Smarter Forest Management Could Yield Water for California’s Population Growth

There is mounting evidence that poor policies are creating California’s water troubles. California has a policy problem disguised as a water problem. The poor policies create massive misallocation of water and water waste throughout the state.

More evidence of this comes from Roger Bales, a hydrologist with the University of California, Merced, and Scott Stephens, a professor of fire science at the University of California, Berkeley. Professor Bales argues that the Sierra Nevada, which is the source of 60 percent of California’s water in a typical year, has twice the number of trees than 100 years ago. Deliberate government policies to limit timber harvesting and suppress naturally caused forest fires have produced overgrowth.

All of these additional trees over millions of acres consume snowpack runoff that in the past would have emptied into California’s streams, rivers, reservoirs, and canals for use throughout California.

The solutions are to allow more naturally caused low-intensity fires to burn and allow timber companies to harvest small trees, especially thirsty pines, to thin the forest. But government policy has generally prevented either solution, often because of opposition by environmental groups. Once again, good intentions have resulted in harmful unintended consequences, this time less water for people and more high-severity forest fires when fires occur.

Thinning the Sierra could provide up to one million acre-feet of water annually, according to Professor Bales—qqqenough water for the yearly needs of two million California households. Incidentally, the San Francisco Bay Area is expected to add two million people by 2040.