The amount of water flowing into Lake Tahoe and critical western Nevada river basins is surging thanks to a parade of rain and snowstorms.
And the amount of water in storage for the Truckee Meadows is at an all-time high, although that has as much to do with deal-making among players on the Truckee River as it does with recent storms.
Still, the mix of snowmelt and rainfall that flooded the Truckee and Carson rivers in the past 48 hours is part of an ongoing series of storms that have pushed the region well above average for this time of year in terms of precipitation.
“It is pretty incredible really how much that storm added,” said Jeff Anderson, hydrologist for the Nevada Natural Resources Conservation Service, which tracks snow and water in the mountains.
For example, the amount of water stored in snow in the Tahoe Basin was 62 percent of normal on Jan. 1. In the Truckee River basin it was 84 percent of normal.
On Monday the readings showed the Tahoe Basin surged to 131 percent of normal and the Truckee River basin to 158 percent of normal. The Carson River basin jumped from 80 to 148 percent of normal.
Also, since the beginning of the water year in October, Lake Tahoe has risen about 18 inches. That’s well ahead of the rate of rise the lake typically sees between October and the traditional peak in late spring or early summer.
During the winter of 2010-11 the lake rose more than five feet, Anderson said.
“That is the kind of rise that can happen in a big year,” he said.
As far as water storage goes much of the water from recent storms surged down the Truckee River on its way to Pyramid Lake so it wasn’t captured for drinking water.
But the availability of water in general as well as the recently signed Truckee River Operating Agreement has helped the Truckee Meadows Water Authority increase the amount in storage to nearly 40,000 acre feet, the most it’s had on hand since 1985, the earliest date for which online records are available.
It’s not just water storage that’s affected. The increase in the amount of water volume locked in the snow changes the characteristics of the snowpack from powder to a denser pack often referred to as Sierra cement.
That type of snow tends to melt slower which means there could be skiing in the mountains well into the latter days of spring.
“What it is going to do is ensure a longer ski season,” Anderson said.
Meteorologist Scott McGuire of the National Weather Service said there’s nothing unusual about rain and snow hammering the Sierra Nevada during winter months.
But the most recent storm is the strongest in more than a decade.
“We haven’t seen that set up in 11 years,” McGuire said.
And there’s more to come.
The forecast for Reno calls for rain and light snow through Thursday.
At higher elevations, such as Slide Mountain where Mt. Rose Ski Tahoe is located, there is the potential for more than four feet of snow by the end of this week. An additional than three feet of snow is possible at Incline Village.
“There is an abundance of energy out in the Pacific and the jet stream is lined up perfectly,” McGuire said.
Even an incredible week of moisture, however, guarantees nothing.
If the storm door closes and the skies go dry the moisture deficit that’s marked the past several years in the Sierra Nevada could continue.
“Just like that it could dry out,” Anderson said.