Topaz Lake is a census-designated place (CDP) in Douglas County, Nevada, United States. The population was 157 at the 2010 census. Geography The CDP is located on the northwest shore of Topaz Lake just north of the California border. U.S. Route 395 runs through the community, leading north to Carson City and south to Mono Lake in California. According to the United States Census Bureau, the Topaz Lake CDP has a total area of , of which is land and , or 29.87%, is water. Demographics References Census-designated places in Douglas County, Nevada Census-designated places in Nevada es:Topaz Lake (Nevada)