Monday, April 13, 2015

One Year of Water Left

Phillips Snow Field 2015

On April 1, 2015 there was no snow at an elevation of 6,800 feet in the Sierra Nevada Mountains in the Phillips Snow Field. Four times each winter the California Department of Water Resources manually surveys the Phillips and several other locations to estimate the water for the coming year. The snowpack traditionally is at its peak by early April before it begins to melt. California’s water year is determined by the measurement of the snow pack and this ceremonial measuring of the snow pack has continued even as electronic readings have become more accurate. For the first time in 75 years there was no snow in Phillips Snow Field.

California’s climate is dominated by the Pacific storm track. The mountain ranges cause precipitation to fall mostly on the western slopes. These storms also leave tremendous accumulations of snow in the Sierra Nevada during a wet winter. While the average annual precipitation in California is about 23 inches, the range of annual rainfall varies greatly from more than 140 inches in the northwestern part of the State to less than 4 inches in the southeastern part of the State in an average year. Snowmelt and rain fall in the mountains create the annual flow into creeks, streams, and rivers. California’s surface water infrastructure is designed to capture a portion of these flows. What is not captured makes their way into the valleys, much of the water percolates into the ground or. However, April 15 to October 1 is the dry season and there is no rain. What is in the reservoirs is it for the rest of the water year. After four years of drought, there is about a year of water left. If this drought doesn't end this year California will have to begin to face a new water reality.

Though the dry and snow free Phillips meadow was a show and tell media event and the first time I can recall a Governor joining the Department of Water Resources team, earlier electronic readings confirmed that the statewide snowpack holds only 1.4 inches of water content, just 5% of the historical average of 28.3 inches for April 1. The previous low for the date was 25% in 2014 and 1977. Governor Jerry Brown held a news conference in Phillips Snow Field to order cities and towns across California to cut water use by 25% as part of a sweeping set of mandatory drought restrictions, the first in California’s history. Though it is often quoted that agriculture  uses about 80% of surface water diversion in a full allocation year, that is not technically true. Approximately half of all rain and snow melt  is left to flow naturally in the state- primarily for human use though a certain base line is necessary to maintain the environment.  Forty percent of the water goes to agriculture through the Central Valley Project (CVP), State Water Project (SWP), the Colorado allocation, local reservoirs and groundwater basins. The final 10% goes to cities. The farmers dependent on the CVP and SWP will have their allocations set later this year and it is widely expected to be zero, again. The drought has not affected the state uniformly. Farmers depending on the Colorado Compact have water and frarmers with also draw from groundwater.

These water use restrictions aimed at the cities have followed recent steps to try to preserve what water California has on hand. Governor Brown declared a drought State of Emergency on January 17, 2014 and directed state officials to take all necessary actions to prepare for water shortages. He called on all Californians to voluntarily reduce their water usage by 20%, which most of the state failed to achieve. Now the restrictions are mandatory and the reduction required is 25%. If the drought does not end soon, restrictions will become rationing. In California average daily use of water by individuals on public supply is 181 gallons a day. This is more than two and a half times the per capita use in places like Virginia. This use has to be for exterior water use, watering gardens and lawns and should offer simple areas of reduction without giving up showering and laundry.

Californians have seen droughts before and each crisis has been averted by the rains finally coming before a water crisis happened. In 1995, the Pacific Institute published a report that summarized the condition of the water supply in California stating that “California’s current water use is unsustainable. In many areas, ground water is being used at a rate that exceeds the rate of natural replenishment…” In 2005 the Pacific Institute published another report. Pointing out that water demand and use continued to exceed sustainable supply. California was unmoved by these warnings.

The truth is that California has been using more water than is sustainable available to support the population, businesses and agriculture of the state, and the majority of water, (estimated at 80% of all water, but groundwater is not tracked) going to agriculture. For more than a half a century the Central Valley of California has been one of the most productive agriculture regions of the world. This has been made possible by the ample supply of cheap water used for irrigation. The limit to California’s agricultural is water availability. Water available is a combination of surface water diversions, the Colorado allocation, and groundwater pumping. Approximately one sixth of the irrigated land in the United States is in the Central Valley and approximately one eighth of all groundwater pumped in the United States is pumped in the Central Valley. California uses almost 31 billion gallons of water a day for irrigation in a “typical” year.

Only in drought years is the true stress on the system obvious. Precipitation varies widely from year to year. Multi-year droughts have occurred throughout the state’s history, as have devastating floods. In California varied climate it’s possible to have both floods and drought in the same year. California’s water system was developed over decades to address that variability and provide more reliable water supplies year-round. The original intent to smooth the variations in annual precipitation was corrupted to divert water to the most powerful. California has a long history of water wars over water rights and diversions. State officials recently projected that California’s population will reach 50 million by 2032 and 60 million by 2050. There simply is not enough water. California local water agencies have invested in water recycling, conservation, groundwater storage and other strategies to stretch supplies, but the demand has outstripped supply for over 50 years as evidenced by the groundwater usage in the central valley.
Phillips Snow Field 2014

Even without imported water Los Angeles will continue to have some water. For 30 years Los Angeles County has recycled the water from the wastewater treatments plants. This water from both secondary and tertiary treated wastewater is discharged into spreading basins to recharge groundwater. This recharged groundwater will remain available to the city to prevent disaster. However, the time will soon be here for California to make some hard decisions about the allocation and ownership of water resources and the future of the state.

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