5.1: Introduction
California will always be inextricably linked to its water resources. Water continues to shape the state’s development and no resource is as vital to California’s urban centers, farms, industry, recreation, scenic beauty, and environmental preservation. As of 2023, California's interconnected water system serves over 39 million people and irrigates over 5,680,000 acres of farmland. As the world's largest, most productive, and potentially most controversial water system, it manages over 40 million acre-feet (49 km 3 ) of water per year.
Water and water rights are among the state's divisive political issues. Due to the lack of reliable dry season rainfall, water is limited in the most populous U.S. state. Among all the effects of climate change, changes in precipitation will be the hardest to predict. Studies conducted by the California Natural Resources Agency suggest that there will be more dry days and years in the future with occasional downpours. It is also estimated that the southern and inland regions of the state that are already dry to become more arid over time while the northern part of the state that currently receives much of the state's rainfall will continue to get wetter with the onset of climate change. Additionally, the intense drawdown of groundwater to support the growing urban expansion also impacts the deep roots of trees, and lowering the overall water table.
An ongoing debate is whether the state should increase the redistribution of water to its large agricultural and urban sectors or increase conservation and preserve the natural ecosystems of the water sources. Other conversations involve the building of large home developments in impacted areas, such as the 21,000-home development behind Six Flags Magic Mountain in the city of Santa Clarita that began construction in late 2020.