Effort to save water underway

The Bay Area population is expected to grow in the next 25 years and aggressive conservation efforts already used in many cities will help curb water demand from the Hetch Hetchy reservoir, according to landmark report released yesterday by the San Francisco Public Utilities Commission.

The report shows that the cities and agencies across the Peninsula will continue to lower the demand by implementing new plumbing codes and conservation measures, but will remain heavily reliant on the aging Hetch Hetchy water supply.

The report was compiled over two years using data compiled from Peninsula cities served by Hetch Hetchy. It provides officials with a better understanding of what conservation efforts will work best for the changing population in the next 30 years, said Art Jensen, general manager of the Bay Area Water Supply and Conservation Agency.

"It's the most rigorous approach that has been taken so far," Jensen said.

By implementing water recycling programs and new plumbing codes that require efficient pipes and faucets, cities will continue a decline in water demand that started during the 1987 drought. Total water demand is expected to grow by 14 percent compared to a projected population growth of 17 percent, bringing the demand for water from 366 million gallons a day in 2001 to a projected 417 million in 2030.

However, the report states there is still a chance to save 24 million gallons per day by increasing conservation efforts.

Companies can install toilets with heavy and light flush options and half gallon flush urinals. The report also recommends that buildings with multiple units install sub meters. Making each unit responsible for its own water usage usually leads to conservation.

Despite efforts to diversify water supplies on the Peninsula, San Francisco will continue to rely on the Hetch Hetchy water system for more than 90 percent of its water supply while regional customers will continue to rely on Hetch Hetchy water for nearly 66 percent of its supply.

The Hetch Hetchy water system spans more than 160 miles from O'Shaughnessy Dam in Yosemite National Park through much of the Bay Area to San Francisco. Built more than 70 years ago, the system serves more than 2.4 million Bay Area residents, generates clean hydropower for San Francisco and provides irrigation water to the Modesto and Turlock. In 2002, San Francisco voters and Bay Area ratepayers approved $3.6 billion to rebuild and improve the reliability of the entire system, which is highly vulnerable to major earthquakes or other emergencies that could disrupt the region's water supply for months.