Current Conditions

Click on the images below to see the full-size version. 

US Seasonal Drought Outlook

US Seasonal Drought Outlook
(through 10/31/16)  
Source: NWS


Update on the California Drought: July 11 – 22, 2016

From the Pacific Institute’s California Drought Response Team

Top Story

Algal Bloom in California’s Lakes

Drought-related factors, such as warmer temperatures, reduced flows, and high nutrient concentrations, have caused a number of toxic algal blooms across California. Since early summer, local officials have warned against human and animal contact with or use of untreated water in several Northern California water bodies, including the Iron Gate and Copco Reservoirs on the Klamath River and Lake Temescal in Oakland. The problem is becoming more widespread, with a series of warnings in July. The affected lakes and reservoirs include Pyramid Lake in Los Angeles County and the Pit River Arm of Shasta Lake and Lake Britton in Shasta County.

The blue-green algae, or cyanobacteria, produce toxins that can harm human health. Exposure from skin contact, swallowing, or inhaling the spray can cause rashes, mouth ulcers, vomiting, diarrhea, and cold- or flu-like symptoms. Common water purification techniques, such as camping filters, tablets, and boiling do not remove toxins. Officials have also warned against eating fish and clams from the affected water bodies and permitting pets to swim in the water or drink it.

In Other News

  • The California Department of Public Health reported an increase in West Nile Virus (WNV) activity across the state. While the first human case has not been confirmed, a resident of Los Angeles County has symptoms consistent with West Nile Virus disease. Some public health officials and scientists have suggested that the drought may be linked to a rise in WNV prevalence; reduced flows create pools of stagnant water, and limited water sources leads to more interactions between birds and WNV-carrying mosquitoes.
  • The latest El Niño-Southern Oscillation forecast suggests a reduction in the probability of La Niña developing during the fall and winter of 2016-17. The current prediction shows a 55-60% chance, compared to the 75% chance predicted in May 2016.
  • Stanford researchers recently published a new study that highlights the costs and benefits of using groundwater recharge and storage across the state. The study reveals that the median cost of managed aquifer recharge (MAR) projects is $410 per acre-foot, compared to the more expensive surface water projects, which have a median cost of $2,100 per acre-foot.
  • The US House of Representatives passed the Interior and Environmental Appropriations bill for fiscal year 2017 (H.R. 5538), providing $32 billion in funding for various government and related agencies. The bill includes several California drought relief provisions, such as an increase in State Water Project deliveries and financial assistance for affected communities. The bill has been passed on to the Senate for further action.
  • The US Bureau of Reclamation has increased Class I water supply allocation for Friant Division contractors to 75%. The initial allocation announced in April was 30% and was subsequently increased three times before the current amount was settled upon. This increase was made possible by an agreement between Friant Division contractors and others to exchange water from the east side of the San Joaquin Valley.
  • An investigation by the Desert Sun showed an 8% decrease in water use by golf courses in Coachella Valley during the 12-month period between June 2015 and May 2016, compared to the same months in 2013. While imports from the Colorado River rose by 36% in that period, the overall decrease of 8% was made possible by reductions in groundwater use.
  • A new report by the Xerces Society, entitled “State of the Monarch Butterfly Overwintering Sites in California,” highlights that the population of monarch butterflies overwintering along the California coast has declined by 74% in less than two decades. Important factors influencing the decline include the loss of habitat, the widespread use of insecticides, and the increased frequency of drought.
  • The California Natural Resources Agency recently launched the Delta Smelt Resiliency Strategy, a science-based document to guide voluntary efforts by state and federal agencies engaging in the Delta Smelt conservation. The document outlines several actions, including releasing water into the Yolo Bypass to boost zooplankton production, removing invasive aquatic weeds in important smelt habitat, and increasing outflows to the Pacific Ocean in order to improve smelt habitat. The endangered fish have come close to extinction after several months of extremely dry weather.
  • Researchers at the University of California, Riverside have launched a new study to examine the impacts of the California drought on public health. The two-year project will examine the influence of drought-related water deliveries on health impacts for residents in California’s poorest regions.
  • The Department of Water Resources reported that 94% of the state’s 127 high- and medium-priority groundwater basins are fully monitored and more than 1.5 million groundwater elevation measurements from across the state have been entered into the California Statewide Groundwater Elevation Monitoring Program (CASGEM), which is managed by the DWR in partnership with local water districts. By tracking seasonal and long-term groundwater elevation trends, the program provides fundamental information to improve groundwater management in California.

California Drought Status

Drought Monitor

Drought conditions have remained unchanged over the past two weeks. Severe-to-exceptional drought spans 43% of the state, while areas under moderate-to-severe drought represent 41% of the state.

Any changes to California’s drought conditions are highly unlikely as the region is normally warm and dry during the summer months. However, the short-term outlook suggests a high chance of above normal temperatures in the coming week.


Cumulative precipitation since the beginning of the water year (Oct 1) in the San Joaquin, Northern Sierra, and Tulare Lake Basin are the same as two weeks ago, at near average (40 inches), above average (57.8 inches), and below average (25.7 inches), respectively.

Reservoir Conditions

Over the past two weeks, water levels in California’s major reservoirs (representing 27.3 million acre-feet of storage) slightly fell from 60% to 58% of statewide capacity. This storage level of 15 million acre-feet represents 82% of reported average for July 22. Lake Oroville, Shasta Lake, and Folsom Lake are now at 94%, 109%, and 77% of historical average, respectively. Water levels in the New Melones Reservoir, another major reservoir with a 2.4 million acre-feet capacity, declined slightly over the past two weeks to 40% of historical average.


Since the beginning of 2016, a total of 3,801 incidents of wildfire have burned about 123,011 acres across the state. Wildfires in Southern California average 44 acres per fire, 2.4 times larger on average than those in Northern California.

[Note: these was an error in an earlier report (July 8, 2016) by the National Interagency Fire Center, which showed that year-to-date wildfires had affected about 180,000 acres across California.]


Hydroelectric power generation in April 2016 was about 2,760,000 MWh, nearly tripling last year’s April production of 970,000 MWh. The current level is the highest for an April hydroelectric power generation since 2011, but it is still 13% less than the 2001-2011 average for April.

Groundwater Conditions

The most recent data on groundwater conditions are based on measurements taken in spring 2016. Maps of spring and fall groundwater level changes can be found here. Parts of the Tulare Lake, the South Coast, and the Colorado River hydrologic regions have experienced groundwater declines of more than 100 feet.


Read past updates here.

Additional Resources