From the Sierra to the sea this winter’s El Nino storms are boosting both water supplies and people’s spirits in Central California.

From the top at Farewell Gap in Sequoia National Park (pictured above) to the well named Irish Hills in San Luis Obispo County the wet pattern we’ve seen since October is reminiscent of 1998 when the state saw above normal rain and snowpack.

This year the El Nino pattern has steered storm after storm into both northern and central California with more rainy days the region has seen in many moons.

The water is welcome relief after three years of drought in the state causing economic havoc when there is already  plenty of havoc without water worries.

So, is the big drought over?

It’ s the first week of March and Shasta Dam - at the top of California’s massive hydraulic storage and delivery system - already has seen more rain than it did last year by October 1. Shasta is now at 103% of March 1 average and 93% of April 1 average - the time when most rain or snow is laid down.

The Central Valley Project that depends on Shasta and other big reservoirs is now expecting to to deliver 96% of average.

To add to what has fallen already consider NOAA’s Climate Prediction’s expectation that March will be another wet month with near term forecast in the next week  including several potent storms.

If northern California is  above average for this time of the year the news is even better in the south/central part of the state. The California Department of Water Resources reports that the San Joaquin Basin that feeds the east side’s Friant Kern Canal is 119% of average for March 1 and 103% of April1 average.

Further south in the Kaweah Basin we are at 139% of March1 average and 124% of April1 average meaning farmers in Tulare/Kings should have a good river run this year.

There are some amazing numbers on the Tule this March where snow water content in the upper watershed has reached 43 inches with the historical April1 average just 12.3. State DWR says the Tule basin is 339% of average for March 1 and 301% of April1 average.

Unfortunately Success Dam on the Tule can not hold a full allotment this year or any time soon unit seismic improvements are completed some years from now.

Farmers are not the only ones cheering about river runs with Three Rivers’ daredevil kayakers  making white water river runs very early this spring with the high flows. “Some days the river is really roaring” say one local.

Green Foothills

If there is good news in the Sierra and San Joaquin Valley the storms have not be stingy heading east from the Pacific either as two months of wet weather have greened up the central coast foothills to look like Ireland. On a practical scale the storms have done wonders for key reservoirs in SLO.

Lake Nacimiento sits at 765ft elevation at press time- up 4ft this week and at 55% of  capacity.. The lake located in Monterey County seldom gets  above 800 ft elevation but this year it could as storms have dropped  their loads again and again on the surrounding  watershed this season.

Nacimiento’s 55% capacity compares to just 16% last fall says San Luis Obispo County public works engineer Carolyn Berg. Rainfall has been impressive this year - nearly 20 inches as of March 3 2010 compared to 9.77 inches for the same date in 2009. The filing of Nacimiento Reservoir is important here given the fact that the long awaited construction project to bring Nacimiento water to San luis Obispo is set to begin deliveries late this year. “These storms are coming at the right time” smiles Berg who helps oversee the construction of the 45 mile pipeline project.

“The new water will be welcome since SLO county depends on 80% groundwater use” notes Berg. “Our leaders since the 1950s had great foresight to preserve these water rights.”

Up at Santa Margarita the reservoir is 103% of capacity with some 31 inches of rain in the bucket so far this year. The lake provides drinking water for the City of San Luis Obispo. Other areas  of the central coast are either near normal or above average.

Sober Up

Still water worries continue for many users.

The Department of Water Resources  increased anticipated 2010 State Water Project deliveries to California’s water contractors from five to 15 percent of requests in recent days. If this amount remains unchanged by the final allocation in late spring this will be the lowest allocation percentage in the project’s history.

“Despite a relatively wet winter our reservoir storage levels remain low,” said DWR Director Mark Cowin. “After three years of drought conditions and a number of mandated pumping restrictions even a wet year won’t get us out of the woods. We need increased conservation, a more reliable water delivery system and a comprehensive solution for California’s water crisis.”

Lake Oroville is at only 54% of its average storage level for this time of year. And while San Luis Reservoir is at 80% of normal for this time of year, the vast majority of that supply is unavailable for this year’s allocation. Most of the supply in San Luis is earmarked for individual water contractors who are trying to stretch these supplies carried over from previous years. So supplies in two key State Water Project reservoirs are well below where DWR would like them to be.

Another hydrologic condition affecting the allocation amount is the condition of the watershed.After three years of drought, the watershed is dry and will likely absorb more of the snowpack. Therefore, less runoff from the snowpack is expected.

However, the allocation at this time of year is a conservative estimate. As winter progresses and the Department has a clearer picture of water conditions, the allocation can be increased. There is a 90 percent chance that the allocation will improve by late spring. If average precipitation continues, the final allocation will likely be in the range of 35-45 percent of requested amounts. That spread is based on how the biological opinions to protect fish species are applied and how much flexibility the Department has to pump water.

In 2009, the State Water Project delivered 40 percent of customer requests. The federal Central Valley Project was only able to deliver 10 percent of contracted amounts to some agricultural areas in the San Joaquin Valley.