There are four dams on the
main stem of the Middle Fork – at
Donnells,
Beardsley, Beardsley Forebay and Sand Bar Flat. The only significant tributary impoundment is Relief Reservoir, formed by
Relief Dam on Summit Creek. Middle Fork water is managed by the Spring Gap–Stanislaus
hydroelectric project, owned by
Pacific Gas and Electric, and the Tri-Dam project owned by the Oakdale and South San Joaquin irrigation districts.{{cite web Tunnels connect the four mainstem reservoirs to take advantage of the
hydraulic head created by the Middle Fork's steep drop. The final tunnel, from Sand Bar Flat, enters the main Stanislaus River about below the mouth of the Middle Fork, at the head of
New Melones Lake reservoir. As a result, much of the Middle Fork is dewatered during the drier months. ==See also==