Reservoir Operating Schedule for 2013/2014 is now available on the Tulloch page.

Save the STAN Please visit Save the STAN, a public education effort of South San Joaquin and Oakdale Irrigation Districts.

Data for July 29
Click below for historical data

Elevation (feet above sea level)
3,311.69 Beardsley
4,908.05 Donnells
509.52 Tulloch
Storage (acre feet)
44,252 Beardsley
61,377 Donnells
66,369 Tulloch
Outflow (cubic feet/sec)
Road Conditions
Current road conditions to Beardsley and Donnells Reservoirs can be found on their respective pages.