Drought — Carquinez Strait and Delta, California

2021-10-08 to 2021-10-31 · Carquinez Strait and Delta, California

Event narrative

For the month of October, the U.S. Drought Monitor kept all of zone 18 in exceptional drought (D4). The zone continued to see much of the same impacts already effecting the region. They continue to mention impacts to: agriculture, water supplies, recreation, and ecosystems. Farmers north and south of the Sacramento-San Joaquin River Delta will continue to receive no water from the Central Valley Project. All of zone 18 is in the official drought emergency proclamation. The Delta cross channel gates remain closed. Concern was noted that nearly all endangered winter-run Chinook salmon could perish this fall. Drought has also reduced California's almond harvest by 13%. Farmers planted about 100,000 fewer acres of rice in the Sacramento Valley, leading to less food and increased potential for disease for birds migrating through the Pacific Flyway. Ranchers are seeing 10-25% reduction in herds due to feed shortages. Effective on August 19, the State Water Resources Control Board released an 'emergency curtailment' order that would deprive thousands of farmers of the use of rivers and streams in the Sacramento-San Joaquin Delta watershed.

Wider weather episode

Northern California typically experiences a wet season, October through May, and a dry season May through September. Last year's water year, October 2019 through September 2020, was one of the driest on records. This likely contributed to the U.S. Drought Monitor's decision to place portions of interior northern California into extreme drought on September 29, 2020. Portions of Shasta, Tehama, Butte, Glenn, Colusa, Yolo, Solano, Yuba, Nevada, and Sacramento counties remain in extreme drought. The rest of interior northern California was placed into severe drought (D2) on December 8; however, the state of California has not announced that these locations are in drought. On 4/21/2021 the Biden-Harris administration announced the formation of an Interagency Working Group to address worsening drought conditions in the West. On 5/10/2021 Governor Gavin Newsom significantly expanded his April 21 drought emergency proclamation to include Klamath River, Sacramento-San Joaquin Delta and Tulare Lake Watershed counties where accelerated action is needed to protect public health, safety and the environment. In total, 41 counties are now under a drought state of emergency, representing 30 percent of the state's population. By late June more wildlife was observed in urban interfaces than normal, notably bears and rattlesnakes, in search of wetter, cooler conditions. Widespread water theft has also been reported. On July 8th, the Governor of California asked for all Californian's including businesses, to voluntarily reduce water usage by 15%. On August 10th DWR reported the drought has led to a 123% increase in the number of acres burned this year, compared to 2020. DWR also reported that the low reservoir water levels have also affected energy supplies, agriculture, communities and state recreation parks.

Source: NOAA Storm Events Database, event_id 990738. Narrative written by the NWS forecast office that issued the report.