SAN BRUNO (CBS SF) — A major water pipeline that broke in San Bruno on Monday night, causing the loss of “millions of gallons” of water, remains open morning while regional water utilities scramble to make backup water supply plans, according to the San Francisco Public Utilities Commission.

The break in the 54-inch regional transmission line at Junipero Serra County Park in San Bruno was reported at 9:30 p.m. on Monday at the entry to the park on Crystal Springs Road, SFPUC spokesman Tyrone Jue said.

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The pipeline, known as San Andreas Pipeline No. 2, is part of the Hetch Hetchy Water System and serves three Peninsula water agencies, according to the SFPUC.

Those agencies are working today to establish backup water supply plans. In the meantime, water is still flowing in the pipeline to allow those utilities to maintain sufficient water pressure for firefighting and water distribution, SFPUC officials said.

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Once the backup plans are in place, SFPUC work crews will isolate the pipeline and conduct repairs. Jue estimated the amount of water lost was “easily millions of  gallons” and said there is no estimated time yet for when repairs will be completed.

The water is flowing back through the park and into a creek that runs into the Bay, so no property damage has been reported, Jue said. Junipero Serra County Park is closed and will remain so until further notice, according to the SFPUC.

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