Topaz Lake is a reservoir located on the California-Nevada border, about 75 miles (121 km) south of Reno. The lake was formed by diverting waters from the West Walker River into a nearby basin that had previously contained a smaller, natural lake. The initial construction took place in 1922, resulting in a reservoir with a capacity of 45,000 acre feet (56,000,000 m3). In 1937, a new levee raised the capacity to its current 126,000 acre feet (155,000,000 m3).
Topaz Lake is a relatively large with a maximum pool of 126,000 acre feet (155,000,000 m3), with 2,410 acres (9.8 km2) surface, a length of 3.5 miles, with a width of 1.5 miles and maximum depth of 92 feet. Topaz Lake is popular for boaters, water-skiers, campers, and fishermen. Fishing season runs from January 1 to September 30, and the lake is stocked with trout by the Nevada Department of Wildlife and the California Department of Fish and Game.