LAKE TAHOE, Calif. – After silver was discovered in Virginia City in 1859, it became a boomtown after a massive influx of miners and speculators arrived to make it rich. To supply water to the town and the mines, Marlette Lake was created by installing a dam on what was known as Goodwin Lake, and Hobart Reservoir was created. The water was diverted to Virginia City via an ingenious system of flumes and pipelines, including the world’s largest inverted siphon in 1873. This included a 3,994-foot-long tunnel through the watershed basin divide, and an ingenious inverted siphon pipe to get water through Washoe Valley. 

The Marlette Lake Dam is a National Landmark and is on the National Register of Historic Places.

The same system supplies water to Virginia City, Storey County, and Carson City, but there is a project underway to fix the 152-year-old dam, known as the Marlette Lake Dam project. Seepage was found at the dam during an inspection in 2017, and it was determined that this seepage could eventually lead to a catastrophic failure.

The Marlette Lake Dam Rehabilitation was recently kicked off with a ceremony including all the involved agencies and partners. It is funded by the FEMA Pre-Disaster Mitigation Fund and will improve the overall safety of the earthen embankment dam and ensure the longevity of the water resource. Environmental and cultural resource surveys were completed in the four-year planning span of the project in coordination with FEMA. The project is planned to end in October 2026.

The Marlette Lake Water System, encompassing Marlette Lake, Hobart Reservoir, and several catchments on the east slope of the Sierra Nevada mountains above Washoe Valley, is all part of the improvement project, and public access will be limited. The enhancements will address issues with the current system as well as expand capacity.