page_title: Putah Creek
section_title: Dams and diversions
hierarchical_section_title: Putah Creek / Dams and diversions
caption_attribution_description: English: Aerial view of the Monticello Dam.
context_page_description: Putah Creek is a major stream in Northern California, a tributary of the Yolo Bypass, and ultimately, the Sacramento River. The 85-mile-long creek has its headwaters in the Mayacamas Mountains, a part of the Coast Range, and flows east through two dams. First, Monticello Dam forms Lake Berryessa, below which Putah Creek forms the border of Yolo and Solano Counties, and then flows to the Putah Diversion Dam and Lake Solano. After several drought years in the late 1980s, the majority of Putah Creek went dry, prompting a landmark lawsuit that resulted in the signing of the Putah Creek Accord in 2000. The Accord established releases from the dams to maintain stream flows in Putah Creek, with natural flow regimes which spike in winter/spring and ebb in summer/fall. The restoration of natural flow regimes has resulted in a doubling of riparian bird species and a return of spawning native steelhead trout and Chinook salmon, as well as protecting the livelihood of farmers on the lower watershed.
context_section_description: Monticello Dam, a concrete arch dam, is the only major storage dam on the creek. It forms Lake Berryessa, which has a capacity of 1,602,000 acre feet (1.976×10⁹ m³), making it one of the largest reservoirs in the state of California. The dam and lake are part of the United States Bureau of Reclamation's Solano Project and was completed in 1957. The project's purpose is to provide water for irrigation, though it also supplies municipal and industrial water to major cities in Solano County. About 32,000 acre feet (39,000,000 m³) is provided by the project annually. An 11 MW hydroelectric plant generates electricity for the Solano Irrigation District, which owns and operates the dam.
  The Putah Diversion Dam, or PDD, also constructed in 1957, diverts water into Putah South Canal about 6 miles (9.7 km) downstream of Monticello Dam. The dam is a gated concrete weir structure with an earth-fill embankment wing. It creates the small Lake Solano, which has a capacity of only 750 acre feet (930,000 m³). The canal is entirely concrete-lined except for a mile (1.6 km) of pipe called the Putah South Pipeline. Most of the lands are below the level of the canal and are served by gravity. Lands above pump water straight from the canal. The canal ends at Terminal Dam, which is made from earth-fill. The dam forms a small 119 acre foot (147,000 m³) reservoir called Solano Lake. This reservoir supplies drinking water to the city of Vallejo. Most of the canal is operated by Solano Irrigation District, including its headworks.
caption: Monticello Dam, aerial view