McSwain
McSwain is a 9 MW hydroelectric power plant in Mariposa County, California, operated by Merced Irrigation District. EIA-860M lists 1 generating unit here, inside CAISO. Its unit entered service in 1967.
As of 2026-07 (inventory dated 2026-07-31) · EIA-860M Preliminary Monthly Electric Generator Inventory · eia.gov/…/july_generator2026.xlsx · eia.gov/…/eia860m
- Nameplate capacity
- 9 MW
- 9 MW net summer
- Generating units
- 1
- In service
- 1967
- EIA plant ID
- 410
Where it is
Loading map…
- County
- Mariposa County, California
- Coordinates
- 37.5221, -120.3101
- Balancing authority
- CISO
- Sector
- IPP Non-CHP
Units, technology and status
- Operator of record
- Merced Irrigation District
- Primary energy source
- Hydro
- Technologies
- Conventional Hydroelectric
- Status
- Operating
McSwain: FAQ
- Where is McSwain?
- In Mariposa County, California (CA). The map on this page is placed at the coordinates EIA files for the plant, which locate the site rather than any individual unit.
- How big is McSwain?
- 9 MW of nameplate capacity across 1 unit, as of the EIA-860M release for 2026-07.
- Who owns McSwain?
- EIA-860M names Merced Irrigation District as the reporting entity. That is the operator of record on the survey, which is not always the ultimate owner.
- Is this the same as McSwain LLC?
- Probably, but EIA-860M does not say. The survey records a plant name and a reporting entity — Merced Irrigation District here — not the project company that holds the asset. Project companies are commonly registered as an LLC carrying the plant's name, so a search for "McSwain LLC" usually means this site. This page shows only what EIA files, and does not assert a corporate structure it cannot see.
- Is McSwain still running?
- EIA-860M files it as "Operating" for 2026-07. Statuses change monthly, and this page follows the monthly release.