Governor Jerry Brown of California calls for mandatory water cutbacks of 25% in comparison to a baseline of 2013 usage:
With new measurements showing the state’s mountain snowpack at a record low, officials said California’s drought is entering uncharted territory and certain to extend into a fourth straight year. As a result, Brown issued sweeping new directives to reduce water consumption by state residents, including a mandatory 25 percent cut in urban water use.
On Wednesday, Brown attended a routine snow survey at 6,800 feet in the Sierra Nevada, near Echo Summit on Highway 50 along the road to Lake Tahoe. The April 1 survey is an annual ritual, marking the end of the winter season, in which automated sensors and technicians in the field strive to measure how much water the state’s farms and cities will receive from snowmelt.
The measurements showed the snowpack at just 5 percent of average for April 1, well below the previous record low of 25 percent, which was reached last year and in 1977.
California’s mountain snowpack is crucial to determining summer supplies, normally accounting for at least 30 percent of total fresh water available statewide. The poor snowpack means California reservoirs likely already have reached peak storage and will receive little additional runoff from snowmelt, an unusual situation.
Snowpack 5% of normal may be indicative of climate change, rather than chance deviation. Brown certainly seems to think so:
“I would hope that we don’t see this in some punitive way, but that we see the challenge,” Brown said. “(The) reality is that the climate is getting warmer, the weather is getting more extreme and unpredictable, and we have to become more resilient, more efficient and more innovative. And that’s exactly what we’re going to do.”
California residents curious about water resources may use the Water Education Foundation website to learn more.
Of interest is the Colorado River:
California is entitled to 4.4 million acre-feet of water annually from river. Most of that water irrigates crops in the Palo Verde, Imperial and Coachella valleys, located in the southeastern corner of the state, but the Colorado also is a vital source of water for urban southern California.
And water stored in aquifers:
About 30 percent of California’s total annual water supply comes from groundwater in normal years, and up to 60 percent in drought years.
Aquifers do not necessarily recharge quickly, so they cannot be regarded as eternal. They can also become contaminated by pollution and other sources, although I do not know whether California supplies are vulnerable.
Water is also transported within the state to supply population centers. Given the large population, the drop off in usable precipitation (that which runs off into the ocean may not be usable) and recent inclination towards drought, and the State is looking at quite the challenge. The Colorado River usage itself may not be sustainable, as suggested by a recent government study:
It is widely known that the Colorado River, based on the inflows observed over the last century, is over-allocated and supply and demand imbalances are likely to occur in the
future. Up to this point, this imbalance has been managed, and demands have largely been met as a result of the considerable amount of reservoir storage capacity in the system, the fact that the Upper Basin States are still developing into their apportionments, and efforts the Basin States have made to reduce their demand for Colorado River water.Concerns regarding the reliability of the Colorado River system to meet future needs are even more apparent today. The Basin States include some of the fastest growing urban and industrial areas in the United States. At the same time, the effects of climate change and variability on the Basin water supply has been the focus of many scientific studies which project a decline in the future yield of the Colorado River. Increasing demand, coupled with decreasing supplies, will certainly exacerbate imbalances throughout the Basin.
