From The Pacific Institute (Cora Kammeyer, Peter Gleick, Heather Cooley, Gregg Brill, Sonali Abraham, and Michael Cohen):
The American West has entered another drought crisis, with nearly the entire region (97 percent) facing abnormally dry conditions and over 70 percent of the region already in severe drought. State and local leaders are making emergency declarations. Water allocations are being slashed. We are already seeing fish die-offs and domestic wells running dry — and the dry season is just beginning.
There are many ways to measure drought, and all the indicators we have are telling a dismal story. Precipitation is less than half of normal across the West, and as little as a third of normal in parts of Nevada, Arizona, and California — including major cities like Sacramento, San Francisco, Las Vegas, and Phoenix. This is the second dry year in a row for California; for the seven states sharing the Colorado River, there have been two decades of below-normal water. The Sierra Nevada snowpack is essentially nonexistent, having been low all winter and now disappearing two months early. Colorado River Basin snow conditions are faring only slightly better, with snowpack ranging from 13 to 100 percent of normal across the basin states, and reservoir levels in Lake Powell and Lake Mead, the two largest reservoirs on the Colorado River, are reaching record lows. Reservoir levels in the two largest reservoirs in California — Oroville and Shasta — hover around 40 percent, far below normal for this time of year.
In response, state and federal agencies are cutting water allocations. Allocations for California’s State Water Project are at a meager five percent; the federally owned Central Valley Project allocations are at 25 percent overall but down to zero percent for agricultural contractors. On the Colorado River, unprecedented shortage declarations are looming.
Severe drought conditions like those now gripping the West have adverse consequences for people, businesses, and nature. These impacts are not evenly distributed. Small and rural communities, many of which have a greater proportion of low-income households and people of color often feel the worst effects. Freshwater ecosystems are at serious risk from low water flows and high water temperatures, and water-quality issues are worsened by increased salt and contaminant concentrations and reduced oxygen levels. Surface water shortages for agriculture lead to more groundwater pumping and continued overdraft causes land subsidence, property damage, drying of domestic wells, and a permanent loss in groundwater storage.
Fish and Wildlife: Droughts in California are especially hard on natural ecosystems, already suffering from overuse and contamination. In 2014 and 2015, 95 percent of young, endangered winter-run Chinook Salmon died due to high water temperatures on the Sacramento River, increasing the risk of regional extinction of already threatened salmon and other fish species.
Wildfire: Wildfires are already becoming more frequent and severe, and they are starting earlier in the year and lasting longer. Low soil moisture and lack of rain worsens pest outbreaks and tree deaths, which in turn further increases wildfire risks and concern is growing for an extremely severe fire risk this year.
Agriculture: In the face of water shortages, farmers have to look to alternative supplies and practices, such as purchasing water through temporary transfers, pumping more groundwater, changing the types of crops grown, installing efficient irrigation systems, and fallowing land. As efforts to implement California’s Sustainable Groundwater Management Act (SGMA) expand, constraints on groundwater pumping — in both wet and dry years — will grow, further complicating agricultural responses to drought.
Rural Communities: Rural communities throughout the west are often dependent on a single water source, which increases their vulnerability to drought. During the past severe California drought, many shallow rural groundwater wells went dry as deeper agricultural wells depleted groundwater, causing major impacts on some communities. Declining water supplies and water-quality problems this year may force communities to switch to costly bottled water, dig deeper wells, and truck in emergency supplies of water. These actions impose local economic hardships on those living in rural areas, many of whom are among our most disadvantaged communities.
Urban Areas: A diversified water supply means that urban areas are usually not at high risk of running out of water, but severe drought typically leads to voluntary and mandatory efforts to cut use. There is capacity to create additional supply through water conservation in these areas. Water utilities are already beginning to implement mandatory and voluntary water-conservation programs, including educational programs, incentives to install water-efficient devices, and restrictions on discretionary water uses like car washing and watering lawns, and new cutbacks are likely as the drought continues.
Energy: Drought can strain the energy system. Past droughts have led to declines in hydroelectricity generation, leading to a shift to more expensive and polluting fossil fuels. Electricity generation from thermoelectric plants may also be curtailed if insufficient cooling water is available or if temperature limits in receiving waters are exceeded. Pumping costs to farmers increase as groundwater levels drop. Additionally, higher temperatures associated with drought reduce the efficiency of thermal power plants and of transmission and distribution lines while increasing energy demand for cooling systems.
The good news is that past experience has shown there are many appropriate and effective responses to droughts, including changes in the efficiency of urban and agricultural water uses, the expansion of non-traditional water sources like stormwater and recycled water, and voluntary changes in behavior – all of which can help lessen the severity of this drought and future ones. In future blog posts and research, the Pacific Institute’s Western Drought Initiative will offer information on these responses, building on previous work and experience around drought impacts and solutions. Stay tuned for more coverage to come and for up-to-date drought conditions for California, visit http://www.californiadrought.org. For publications on these issues, including previous drought work, visit http://www.pacinst.org/publications.