Wednesday, June 9, 2021

Water Restrictions Spread in California

In May Governor Gavin Newsom expanded his April 21 drought emergency proclamation to include 41 counties under a drought state of emergency, representing 30 % of the state’s population. On Wednesday Santa Clara County voted to declare a water supply emergency and institute mandatory water use restrictions. California’s wet season is almost finished, and the first six months of the water year rank as the fourth driest on record.

From Drought Monitor

Warm temperatures and extremely dry soils attributed to climate change have further depleted the Sierra-Cascade snowpack, and resulted in historic and unanticipated (at least by California) reductions in the amount of water flowing to their major reservoirs, especially in Klamath River, Sacramento-San Joaquin Delta and Tulare Lake Watershed counties.

“With the reality of climate change abundantly clear in California, we’re taking urgent action to address acute water supply shortfalls in northern and central California while also building our water resilience to safeguard communities in the decades ahead,” said Governor Newsom. “We’re working with local officials and other partners to protect public health and safety and the environment, and call on all Californians to help meet this challenge by stepping up their efforts to save water.”

In April, Governor Newsom declared a State of Emergency in Mendocino and Sonoma counties due to severe drought conditions in the Russian River Watershed. In May the Governor expanded the state of emergency to address acute drought impacts to the following 39 counties: Del Norte, Humboldt, Siskiyou, Trinity, Alameda, Alpine, Amador, Butte, Calaveras, Colusa, Contra Costa, El Dorado, Fresno, Glenn, Kern, Kings, Lake, Lassen, Madera, Mariposa, Merced, Modoc, Napa, Nevada, Placer, Plumas, Sacramento, San Benito, San Joaquin, Shasta, Sierra, Solano, Stanislaus, Sutter, Tehama, Tulare, Tuolumne, Yolo and Yuba counties adding them to Mendocino and Sonoma counties.

Extraordinarily warm temperatures in April and early May separate this critically dry year from all others in the California record. California experienced an accelerated rate of snow melt in the Sacramento, Feather and American River watersheds, which normally feed the major reservoirs of the state and federal water projects. This year, however;  the small snowpack was sitting on very dry ground and seeped into the earth rather than flowing into their rivers and streams that feed the reservoirs.

Warming temperatures and lack of rain also prompted water diverters below the dams to withdraw their by right water much earlier and in greater volumes than typical even in other recent critically dry years. These factors reduced expected water supplies by more than 500,000 acre feet, enough to supply up to one million households with water for a year. Thfe drastic reduction in water supplies means these reservoirs are extremely low in the counties the drought proclamation covers.

The Governor’s proclamation directs the State Water Board to consider modifying requirements for reservoir releases and diversion limitations to conserve water upstream for later in the year to maintain water supply, improve water quality and protect cold water pools for salmon and steelhead. The state of emergency also directs state water officials to expedite the review and processing of voluntary transfers of water from one water right holder to another, enabling available water to flow where it is needed most.

The Governor has directed state agencies to partner with local water suppliers to promote conservation through the Save Our Water campaign, a critical resources for Californians during the 2012-2016 drought. Some municipalities have already adopted mandatory local water-saving requirements, and many more have called for voluntary water use reductions.

“It’s time for Californians to pull together once again to save water,” said California Natural Resources Agency Secretary Wade Crowfoot. “All of us need to find every opportunity to save water where we can: limit outdoor watering, take shorter showers, turn off the water while brushing your teeth or washing dishes. Homeowners, municipalities, and water diverters can help by addressing leaks and other types of water loss, which can account for over 30 percent of water use in some areas.”

However, even herculean action on the part of suburban and urban residents is not going to salvage the situation for long. According to the Fourth National Climate Assessment Volume I and II the impacts of global climate change are already being felt in the United States and are projected to intensify in the future. The control of global greenhouse gas emissions is not in our hands. The United States represents about 15% of global emissions. In order to avoid exceeding 1.5 degrees C of warming, the recent The Intergovernmental Panel on Climate Change (IPCC) says carbon pollution must be cut almost in half by 2030, and then reach "net zero" by mid-century. China and India carbon emissions are still growing even as our emissions have fallen.

California water problems fundamentally result from having a vibrant economy and society in an arid climate that is becoming dryer. The demand for cheap water exceeds supply. In previous years and hopefully also in the future, the Pacific storm track leave tremendous accumulations of snow in the Sierra Nevada Mountains. The Sierra Snowpack melted in the early warm weather and was absorbed into the dry earth rather than flowing into the rivers and reservoirs this year. 

California has 1,200 miles of canals and nearly 50 reservoirs. In an “average” year the system captures enough water to irrigate about four million acres and provide water to 30 million people. Without this extensive management system that moves water from the north to the south and delivers water from the Colorado and Klamath Rivers, California’s limited rainfall and diminishing groundwater reserves could not meet as much of the demand for water. California has the largest water storage and transportation system in the world, but without rain there is nothing to store. 

Californians pride themselves on being environmentally conscious and mindful of conserving natural resources. California local water agencies have invested in water recycling, conservation, groundwater storage and other strategies to stretch supplies. Nonetheless, water demand within the state has never been greater and the available water resources have decreased as our climate changes. Year-round agriculture has been made possible by water used for irrigation. California produces nearly half of the nation's fruits, nuts and vegetables. Fruit and nut trees must be watered all year they cannot lie dormant for several years during a drought. The limit to California’s agricultural bounty is water availability.

Irrigated agricultural consumes over 75% of the delivered water in California, which produces about half of U.S. grown fruits, nuts, and vegetables. Californians have stretched their annual rainfall about as far as it could go; yes there are still some inefficiencies in the systems, but it is the new climate normal tell us that precipitation in California has decreased. While population has increased. 

To change the fundamental water equation in the state the Pacific Institute recommends that of 1.3 million acres of impaired lands in the Central Valley be removed from irrigation and agricultural use. Though this land represents less than 5% of the agricultural land in California it would save 3.9 million acre-feet of water per year,  9% of the water used in California and is equal to two thirds of the total water used for urban residential use. 

Meanwhile, drought is not their only problem. Wildfire season has already begun with portions of California currently under a Red Flag Warning. Fire season in California and across the West is starting earlier and ending later each year. Climate change is considered a key driver of this trend. Warmer spring and summer temperatures, reduced snowpack, and earlier spring snowmelt create longer and more intense dry seasons that increase moisture stress on vegetation and make forests more susceptible to severe wildfire. The length of fire season is estimated to have increased by 75 days across the Sierras and seems to correspond with an increase in the extent of forest fires across the state. 

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