Lake San Cristobal

Lake San Cristobal is the second largest natural lake in the U.S. state of Colorado. Located in the San Juan Mountains at an elevation of 9003ft, the freshwater lake is 2.1mi long, up to 89ft deep, has a surface area of 0.52sqmi, and holds about 11000acre.ft of water. The town of Lake City, a few miles to the north, is named after Lake San Cristobal. The name San Cristóbal means Saint Christopher in the Spanish language.GeologyLake San Cristobal was formed about 700 years ago when the first Slumgullion Earthflow, a natural landslide, created a dam across the Lake Fork of the Gunnison River. Natural landslide dams are usually short-lived, but some have been known to fail after long periods—131 years in the case of Lake Yashinkul in the former Soviet Union. This prompted the United States Geological Survey to investigate the possibility that the Lake San Cristobal dam might fail. Based on its non-porous composition and the fact that part of the dam's natural spillway is actually cut into bedrock and not the material deposited by the landslide, the USGS concluded the dam stable. Sediments washing down via the Lake Fork and Slumgullion Creek are slowly filling in the lake, but are not expected to affect the dam's stability. If sedimentation continues at the past rate, the lake will have completely filled with sediment in about 2,500 years.