Many Los Angeles residents may have to change the days they water their lawns under a proposal approved Tuesday by the Los Angeles Department of Water and Power’s (DWP) Board of Commissioners.

A water main break on Fairfax Avenue last September was one of many that occurred after water rationing was implemented. (photo by Edwin Folven)

The plan is designed to reduce pressure fluctuation in water mains, and came as a result of the numerous pipe ruptures that occurred since July last year. The plan would alter current water rationing restrictions, where residents are only allowed to water their lawns on Mondays and Thursdays for 15 minutes. Residents with odd-numbed addresses would continue to water on the current schedule, while residents with even-numbered addresses would only be allowed to water on Tuesdays and Fridays.

An independent review conducted by scientists and experts from the Jet Propulsion Laboratory, the University of Southern California and Caltech, among others, determined the pipe breaks were the result of fluctuations in pressure caused by the water-rationing program. An internal DWP investigation concluded that the ruptures resulted from fluctuations in pressure caused by major water pipes known as “trunk lines” being shut off to accommodate repairs to portions of the water system. While the DWP board has not officially said which theory is correct, members agreed that changes needed to be made to prevent water pressure fluctuation in the future, according to Stephanie Interiano, a spokesperson for the DWP. The new rationing plan will be subject to approval by the Los Angeles City Council, and a date to review the proposal has not yet been scheduled.