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Meet LA County's ‘Storm Boss' who controls rainwater during El Nino





<b>January 9, 2016</b> - A paean to the heroic people at LA County Flood Control who agonize over which element to stress: flood protection or water capture.


Steve Scauzillo


Pasadena Star-News


Water is now flowing down the San Gabriel River near the Mountain Cove Community after the recent El Nino storms in Azusa on Friday. Watchara Phomicinda/Staff Photographer

There’s a guy who is called the Storm Boss who oversees the county’s dams and reservoirs. At the first sign of green or red Doppler blotches on a radar screen, or charcoal-gray clouds circling overhead, he decides how much water to keep and how much to release.

Keeping it means saving supplies for those hot days in summer or for the next drought. Releasing it down river means two things: 1) Much gets lost to the ocean and 2) Some of it pools at spreading grounds, percolating down into local aquifers.

Therein lies the Storm Boss’s inherent paradox: Is his job to prevent flooding? Or to capture storm water?

The answer is both.

“Releasing. Holding. Releasing. Holding. It is an intricate process,” was how Mark Pestrella, chief deputy director of the Los Angeles County Department of Public Works, described on Friday the Storm Boss’s duty.

After nearly a week of El Niño storms that dumped 2.5 to 4 inches of rain in the coast and valleys and up to 7 inches in the foothills and mountains, the county has reported no significant flooding, he said. Everything is working as it should.

So, when people say: Why is all that water wasted to the ocean? They are half wrong. But also, half right. Let me explain.

The Los Angeles Basin is a giant flood plain. Before the Army Corps of Engineers channelized the L.A. River, the Arroyo Seco, the San Gabriel River (portion from Duarte to Long Beach) and the Santa Ana River, water and debris out of the great San Gabriel and Santa Monica mountains spread like jam on toast throughout the flatlands. That stuff is called alluvial fan.

JPL climatologist and El Niño expert Bill Patzert likes to say the LACDPW and L.A. County Flood Control District designed a system that performs as it’s supposed to do. The storm water reached the ocean, instead of your Aunt Sylvia’s front room. Mission accomplished.

Now, people want to undo that design? That is a difficult row to hoe, to say the least. And another story.

Nonetheless, Pestrella’s people are heightened to the flip side. Who wouldn’t be after four years of drought, dropping reservoir levels and shrinking ground-water basins?

During the past week, the department captured 9,700 acre feet of storm water, or about 3.2 billion gallons. That’s enough to serve 77,600 residents in a year, said Bob Spencer, LACDPW spokesman. Over a non-drought year, the county will capture 200,000 acre-feet, Pestrella said.

“Our reservoirs and spreading grounds have been active (during the storms). They are operating at full capacity and are capturing the maximum amount we can capture through these events,” Pestrella added.

He concedes the amount captured is small but called it a down payment that could lead to tearing up the deed to the drought. That of course, may take years.

Three key dams hold back water in the San Gabriels. Rainfall totals at Morris Dam, just north of Azusa, reached 5.96 inches from Tuesday to Thursday evening. Cogswell Dam, above the West Fork of the San Gabriel River, experienced the highest rainfall total anywhere in the county: 7.24 inches. Eaton Wash Dam in east Pasadena (near a spreading ground) took in 5.28 inches.

“Morris Dam is filling up. It can hold 50,000 acre feet,” he said. The nearly 100-year-old structure received a $10 million makeover in July 2013, he said.

Rain at the reservoirs and spreading grounds?

That’s the way the Storm Boss likes it.

Steve Scauzillo covers the environment and the drought for the Los Angeles News Group. He’s the current recipient of the Aldo Leopold Award for Distinguished Editorial Writing from The Wilderness Society. Follow him on Twitter @stevscaz or email him at




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