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Update on the California Drought – June 21, 2016
From the Pacific Institute’s California Drought Response Team
Potentially One of the Worst Wildfire Seasons Ahead
The National Interagency Fire Center predicts that the ongoing drought will significantly increase fire potential, especially in Southern California. In an effort to mitigate risk, the Los Padres National Forest recently increased fire restrictions to Level III, which prohibits wood and charcoal fires in all areas of Los Padres National Forest except for developed campgrounds. Earlier in June, the Calabasas fire, which consumed more than 500 acres, prompted an evacuation of about 5,000 people in the Topanga Canyon and Mulholland Highway area around Calabasas.
Currently, California is experiencing three large fires (as of June 20, 2016):
- The Sherpa fire in Los Padres National Forest is affecting 7,893 acres, and is 54% contained.
- The Pony fire in Klamath National Forest is spreading across 2,855 acres, and is 60% contained.
- The Soda fire in San Luis Obispo County is affecting 2,005 acres, and is 95% contained.
California will likely experience a more active fire season this year. Cal Fire has estimated that drought and bark beetle infestation have caused the death of over 29 million trees, an increase from 3.3 million trees in 2014 (water-starved trees are especially vulnerable to drought beetle infestation). These dead and dying trees increase the risk of fire across the state.
In Other News
- The State Water Resources Control Board dismissed fines for unauthorized water diversions they had levied on Byron-Bethany Irrigation District and West Side Irrigation District. They cited a lack of adequate evidence to justify the cease-and-desist order as reason for the dismissal.
- California’s 3rd District Court of Appeal temporarily suspended the Metropolitan District of Southern California’s $175 million purchase of Delta islands to allow more time to consider evidence. San Joaquin and Contra Costa counties requested this judicial process given concerns relating to the construction of the Delta tunnels, which would convey water from the Sacramento River to Southern California.
- The Metropolitan Water District of Southern California, the region’s largest wholesale water supplier, announced that it has enough water to last for the next three years, even if the current drought continues. The analysis was a response to the State Board’s requirement to conduct a “stress test” to determine the need for conservation.
- The US Geological Survey released a new online interactive tool that provides summaries of decadal-scale changes in groundwater quality across the nation. The map highlights groundwater quality concerns in California, especially for nitrate, chloride, and total dissolved solids.
- On June 9, the National Weather Service declared that El Niño has dissipated. ENSO-neutral conditions are present with a 75% chance of La Niña development during the upcoming fall and winter. ENSO-neutral conditions refer to periods when the ocean temperatures, tropical rainfall patterns, and atmospheric winds over the equatorial Pacific Ocean are near the long-term average.
- The State Board reported that water conservation increased to 26.1% across the state in April over 2013 usage, but stressed that water suppliers must continue to make conservation a top priority amidst ongoing drought conditions in many parts of California.
- Scientists at the University of California’s West Side Research and Extension Center found that, for some crops, overhead irrigation systems can produce the same or increased yield as furrow or drip irrigation. Overhead irrigation systems are currently only used on about 2% of California’s irrigated acreage.
- San Joaquin County’s groundwater report to the Advisory Water Commission reveals that water levels in that county have dropped about two feet on average over spring 2016, less than the 3-foot drop experienced in spring 2015.
California Drought Status
The severity of drought conditions has remained relatively the same over the past two weeks. About 43% of the state is under severe-to-exceptional drought, similar to two weeks ago. Areas under moderate-to-severe drought are about 42%.
The state’s water supply may appear to be in a good condition at the moment, but rapid snowmelt may affect supplies later in the summer.
The Sierra snowpack is at 6% of normal as of its normal level as of June 13, a decrease of 17 percentage points since June 1. The Central and Southern Sierra reporting stations are now clear of snow. See these snowpack plots for changes over time.
Cumulative precipitation is still about average in the San Joaquin region, at 40 inches since the beginning of the water year (October 1), and above average in the Northern Sierra region at 57.8 inches. However, cumulative precipitation is currently below average in the Tulare Lake Basin at 25.7 inches.
Over the past two weeks, water levels in California’s major reservoirs (representing 27.3 million acre-feet of storage) slightly fell to 64% of statewide capacity. These levels represent 86% of reported average for June 5. Lake Oroville, Shasta Lake, and Folsom Lake are now at 107%, 107%, and 95% of historical average, respectively. However, New Melones Lake, another major reservoir with a 2.4 million acre-feet capacity, remains at 42% of historical average.
The most recent data on groundwater conditions are based on measurements taken in fall 2015. Maps of spring and fall groundwater level changes can be found here and a map highlighting significant changes is available here. Areas with the greatest concern, where groundwater levels have declined by more than 100 feet, can be found in parts of the Tulare Lake, the South Coast, and the Colorado River hydrologic regions.
Read past updates here
- California Data Exchange Center, including a water supply and drought information summary, by the California Department of Water Resources.
- “One-stop shop” for water data and maps by the National Oceanic and Atmospheric Association (NOAA).
- Groundwater Information Center (GIC) interactive map by the California Department of Water Resources.
- Interactive tool of changes in reservoir storage levels since January 2010 by KQED News.
- River conditions by the California Nevada River Forecast Center.
- Interactive map of residential and system-wide water use by the Pacific Institute.
- Western Regional Climate Center’s (WRCC) climate anomaly maps and tables for California.