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Tahoe Nugget #9:
Tahoe Dam 1997 Flood
The Lake Tahoe Dam is a classic example of human hubris. Tahoe is a large alpine lake 22 miles from north to south and up to 12 miles wide. At
1,645 feet deep, it is the tenth deepest lake in the world. There are about 63 streams that feed the lake, but the only outlet is the Tahoe City dam with its 17 small gates.
The first dam was established in
1870 with the intent to divert water to San Francisco in a massive public works project that engineer Alexis Von Schmidt called the "greatest aqueduct in the world." Fortunately for Lake Tahoe, the plan
fell through due to its $10 million cost and state politics. Years later, in another controversial move, San Francisco tapped Yosemite's stunning Hetch Hetchy valley for it's primary water supply, an act which broke
environmentalist John Muir's heart.
Against the better judgment of many 19th century pioneers, at the turn of the last century the U.S. government established Lake Tahoe as a reservoir for downstream users
in Nevada with a storage capacity of six feet. Historically, the lake would rise and fall about 15 feet depending on weather conditions, so early settlers claimed that six feet of storage was insufficient. They
insisted that during years of dry weather the lake would fall below its rim at 6,223 above sea level and stop feeding the Truckee River which supplies Reno with more than 80% of its water, while a series of wet
years or a season with major storms the lake could exceed the lake's "legal" maximum level of 6,229 feet. As predicted, both events have occurred in the last 100 years.
A major flood situation
developed in December 1996 when a series of wet Pacific storms quickly filled Lake Tahoe beyond its maximum limit by 3 inches or so, and the Federal Watermaster Garry Stone was forced (by law) to open all the
Tahoe gates and inundate Reno. The resulting flood caused $650 million in damages. Ironically, the current legal arrangement contains no provisions for protecting communities in the Truckee River floodplain if Tahoe
water levels are too high. Until changes are made in the law, Reno will continue to be flooded out to protect even minimal shoreline erosion in the Tahoe Basin. I took this photo in January 1997 when all gates
in the Tahoe dam were wide open and the river was running at record flow for several weeks.
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