Tuesday, May 29, 2001  
THE ARROYO SECO goes from its natural soft bottom to a concrete channel in this stretch of the river. Area environmentalists want the concrete removed. (Staff Photo by WALT MANCINI)
Charting new course for Arroyo

Environmentalists eye plans for restoring river

By Lisa Faught
Staff Writer

PASADENA -- The Arroyo Seco once meandered through the land, wending its way like a snake through the grass.

But when the rains came, the river turned into a froth of water, sometimes flooding the land and washing away homes.

So in 1938, the U.S. Army Corps of Engineers set about taming the arroyo with a channel of concrete and a system for controlling the water. When water collected behind Devil's Gate Dam, operators slowly released it into the channel in a straight shot to the Los Angeles River.

Over the years, the channelized river fell victim to growing mountains of trash, homes inching closer to its banks, scars of graffiti on its sides and pollution from urban runoff.

Now the river has come full circle. Local environmentalists are working to tear out the concrete and return the river to its natural state.

"Part of our responsibility is to learn how to be better stewards of the Earth," said Tim Brick, of the Arroyo Seco Foundation. "It took a long time to mess it up and it will take a long time to restore it. But the support is there to do it."

The Arroyo Seco Foundation and North East Trees is on the brink of finishing a study of the river -- its concrete casing, its water, its wildlife, its future.

For the last nine months, a small army of "ologists" have worked to devise a holistic system for restoring the river to what it once was. They envision a swath of green cutting across the urban landscape from Pasadena to Los Angeles, a haven for people and wildlife.

But can they do it?

"We haven't heard 'no' yet," said Lynne Dwyer, executive director for North East Trees.

The plan, estimated to cost $600,000, is the first to look at the Arroyo Seco in its entirety, from headwaters to mouth.

The two organizations initiated the report in hopes of scoring a chunk of the $4.1 billion in state funds dedicated to improving parks and water quality. They aim to fold some of their goals into a master plan for the Los Angeles River and three master plans for a 14-mile stretch of the river in Pasadena.

Last Thursday, the Arroyo Seco Foundation and North East Trees released the first of their recommendations, which include removing the concrete channel below Devil's Gate Dam; killing off exotic plants; buying land along the river for parks and trails; and restoring the habitat for native species, such as the endangered arroyo toad and steelhead trout.

"(Trout) jump waterfalls, they dodge orca whales, they pretty much do it all," said Matt Stoecker, ichthyologist for Conception Coast Projects. "If we unbuild it, they will come."

The move to restore the arroyo comes amid a nationwide renaissance of rivers. In the Southland, the San Gabriel Mountains Regional Conservancy is working to restore the San Gabriel River, and a coalition of groups is planning a greenbelt along the Los Angeles River.

The Arroyo Seco bubbles to the surface at Red Box in the San Gabriel Mountains and flows downstream to Devil's Gate Dam, where it is funneled into a concrete channel and shunted to the Los Angeles River.

But along the way, chinks emerge in the concrete armor, giving way to the soft bottom of the river. These breaks in concrete, where the river already runs naturally, are what give environmentalists hope. They see a burbling stream flanked by lush vegetation, like in the lower Arroyo Seco, where a restoration project has returned the landscape to its native habitat.

Hydrologists and fluvial geomorphologists are in the midst of plotting a new path for the river, sans concrete. Michael Drennan, engineer for Montgomery Watson Harza, envisions the river meandering across the Brookside Golf Course, occasionally spilling over onto the green when the rains get fierce. The course is a natural flood plain, and could serve as a spreading basin when the river rises too high, he said.

"It is technically feasible, yes. But the question is, is it politically and economically feasible?" Drennan said.

Tearing out the concrete could mean liability for the cities along the banks of the river, if the water by chance damages a home or building, according to Pasadena's Department of Public Works. The amount of sediment that slides off the mountains each year is one factor to consider, and the likelihood that the river will be dry for much of the year is another.

But despite all the work, much is left to be done. The Arroyo Seco Foundation and North East Trees have listed more than 70 projects along t**he Arroyo Seco and now must figure out which comes first, over the next 25 years. Until they identify which projects are most likely to go forward and find the money to do it, details such as what to do with houses are on hold.

"We can spend a lot of money fixing up the flood channel, or we can spend a lot of money trying to build a more natural regime," Brick said. "No one really defends the concrete that much."

-- Lisa Faught can be reached at (626) 578-6300, Ext. 4496, or by e-mail at lisa.faught@sgvn.com.


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