“I can sign a piece of paper, but I can’t make it rain.”
—Gov. Edmund G. Brown, Jr.
California is now in its third year of one of the worst droughts in recorded history — 2013 was the driest year on record for many parts of the state, and 2014 promises to be even more parched. The unprecedented water shortage caused Gov. Brown to declare a state of emergency on Jan. 14 and to form a Drought Task Force with a charter to review water allocations and address the problem of water scarcity throughout the state. Californians in turn are being asked to voluntarily cut back on water use wherever possible, while state government agencies examine ways to move water to parts of the state where it is needed most.
Farms, ranches and dairies are being severely impacted. Half of the nation’s fruit and vegetable crop comes from California — and not surprisingly, agriculture accounts for 80 percent of all water consumed in the state. Delta farmers expecting to receive their normal allocation of water in 2014 were hit particularly hard. The Central Valley Project announced in February that agricultural users both north and south of the Delta will receive zero water allocation this year, a first for the CVP. Two NASA satellite studies of California snowpack and groundwater tables reveal the severity of the drought and why such drastic measures are required to mitigate the crisis.
NASA photos show the Sierra snowpack as viewed from space in Jan. 2013 and in Jan. 2014. The photos are self-explanatory. At the 6000-foot level and above, where the snowpack should be more than three feet deep, one now sees bare ground and pine cones. With many reservoirs around the state below 50 percent of average capacity, this means there will be little chance of replenishment with spring runoff. To exacerbate matters, if April is warm and dry, the snow will simply “sublimate,” meaning it will evaporate into the sky and blow east with the wind, leaving barely a trickle flowing into depleted reservoirs.
Other photos illustrate a dramatic impact upon California reservoirs and groundwater tables. The photo on the left shows Folsom Lake in July 2011. The photo on the right shows the lake from the same vantage point in Jan. 2014, with the lake at 17 percent of capacity. Recent rains and snowmelt have brought Folsom Lake up to 41 percent capacity, but this is still well below average. A 10-year study by a team of scientists at the UC Center for Hydrologic Modeling at UC Irvine utilized data from NASA’s Gravity Recovery and Climate Experiment — GRACE — satellite to study groundwater depletion. The data show that between 2003 and 2010 more than 30 cubic kilometers [7.2 cubic miles] of fresh water disappeared from the Sacramento and San Joaquin river basins, equivalent to the full volume of Lake Mead, and more than 20 cubic kilometers [4.8 cubic miles] of this was groundwater loss. Even though 2011 was a wet year and replenished groundwater tables back to their 2006 level, 2012 and 2013 were again dry — and in these two years alone, another 20 cubic kilometers of freshwater disappeared from these two basins, the largest drop since GRACE began monitoring California watershed data. The result is lower highs and lower lows in CA aquifers — the wet years simply do not replenish the depletion caused during the dry years.
While its reservoirs are well below capacity, the San Francisco Bay Area is nevertheless much better off than other parts of the state. The Bay Area has 17 reservoirs with a total capacity of 688,000 acre-feet [AF] of water, and a historical average of 505,000 AF. According to a California Department of Water Resources — DWR — report generated Mar 12, Bay Area reservoirs are at 394,000 AF, or about 80 percent of capacity. This is well above other California regions such as the Central Coast, which is at 31 percent of its historical average, or only 21 percent of capacity. The DWR reports similar dismal reservoir levels throughout the state, although some relief did come from the March rains.
Water rights and water allocation has always been contentious in California, and in the early 20th century even devolved into violent “water wars” — as dramatized in the quasi-historical movie Chinatown. This is due in no small part to the unequal distribution of population throughout the state combined with a widely varying climate. Specifically, whereas much of the precipitation falls in the wetter northern part of the state, much of the water is consumed in the arid desert regions to the south — and whereas the snowpack is confined to the far eastern Sierra Mountains, much of the snowmelt is used in the Central Valley and along the coasts. A hydraulic infrastructure comprising vast networks of aqueducts and pipelines was built to achieve this engineering marvel and get the water to where it is consumed.
Known to many San Francisco residents as their primary water supply, the Hetch Hetchy Project, located in Yosemite National Park, delivers 80 percent of the water used by the City and County of San Francisco. The city first secured water rights to Hetch Hetchy in 1908, over strong objections from conservationists such as John Muir and The Sierra Club. Construction began in 1914, was completed in 1923, and the first water began flowing into the city in Oct. 1934. At this time, the DWR has not published data for current Hetch Hetchy reservoir levels or its percent of capacity. However, in Jan. 2014, the San Francisco Public Utilities Commission — SFPUC — took proactive measures and passed a voluntary 10 percent cutback on all Hetch Hetchy water.
Although this is not mandatory water rationing, it could become so — as it did in the 1980s and 1990s, when statewide drought emergencies were also declared.
The early March rains were welcomed by all, but in truth they brought little real relief to the severe drought conditions throughout the state. The Sierra snowpack is only 20 percent of where it should be, and reservoir levels are still far below normal. The odds that California will be saved by a miraculous series of April storms at this point in time are close to zero. All things considered, it is shaping up to be a long, hot, dry summer, and we will have to prepare for it.
For more information on the California drought, visit the Pacific Institute’s website http://www.californiadrought.org.