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>>22346932, >>22346860, >>22346881 Newscum water plans to combat climate change
California Water 101
The Sacramento River is the largest river in California.
California has been called the most hydrologically altered landmass on the planet, and it is true. Today the state bears little resemblance to its former self. Where deserts and grasslands once prevailed, now reservoirs store water to move it to the arid land. Swampy marshes have given way to landfill for urban development. Wetlands have been converted to farmland. California’s water resources now support 35 million people and irrigate more than 5.68 million acres of farmland.
As a result of the development of the state’s natural resources, especially water, California has emerged as a leading agricultural producer, a major manufacturing center, the most populated state in the country and the eighth largest economy in the world.
However, this intensive development has not been without its consequences. Fish populations have been depleted. Wetlands have been drained. Dams and levees have altered natural water flow patterns. Invasive plants and species are changing ecosystems and altering native habitat. Species of many native plants and wildlife have declined or become extinct, and water quality has been impaired by agriculture, ranching, mining and urban sources.
Much of California has a “Mediterranean” climate, characterized by warm, dry summers and mild winters. Most of the precipitation falls in the winter as rain and snow. Although the climate is variable, the state receives about 200 million acre-feet of precipitation per year on average. An acre-foot of water equals about 326,000 gallons, or enough water to cover an acre of land (the size of a football field) 1 foot deep. One acre-foot is enough water to meet the annual indoor and outdoor needs of two households.
About 60 percent of all precipitation evaporates or is transpired by trees and vegetation. What’s left is roughly 75 million acre-feet per average year that flows into waterways and groundwater aquifers and ultimately becomes available to use in homes, as irrigation for farmland, by industry and in the environment.
There’s a catch. While parts of Northern California receive 100 inches or more of precipitation per year, the state’s southern, drier areas receive less precipitation – and just a few inches of rain annually in the desert regions. That means 75 percent of California’s available water is in the northern third of the state (north of Sacramento), while 80 percent of the urban and agricultural water demands are in the southern two-thirds of the state.
Despite the geographic and hydrologic challenges, California has more irrigated acreage than any other state, thanks to massive water projects that include dams, reservoirs, aqueducts and canals to deliver water to users, especially in the central and southern portions of the state. Water also is moved east to west such as through San Francisco’s Hetch Hetchy system.
Water Projects and the California Economy
California’s Water Supply
New Groundwater Rules
California’s Vast Infrastructure – The State Water Project and Central Valley Project
Where does your water come from?
The Importance of Agriculture
The Water and Energy Connection
The Delta: The Hub and Critical Link of California’s Water System
A Question of Balance and Sustainability