The dark blue, saline waters of Mono Lake are featured in this low-oblique, northwest-looking photograph. Mono Lake, approximately 14 miles (23 kilometers) long and 9 miles (14 kilometers) wide, is fed by springs that rise through beds of saline sands. Visible are the snow-covered Sierra Nevada Mountains to the west and the Excelsior Mountains to the north and east. Because the lake has supplied water for the growing population of Los Angeles for the last 10 to 20 years, the ecosystem of the lake and its surrounding habitat are at risk if water conservation measures are not implemented.