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Parched Future? California’s Population Growth A Challenge For Water Supply — But Variety Of New Options Could Keep State Afloat

Rapid Growth in Hot Inland Regions Will Play Major Role in Escalating Demand

SAN FRANCISCO, California, July 27, 2005 — Perennial warnings about “the California water shortage” may be more compelling given a new study released by the Public Policy Institute of California (PPIC). The study finds soaring population growth in the state’s hottest regions will lead to an enormous jump in future demand.

By analyzing the state’s per capita water usage, then factoring in its projected population growth, the report comes up with some striking numbers: If the rate of urban water use continues at recent levels, California will face a 40 percent increase in demand by the year 2030. That’s because 14 million more people – the state’s predicted population increase between 2000 and 2030 – will be tapping into the water supply at an average rate of 232 gallons of water per person per day.

Where growth is occurring also weighs heavily on demand. Half of all new residents in California are expected to live in the state’s three inland valleys, where the harsher climate and larger number of single-family homes result in significantly greater water use for landscaping. Indeed, landscape irrigation accounts for over half of residential use in the inland valleys – compared to one-third or less in coastal areas. “New plumbing codes and water-efficient appliances greatly help to curb indoor water use in new homes,” says the report’s author, PPIC research fellow Ellen Hanak. “In growing regions like the Inland Empire, San Joaquin Valley, and Sacramento Metro, where the summers are long, hot, and dry, the pressure is likely to come from outdoor use.”

But despite the demographic forecast, the report finds great potential for meeting future water needs through conservation, recycling, and other sources. Keys to success are better long-term water planning and streamlining the process for screening and approving new housing development. Indeed, the analysis, Water for Growth: California’s New Frontier, finds that “show me the water” laws passed in 2001 – which require new housing developments to demonstrate sufficient long-term water supplies – are being enforced effectively and warns that simply rejecting growth could lead to housing shortages. “The challenge is to screen well without unreasonably slowing development,” says Hanak. Although the state plays an important role, planning for adequate water supply lies primarily in the hands of city and county water agencies – and is most affected by local land-use decisions.

The Public Policy Institute of California is a private, nonprofit organization dedicated to improving public policy in California through independent, objective, nonpartisan research on major economic, social, and political issues. The institute was established in 1994 with an endowment from William R. Hewlett.

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