Bulletin No. 4, Water Resources of California, A Report to the Legislature of 1923
Keywords:infrastructure, irrigation, planning and management, water supply
Agricultural Land Stewardship (Resource Management Strategy)$0.00 Add to Downloads
Agricultural Land Stewardship (Resource Management Strategy)California Department of Water Resources (DWR) | July 29, 2016...Summary
This resource management strategy focuses primarily on private land in agriculture including cultivated land and rangeland. Agricultural land in California comprises about 31.6...
This resource management strategy focuses primarily on private land in agriculture including cultivated land and rangeland. Agricultural land in California comprises about 31.6 million acres (California Department of Conservation, Division of Land Resource Protection, Farmland Mapping and Monitoring Program 2008). About 12.4 million of these acres are cultivated, while the remaining 19.2 million acres are rangeland (California Department of Forestry and Fire Protection 2010).
Agricultural systems in California are varied in the way resources are used, ranging from intensive conventional agriculture (irrigated crop cultivation) to more extensive systems such as livestock grazing, each with a different relationship to natural resources. They also affect and are affected by surface hydrology and groundwater recharge in different ways. Stewardship of this land requires constant balancing among natural constraints, market forces, and ever-changing social expectations. Institutions and policies have been developed in response to these challenges. Public investment in water infrastructure (reservoirs, canals, drains, levees, dykes) has been in the forefront of these.
This resource management strategy report focuses on agricultural land stewardship (ALS) strategies that can be incorporated into relevant adaptive management of agricultural land at different levels, including landscape, regional and project.
California Water Plan 2013: Sacramento River Hydrologic Region Report$0.00 Add to Downloads
California Water Plan 2013: Sacramento River Hydrologic Region ReportCalifornia Department of Water Resources (DWR) | October 30, 2014...Summary
The Sacramento River Hydrologic Region (see Figure SR-1 includes the entire California drainage area of the Sacramento River (the state’s largest river) and...
The Sacramento River Hydrologic Region (see Figure SR-1 includes the entire California drainage area of the Sacramento River (the state’s largest river) and its tributaries. The region extends from Chipps Island in Solano County north to Goose Lake in Modoc County. It is bounded by the Sierra Nevada on the east, the Coast Ranges on the west, the Cascade and Trinity mountains on the north, and the Sacramento-San Joaquin River Delta (Delta) on the south. The Sacramento River Basin actually begins in Oregon, north of Goose Lake, a near-sink that intercepts the Pit River drainage at the California-Oregon border.
Some key issues for this region are summarized here and discussed further later in this report.
Agriculture. Between 2005 and 2010, the region supported about 1.95 million acres of irrigated agriculture on average. Approximately 1.58 million acres is irrigated on the valley floor. The surrounding mountain valleys add about 370,000 irrigated acres to the region’s total — primarily as pasture and alfalfa. The gross value of agricultural production in the Sacramento Valley for 2011 was about $4.1 billion (California Department of Food and Agriculture 2013). Rice and walnuts are the highest grossing crops in the region followed by almonds and tomatoes. The direct, indirect, and induced effects of the agricultural industry to the regional economy are discussed in this report.
Groundwater. With a 2005-2010 average annual extraction volume of 2.7 million acre-feet (maf), groundwater pumping in the Sacramento River Hydrologic Region accounts for 17 percent of all the groundwater extraction in California — the third highest among the 10 hydrologic regions in California, behind Tulare Lake Hydrologic Region with 38 percent and San Joaquin River Hydrologic Region with 19 percent of the total. Overall, groundwater contributes to about 31 percent of the total water supply. Most groundwater extraction in the region occurs for agricultural water use (2.4 maf), meeting about one-third of agricultural water demands. Groundwater extraction for urban water use is significantly less (465 thousand acre-feet [taf]), which meets about half of the urban water needs. Groundwater levels for much of the region have declined from 2005 to 2010. Groundwater level declines ranging from 20 to 30 feet are seen in the northwestern portion of the Sacramento Valley Groundwater Basin. Declines ranging from to 10 to 20 feet are seen in the northern, the mid- to south-western, and the southeastern portions of the valley. For the rest of the Sacramento Valley Groundwater Basin and the Redding Area Groundwater Basin, groundwater level declines have
ranged from zero to 10 feet.
Flood. Exposure to a 500-year flood event in the region threatens approximately one in three residents, almost $65 billion in assets (crops, buildings, and public infrastructure), 1.2 million acres of agricultural land, and over 340 sensitive species. Almost 95 percent of Sutter County residents, more than 55 percent of Yuba County and Yolo County residents, and more than 50 percent of agricultural land region-wide are exposed to the 500-year flood event.
Climate Change. Several different climate regions overlie portions of the Sacramento River Hydrologic Region. Air temperature data collected for the past century has been summarized by the Western Regional Climate Center (WRCC) for the different regions which are outlined below.
