CITY PUSHES WATER-SAVING TOILETS WITH $100 REBATES

Santa Monica is offering residents $100 rebates to switch to low-flow toilets, which start at $95 but can run up to $500 for luxury models. If the $3 million program reaches its target of retrofitting 25 percent of bathrooms in the city, 1 million gallons of water will be saved every day, says Atossa Soltani, conservation coordinator for the city of 100,000. Taxpayers won't have to spend $5 million to $7 million on new sewage treatment capacity. They can also forego buying 935 acre/feet of water per year from the Metropolitan Water District of Southern California - and that state agency is putting up cash to help.

It is MWD's responsibility to see that the hot tubs and lawn sprinklers of 15 million people - half the state's population - never run dry. But neither of the agency's two water sources meets original expectations. A 1963 United States Supreme Court decision cut California's flow from the Colorado River aquaduct in half, to 550,000 acre/feet per year. And MWD only gets 1 million acre/feet per year from northern California, half what it expected.

Although the state is in its fourth consecutive year of drought, MWD is coping with current needs, says spokesman Bob Gomperz. But with annual population increases of 300,000 in its service area, the agency expects demand 20 years from now to outstrip supply by a thirsty 40 percent.

That projection, Mr. Gomperz says, means that California needs conservation programs like Santa Monica's.

As for giving the replaced units a burial at sea, Ms. Soltani says California's Department of Fish and Game has ``never built a toilet reef before.'' But it has built reefs from cars, tires, and quarry stones, so she expects the department to accept the proposal. Soltani adds that Santa Monica is already ``telling people to give us their old toilets.''