According to the Colorado Lake and Reservoir Management Association (CLRMA), Barr Lake in Colorado has been described as an oasis throughout its history. The area around Barr Lake became a Colorado state park in the 1970s.
According to the Sangres website, Barr Lake is located northeast of Denver and receives water from the South Platte River. The lake is owned and operated by an irrigation company, to supply water to farmers in the area and supply drinking water to residents of Colorado.
Barr Lake was originally known as Oasis Reservoir, supplying water for wild buffalo and, in the 19th century, to cattle driven up from Texas. The CLRMA reports that the reservoir was expanded to double its original size in 1908 and was renamed Barr Lake.
By the 1960s, Barr Lake was polluted to such an extent that it had been labeled the largest inland sewage lagoon in the United States. The creation of a water-treatment facility on the South Platte River improved the water quality greatly, allowing the water of Barr Lake to be used as drinking water again by the 1990s.
