[5][6] Donnells Reservoir, along with the two other dams of that make up the Tri-Dam Project, currently provide water for the irrigation of about 117,500 acres (47,600 ha) of farmland in Stanislaus and San Joaquin counties.

[10] As part of the agreement, Donnells and Beardsley reservoirs had to be used for power generation except in the case that water had to be released to enhance downstream flows.

[10] After the rights claims issues were resolved, the districts set out to find funding for the project and, after much difficulty, settled on selling bonds.

The OID and SSJID, with the help of Pacific Gas and Electric Company (PG&E), successfully sold bonds to fund the Tri-Dam Project and started construction of the dams in 1955.

Additionally, the dam is located in a steep, rocky canyon and offers several forms of recreation, including fishing, hunting, boating, camping and hiking.