Donnells — Plant Summary
- EIA Plant ID
- 415
- Capacity
- 72 MW
- Primary Fuel
- Hydro
- Technology
- Conventional Hydroelectric
- Status
- Operating
- Location
- Tuolumne, CA
- Operating Since
- 1957
- Generators
- 1
- Operator
- Oakdale&South San Joaquin Irrigation D.
- Parent Company
- —
- Annual Generation
- 219,157 MWh
- Capacity Factor
- 34.8%
- Balancing Authority
- California Independent System Operator
- ISO/RTO
- CAISO
- NERC Region
- WECC
Donnells
OperatingHydro
Ranked #56 of 247 Hydro plants in CA#244 of 1454 nationally
72 MW Hydro operating in Tuolumne, CA — California Independent System Operator
EIAGEMWD
72 MW
Nameplate Capacity
1
Generators
unit
Conventional Hydroelectric
Technology
1957
Operating Since
Location
Coordinates
38.2467, -120.0341
County
Tuolumne, CA
Nearby Plants
- BeardsleyHydro10 MW · 6.2 km
- Spring GapHydro6 MW · 9.5 km
- Spicer Meadow ProjectHydro5.9 MW · 16.4 km
Ownership & Operator
Owner data does not fully agree across sources.
EIA typically reports the operating utility, while GEM resolves to the financial owner or parent corporation. Both can be correct.
| Field | EIA | GEM | Wikidata |
|---|---|---|---|
| Operator | Oakdale&South San Joaquin Irrigation D. | Oakdale & South San Joaquin Irrigation D. | — |
| Owner(s) | Oakdale&South San Joaquin Irrigation D. | Oakdale & South San Joaquin Irrigation D. | — |
| Status | Operating | operating | — |
Ownership Chain
GEM identifies the owner as Oakdale & South San Joaquin Irrigation D.
This entity is not yet in the GEM ownership database — chain unavailable.
About
Donnells Dam is a concrete arch dam located on the Middle Fork of the Stanislaus River in Tuolumne County, California. The water impounded by the 291-foot (89 m) high dam forms Donnell Lake in Stanislaus National Forest. The dam and reservoir are co-owned by the Oakdale Irrigation District and South San Joaquin Irrigation District, and the dam is one of three in the Tri-Dam Project. The other two dams in the project are Beardsley Dam and Tulloch Dam.
Read more on WikipediaDonnells Hydroelectric Plant is a 72 MW conventional hydroelectric facility located in Tuolumne County, California. The plant began operating in 1957 and has one generator. The primary fuel source is water (WAT). The plant is owned and operated by Oakdale & South San Joaquin Irrigation District. Donnells ranks as the 56th largest power plant in California out of 247, and 246th nationally out of 1464 plants.
In the latest year of reported generation data, Donnells produced 219,157 MWh of electricity, achieving a capacity factor of 34.8%. The plant operates within the California Independent System Operator (CAISO) balancing authority and the Western Electricity Coordinating Council (WECC) NERC region.
Generated from EIA, GEM, and public data sources
Engineering & Generators
Grid Context
NERC Region
WECC
Balancing Authority
California Independent System Operator
Grid Voltage
115 kV
Regulatory Status
NR
Entity Type
Political Subdivision
Sector
IPP Non-CHP
Generation
6.4K MWh
Latest Month
219.2K MWh
Annual Generation
34.8%
Capacity Factor
Jan 2022 – Dec 2024
Financial Data
No financial data available for this plant.
Pricing & Market Data
LOW confidenceMarket Position
ISO/RTO Market
CAISO
LMP Node
—
Pricing Hub
TH_NP15_GEN-APND
Node Source
OSM spatial match
SPRNGGP_7_B1Substation
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