BEVERLY HILLS (CBSLA) — Sunset Boulevard remained mostly closed Tuesday as crews continue to work on fixing a water line leak that has all of Beverly Hills conserving water for at least the rest of the week.

A leak was detected Friday in a 32-inch cast iron pipe installed in the 1940s, and grew into a full-blown water main break by Sunday, when all of eastbound Sunset at Alpine Drive was shut down. One westbound lane on Sunset remains open.

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The leak was in the Metropolitan Water District’s Santa Monica Feeder, and repairs required the complete shutdown of the line, officials said. Having that line out of commission leaves Beverly Hills without its primary source of water, prompting the city to urge residents to reduce their water use while the water main is being repaired.

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“We need the help of our residents. We’re asking them to avoid watering their lawns and gardens, take shorter showers, avoid unnecessary loads of laundry and do whatever they can to keep their water use down,” Beverly Hills Mayor Julian A. Gold said. “We know it’s the holidays and it’s a sacrifice, but we also know our residents are willing to pitch in and help when needed.”

Beverly Hills is now relying on local reservoirs for water until the line is fixed.

The cause of the leak is still under investigation.

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(© Copyright 2018 CBS Broadcasting Inc. All Rights Reserved. City News Service contributed to this report.)