Tahoe Nugget #73:
Hazardous Spring Snowmelt (4 Photos)
May 12, 2006
The National Weather Service is warning people to beware of dangerous conditions on western streams and rivers. A very cool and wet spring delayed the spring snow melt, but now warming temperatures have accelerated
the mountain snowpack runoff, generating high and potentially deadly river stages.
The exceptional river flows are no surprise. As of May 1 water content in the Tahoe Basin snowpack was 173% as a result of
the very wet winter. The only month during this past winter that did not produce above-normal precipitation was February. April was another extraordinary month with the Truckee River Basin receiving 283% of
precipitation. Reservoir storage in Lake Tahoe and the Truckee River Basin is currently at about 140% of average. Although the Humboldt River in northern Nevada has been in flood stage for the last six weeks, melt
in the Central Sierra did not get going until early May. Stream flow forecasts for the Truckee River indicate that water will be flowing at more than 150% of normal for the foreseeable future. Water storage in Lake
Tahoe has greatly increased. At this time last year, the usable storage in the lake was 98,300 acre-feet of water, this year it's 556,000 acre-feet. (An acre-foot is enough water to cover an acre of land with 12
inches, nearly 326,000 gallons)
Warming air temperatures and high water inspires kayakers, boaters and swimmers to hit regional streams and rivers. Every spring, people underestimate the power of fast water
and lose their lives. The NWS is alerting people to extremely dangerous river hazards associated with this year's high water levels and strong river currents. Fast water need only be a few inches deep to sweep
you off your feet and carry you downstream. With water temperatures in the 40s and 50s, hypothermia will set in quickly with a sudden loss of body temperature that can be fatal. Warning signs of hypothermia include
uncontrolled shivering, memory loss, disorientation, incoherence, slurred speech, drowsiness and exhaustion.
Photo #1: Water flowing over the top of Eagle Falls above Emerald Bay.
Photo #2: Spring
snowmelt out of the Sierra is frigid, fast and potentially deadly.
Photo #3: Sacramento County safety teams practice water rescue in American River. Men are holding each other to help balance themselves in
strong current. Note dry suits to protect from very cold water.
Photo #4: When things get really bad, they send in the canine rescue team!