Lane closures in a prominent Studio City intersection may be necessary through the rest of the week, as crews repair the underground water main that sprung a leak and sent water gurgling up through the roadway last Saturday evening.
It was the second time in six years that a failure in the underground municipal water delivery system caused flooding in the intersection of Ventura Boulevard and Coldwater Canyon Avenue, though this time nowhere near as severe as in 2009.
Saturday night Los Angeles Department of Water and Power crews were able to shut off the leaking line before water entered any shops or homes. Some passers-by said they had first noticed water appearing as early as last Thursday.
The failure occured at a connection point for plastic sleeves that were retrofitted 16 years ago inside the existing 30 inch steel pipe, according to DWP District Superintendent Charles Sparks, clarifying an earlier statement by a DWP spokesman that the leak occured at a "valve."
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The plastic connection should not have failed so soon, and why it did so is not yet clear, Sparks said.
Repairing it will require ordering parts and scheduling a subcontrator. Sparks said the work will be routed to a location thirteen feet north of the current excavation to avoid other existing utility lines. It could also ease the intrusion of work on Ventura Boulevard.
In recent decades, DWP has begun dealing with aging infrastructure that in some cases dates back a century to the era of William Mulholland, and is now beyond its intended service span.
Plastic retrofitting offers the advantanges of lower expense and avoiding the need for trenching in roadways.
The 20-inch-diameter plastic sleeve is large enough to be considered a "trunk line," but far smaller than the 64 inch line that in 2009 failed beneath Coldwater a few hundred feet south of Ventura Blvd. That cast iron pipe dated to 1914 and evidenced extensive corrosion. The rupture released thousands of gallons of water a minute and caused extensive flooding in shops on Ventura Boulevard and homes in the residential neighborhood south of the boulevard.
The overdue replacement of the trunkline to Mulholland Drive affected traffic on Coldwater Canyon for three and a half years.
"This was messed up for the longest time," recalled Jay Frailich, whose daily walk with his wife takes him past the latest gaping hole dug by DWP repair crews.
The 2009 flood triggered renewed focus on DWP's need to upgrade its infrastructure.
Pressure to speed repair and replacement older pipes was further charged by last summer's catastrophic failure of a trunkline junction beneath Sunset Boulevard, sending water flooding into the UCLA campus. Outrage over the loss of the water was amplified by California's worsening drought and imposition of water conservation measures on water users.
Earlier this year, DWP began developing a rate increase proposal, in part to fund infrastructure improvement.
The details have yet to be finalized, but DWP projects it would add several dollars a month to the bills of most residential customers.
"I'd rather pay the extra bucks and save myself some detours," said Studio City resident Sydney Esensten.
But the Saturday leak demonstrated it is not only older pipelines that can fail.