- Within the WRCC North Central climate region, mean temperatures have increased by about 0.8 to 1.7 °F (0.4 to 0.9 °C) in the past century, with minimum and maximum temperatures increasing by about 1.2 to 2.1 °F (0.7 to 1.2 °C) and 0.1 to 1.5 °F (0.1 to 0.8 °C), respectively.
- Within the WRCC North East climate region, mean temperatures have increased by about 0.8 to 2.0 °F (0.5 to 1.1 °C) in the past century, with minimum and maximum temperatures increasing by about 0.9 to 2.2 °F (0.5 to 1.2 °C) and by 0.5 to 2.1 °F (0.3 to 1.2 °C), respectively.
- Within the WRCC Sierra climate region, mean temperatures have increased by about 0.8 to 2.0 °F (0.5 to 1.1 °C) in the past century, with minimum and maximum temperatures increasing and decreasing by about 1.7 to 2.8 °F (0.9 to 1.5 °C) and by -0.2 to 1.3 °F (-0.1 to 0.7 °C), respectively.
- Within the WRCC Sacramento-Delta climate region, mean temperatures have increased by about 1.5 to 2.4 °F (0.9 to 1.3 °C) in the past century, with minimum and maximum temperatures increasing by about 2.1 to 3.1 °F (1.2 to 1.7 °C) and by 0.8 to 2.0 °F (0.4 to 1.1 °C), respectively (Western
Regional Climate Center 2013).
The region also is currently experiencing impacts from climate change through changes in statewide precipitation and surface runoff volumes, which in turn affect availability of local and imported water supplies. During the last century, the average early snowpack in the Sierra Nevada decreased by about 10 percent, which equates to a loss of 1.5 maf of snowpack storage (California Department of Water Resources 2008). Projections and impacts based on modeling of climate change are included in this report.
Impacts of California’s Ongoing Drought: Agriculture$0.00 Add to Downloads
Impacts of California’s Ongoing Drought: AgriculturePacific Institute | August 26, 2015...Summary
California’s agriculture sector has exceeded expectations during the most severe drought in recorded history at the cost of massive but unsustainable groundwater pumping....
California’s agriculture sector has exceeded expectations during the most severe drought in recorded history at the cost of massive but unsustainable groundwater pumping. Continued groundwater overdraft, while reducing the economic impacts of the drought for the agricultural sector now, has shifted the burden to others, including current and future generations forced to dig deeper wells, find alternative drinking water sources, and repair infrastructure damaged by subsidence. That is the conclusion of the new study, Impacts of California’s Ongoing Drought: Agriculture, released today by the Pacific Institute, an independent global water think tank.
This new study is the first comprehensive analysis of the actual impacts of the drought on California agricultural revenue and employment through 2014 – the last year for which data are available. The study, drawing on data from the USDA National Agricultural Statistics Survey and the California Employment Development Department, analyzes acreage, revenue, and employment figures from 2000-2014. Production costs, impacts on animal or nursery products, or regional impacts are not examined because these data are not yet available. The study’s results provide critical insight into how the state can maintain a healthy agriculture sector in a future likely to see less water, more extreme weather, and greater uncertainty.
California remains the largest agricultural producer in the U.S. in total output and in exports. During the drought, California’s agriculture sector has experienced record-high crop revenue and employment. Last year farmers harvested 640,000 fewer acres, which was 9 percent below pre-drought levels, yet crop revenue remained strong. Indeed, crop revenue peaked in 2013 at $34 billion – the highest level in California history. In 2014, crop revenue declined by $480 million, representing a 1.4 percent reduction from 2013 levels. All economic estimates have been corrected for inflation. Statewide agriculture-related jobs also reached a record-high of 417,000 people in 2014, highlighting the sector’s ability to withstand the reduction of available water.
Oil, Food, and Water: Challenges and Opportunities for California Agriculture$0.00 Add to Downloads
Oil, Food, and Water: Challenges and Opportunities for California AgriculturePacific Institute | December 1, 2015...Summary
A new comprehensive study by the Pacific Institute sheds light on the risks posed when oil and gas exploration and production operate alongside...
A new comprehensive study by the Pacific Institute sheds light on the risks posed when oil and gas exploration and production operate alongside agriculture.
“There is growing concern about competition for land and water, and the impacts of soil and water contamination on the food supply and health and safety of farmworkers and consumers,” said Matthew Heberger, the study’s lead author.
The disposal of oil and gas wastewater, which contains harmful chemicals, is a particular concern for agriculture. Disposal in unlined percolation pits poses a significant risk of contaminating groundwater resources that may, in turn, be used by agriculture. While this practice has been banned in several states, it is still widely used in California’s Central Valley, one of the nation’s most important agricultural regions. There are also serious deficiencies in the way California regulates the underground injection of wastes – current practices are not sufficiently protective of freshwater aquifers that may be used as drinking water or to irrigate crops and water livestock.