or PCBs found in local species. Stormwater runoff from a nearby Superfund site formally known as the Laboratory for Energy-Related Health Research (LEHR), has shown elevated levels of Mercury reaching 500 ng/L entering Putah Creek. While the site has been decommissioned since the late 1980s and federally listed as a National Priority Superfund site by the EPA in 1994, the amount of contamination to the soil, groundwater aquifer, and nearby Putah Creek, continue to be a hazard to the area. This concentration of mercury in Putah creek creates health risks for anything that may eat the fish, as the bioaccumulation of mercury found in the fish passes along the food web to birds and potentially humans. The stream continues east along State Route 128, receiving Pleasants Creek before arriving at Lake Solano where the Putah Diversion Dam diverts flows to the Putah South Canal, carrying water to the residents of Vallejo. Below Lake Solano, Putah Creek flows before reaching the Yolo Bypass and by that artificial route, to the Sacramento River. In this section, Putah Creek first receives McCune Creek, then its last tributary, Dry Creek. After the Dry Creek confluence it passes through the town of Winters to reach Interstate 505. From there Putah Creek channel continues eastward, parallelling Putah Creek Road to Stevenson Bridge Road. Putah Creek used to flow near downtown Davis in what is now the UC Davis Arboretum channel, but early settlers redirected the creek south of Davis in 1871, and in the late 1940s the Army Corps of Engineers added levees to what is now the South Fork Putah Creek. A few miles east of Davis, the county line turns south, but the South Fork Putah Creek continues eastward, passing south of Davis to feed into the Yolo Bypass about a quarter mile (400 m) west of the Sacramento Deep Water Channel. Dams and diversions Monticello Dam, a concrete arch dam, is the only major storage dam on the creek. It forms Lake Berryessa, which has a capacity of , 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 is provided by the project annually. An 11