January 7, 2010
by April Reese
Six months after workers filled a canyon south of San Diego to enhance border security, California environmental officials say the controversial project is damaging a nearby estuary.
Customs and Border Protection officials completed the Smuggler's Gulch project in July.
Contractors filled the gulch, long a conduit of illegal activity, and built a new 15-foot-high fence and an access road across it. Once a deep canyon, the gulch is now bridged by a 100-foot-high earthen berm.
Department of Homeland Security officials say the berm allows agents to drive straight across what used to be a formidable obstacle, providing much quicker response times and a safer route to handle law enforcement and public safety emergencies. But while the berm -- as high as some of the West's towering concrete dams -- and accompanying fence may stem the flow of illegal immigrants and drug smugglers, those benefits have come at a significant environmental cost, critics say.
During peak rain events, barren slopes along the newly filled Smuggler's Gulch erode, sending sediment downstream into the Tijuana River estuary.
Like the other drainages in the rugged "border highlands" region, as the westernmost stretch of the U.S.-Mexico border is called, Smuggler's Gulch and other nearby canyons funnel streams from Mexico northward into the Tijuana River and its estuary (Land Letter, Jan. 15, 2009).
The estuary, which has undergone a multi-decade restoration effort, encompasses a national wildlife refuge and state parklands and is home to a number of endangered bird species, including the light-footed clapper rail, the California least tern, the least Bell's vireo and the American peregrine falcon.
California regulators and environmental groups, who warned DHS of the potential adverse effects of the $58 million project when it began, say their fears of damage to the estuary from an influx of eroded sediment are now proving true.
"The river valley keeps getting more and more sediment in it," said Jim Peugh, conservation chair of the San Diego chapter of the Sierra Club. "It has long-term flooding effects and long-term habitat effects for both the river valley and the estuary it flows into."
CBP was able to undertake the project without adhering to state or federal environmental laws due to waiver provisions both in a 1996 law pertaining just to the Smuggler's Gulch area and the REAL ID Act of 2005, which extended the waiver authority to the entire border region (Land Letter, Sept. 22, 2005).
As a result, regulators had little authority to address environmental problems.
"In some places, erosion control practices were not properly employed, in my opinion, and there's been significant erosion," said David Gibson, executive officer of the San Diego Regional Water Quality Control Board. "Normally I would have issued a violation for failing to meet the [state] standards for construction, but in this case we couldn't do that."
After meeting with CBP and its contractors, however, officials agreed to fix those problems, Gibson added. "Now that they've seen where the weak spots are, they're addressing them," he said.
Most of the sediment choking the estuary is flowing across the border from Mexico, but the fence project has exacerbated the problem, Gibson said.
"This was an extremely large construction project," he noted. "You just can't have that much earthmoving without having major problems."
DHS spokesman Claude Knighten said contractors did employ erosion barriers, such as waddles, and attempted to plant soil-stabilizing vegetation. But some of those efforts did not work as well as officials had expected, he acknowledged.
Some of the seeds that were planted on the newly created slopes, for example, did not take root due to mistimed watering. Contractors have since reseeded those areas and plan to better irrigate the plots to make sure the plantings succeed the second time, Knighten said.
The state is also considering installing trap structures to help keep sediment out of the estuary as part of the larger restoration effort, Gibson added.
Otay Mountain problems
Further east, in the federally protected Otay Mountain Wilderness, another new stretch of fence, along with the new road needed to patrol it, also is causing environmental damage that probably would not have occurred without the waiver.
Construction workers have removed about 100 rare Tecate cypress trees there that survived a 2003 wildfire that wiped out about 68 percent of the tree's habitat. And truck traffic has sent clouds of dust into the air, coating the tree's leaves, which provide food for the equally rare Thorne's hairstreak butterfly.
As the result of a lawsuit from the Center for Biological Diversity, the Fish and Wildlife Service is considering whether to protect the butterfly under the Endangered Species Act.
Knighten of CBP said crews are now wetting the roads to reduce dust. "We'll be monitoring the dust to make sure there aren't any problems," he said.
The Smuggler's Gulch and Otay Mountain projects were part of a far-reaching, congressionally mandated effort to shore up the U.S. southern border with hundreds of miles of new fencing from Texas to California. About 633 miles of new fence have been completed so far, at a cost of $2.4 billion.
Critics say the Smuggler's Gulch project will push illegal border activity further eastward and to the Pacific Ocean, where crossers will take to the water to get around the fence.