Tuolumne River threatened by inflated water demand

Based on inflated projections of water needs, San Francisco wants to divert an additional 25 million gallons per day from the federally designated wild-and-scenic Tuolumne River, below Hetch Hetchy Valley in Yosemite National Park.

The San Francisco Public Utilities Commission claims that its Bay Area water-agency customers will demand 19% more water in 2030 than today. This estimate would shape new long-term water-sales contracts between the PUC and 28 water agencies in Alameda, San Mateo, and Santa Clara Counties.

A recent analysis, however, by the Pacific Institute for Studies in Development, Environment, and Security, an independent nonprofit research organization world-renowned for its expertise on water conservation and water-use efficiency, differs. It concludes that demand should be much lower.

The Pacific Institute analysis points out that the PUC projections ignore the impact of increasing water rates - set to quadruple over the next 12 years! - on water use. These rates will decrease consumption, particularly for non-residential and outdoor uses. The PUC also makes the unlikely assumption of no changes in the current composition of commercial and industrial businesses and ignores variability in quantity and purpose of water use among non-residential users. Both of these errors can lead to potentially large inaccuracies when forecasting demand. The water-demand projections are also based on dated forecasts of employment. Bay Area economic recovery has proven slower than expected, reducing the job outlook and therefore water demand.

Conservation

Another key factor for water needs is conservation.

The PUC projects that its combined conservation programs for wholesale and retail customers will reduce water demand in 2030 by only 4%. It forecasts a slight increase in per-capita demand for its water-agency customers between now and 2030.

Other cities do much better. For example, the Seattle regional water system reduced per-capita demand by 30% between 1975 and 2005, and it is currently committed to reducing water use by an additional 1% annually. Likewise, the Metropolitan Water District of Southern California decreased water use by 16% from 1990 to 2003, despite a 14% increase in population.

Practical and proven water-conservation technologies exist. San Francisco and its water-agency customers need to strengthen their commitment to reducing water use through conservation.

The Pacific Institute's analysis tells us that the PUC's plan to divert an additional 25 million gallons per day from the Tuolumne River is not supported by sound science. It is time for the PUC and its water-agency customers to forecast water usage more accurately and to pursue a sustainable water plan - capping water sales at current levels. With increased conservation and recycling, we can stretch our water supply without imperiling the Tuolumne River.

WhatYouCanDo

Write to Ryan L. Brooks, president of the San Francisco Public Utilities Commission, and (Hayward residents especially) to Hayward Mayor Michael Sweeney, each at:

c/o Sierra Club Bay Chapter
2530 San Pablo Ave.
Berkeley, CA 94702.

Urge them to meet our water needs and protect the Tuolumne River for future generations through conservation and recycling rather than by withdrawing more water and depleting the Tuolumne. We have enclosed a post card to one of these officials in many copies of this Yodeler; please send that in, but your hand-written letters are even more effective.

To review the full Pacific Institute report, as well as updates about the PUC's environmental-review process, see the Tuolumne River Trust web site.

Heather Dempsey, Bay Area program director, Tuolumne River Trust