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:

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 Fall/Winter 2014-2015 Tulloch Drawdown Schedule 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 October 21
Click below for historical data

Elevation (feet above sea level)
3,299.96 Beardsley
4,852.42 Donnells
502.80 Tulloch
Storage (acre feet)
38,119 Beardsley
39,559 Donnells
58,386 Tulloch
Outflow (cubic feet/sec)
Road Conditions
Current road conditions to Beardsley and Donnells Reservoirs can be found on their respective pages.