A great blue heron stood motionless at dusk, its long pointed beak poised to strike a tadpole or minnow in the shallow green water. Behind the elegant long-legged bird, red-winged blackbirds flitted up and down in the wind, bending the tall cattails. The heron, between sand bars thick with mulefat and young willows, waded in a river carpeted on its banks by clover-like weeds.
One might expect to stumble upon this solitary wetland scene in the wild, perhaps behind a duck blind in some wildlife preserve. But the roar of cars passing above on the Pomona Freeway is a noisy reminder that this riverine landscape is part of a five-mile-long habitat that has gradually sprung back to life along the San Gabriel River over the last 15 years.
Running southeast from the confluence of the river and Walnut Creek near Baldwin Park through a patchwork of south San Gabriel Valley cities down to Pico Rivera, this greenbelt of sand bars and slow-flowing water is a paradox of nature's resiliency hemmed in by concrete banks, housing tracts and factories.
Some of the contrasts--an abandoned shopping cart sitting amid reeds in the water, a rusted bumper in the river mud--are obvious. Others, including an occasional bicyclist or jogger traversing the miles of man-made paths and trails, are subtler reminders that civilization is not far away.
The present-day lushness of the river habitat belies a dramatic cycle of transformations that began in the 1950s when the once-wild river, historically known for overflowing its banks and causing floods, was tamed.
Men using heavy equipment cleared the river of life-sustaining plant life, creating a flood-control channel with a sandy bottom and concrete banks. Thus began a continuing struggle in which plants would spring up, only to be periodically stripped clear by bulldozers, then rise again. The habitat that flourishes today was created gradually and accidentally as the San Gabriel River became a conduit for replenishing stores of underground drinking water further downstream.
This still-youthful habitat may be about to undergo another transformation. About half of the wetlands area may soon be destroyed as part of a clearing operation by the Los Angeles County Department of Public Works (DPW), which manages the channel upstream from the river's confluence with San Jose Creek near Industry.
The DPW says that its portion of the channel must be cleared of vegetation to control the growth of brush and trees that might undermine bridges and cause flooding downstream.
Negotiations Under Way
However, the state Department of Fish and Game, which oversees fisheries along the river, has been alerted to the threat by environmentalists and has asked that the DPW save a 10-foot swath of vegetation at the channel's edges to ensure that the wildlife now thriving there will survive the operation. A DPW spokesman said the agencies are negotiating and are expected to reach an agreement next week.
In contrast to the county, the Army Corps of Engineers, which manages a 2-mile section of the channel south of San Jose Creek in the 1,400-acre Whittier Narrows Recreation Area, says it will allow the portion of the habitat it controls--surrounded by South El Monte, El Monte, Rosemead, Montebello and Pico Rivera--to flourish in a way that will not damage the channel.
David Drake, a fisheries biologist for the state Department of Fish and Game who supports the corps' concept of channel management, believes the habitat is a valuable wildlife resource that should be protected.
"In Southern California, we realize that we have very limited riparian (river) habitats," said Drake, who monitors the health of the river's fisheries. "So it's very important to protect those few areas that remain" for waterfowl, fish and other animals.
The view that such habitats are in themselves endangered species is supported by a report prepared last year for an Assembly subcommittee that concluded that more than 90% of the state's coastal and inland wetland areas--estimated at 3 million to 5 million acres--has been destroyed. Along the state's 1,100-mile coast, the report said, only one-fourth remains of the 300,000 acres of wetlands that once existed.
Links in Food Chain
Drake said that the San Gabriel River habitat's aquatic plants provide the links of a complex food chain, beginning with fresh water plankton, snails, crawfish, aquatic insects, several species of fish and amphibians.
Anglers who have found their way back to this spot say they regularly hook carp, channel and bullhead catfish, and, on occasion, red-eared sunfish and trout. Drake said fish enter the river after escaping from dams upstream. Once in the river, he said, some of the fish like carp and catfish reproduce, making it a popular urban fishing ground that must be patrolled by state fish and game wardens.
One of the fishermen, Jose Segura Gabina of La Puente, can attest to the habitat's vitality. Gabina, who has fished there regularly for about six years, said he once caught 48 carp and catfish in one day. He said the fish, which he takes home and fries, fins and all, "thrive here because there's enough for them to eat."
Bird watchers spot several species of migratory waterfowl, including mallards, red heads and green-winged teals, and wading birds like snowy egrets, black-crowned night herons, green herons and dowitchers. The habitat's overgrown sandbars, which are periodically shorn of vegetation by winter flood waters, offer food for orioles, cardinals, white-tailed kites and red-tailed hawks.
Coyotes, Foxes Observed
Besides providing a haven for birds, the river bed--about as wide as 1 1/2 football fields--is used by coyotes, foxes, raccoons and other small mammals as a corridor to and from the foothills of the San Gabriel Mountains, said Rick Harlacher, an ecologist with the Army Corps of Engineers.
That the habitat exists at all is in great measure an accidental byproduct of a water conservation program started 26 years ago to divert water to severely depleted aquifers fed by the San Gabriel River.
Donald Nichols, a water conservation engineer for the DPW, said that the county agency launched a conservation program in 1959 in which water provided by the Metropolitan Water District was diverted to settling grounds adjacent to the San Gabriel and Rio Hondo rivers.
Nichols said the job of replenishing the ground water went to the Central and West Basin Water Replenishment District, a public agency financed by municipal and private water agencies. Since its founding, he said, the replenishment district has diverted about 100,000 acre-feet of water per year to these settling grounds. The San Gabriel River--connected to the Rio Hondo by an east-west channel immediately behind the Whittier Narrows Dam--carries the water to the district's settling grounds.
Bolstered by runoff from winter rains and water released by county reclamation plants and by the DPW upstream during the summer, the river passing through Whittier Narrows has enjoyed an abundant year-round supply of water for the last 15 years, Nichols said.
Environmental Concern Began
The latest phase of the river's evolution began in 1969 when Congress passed the National Environmental Policy Act, which required the Corps of Engineers to take into account the environmental impact of its flood control projects.
"Although we haven't done anything to encourage it," Harlacher said, the 1969 law and subsequent federal and state laws have given the Corps of Engineers the impetus to protect the habitat's return.
Despite its benefits, he said, an environmentally sensitive concept of river management has not been widely accepted by flood control engineers.
"There's a lot of resistance to doing anything like this. The engineers (in the corps and DPW) have been trained to clear channels, that flood control and habitat protection are mutually exclusive," Harlacher said.
However, Rosalin Robson, a DPW spokesman, said that the flood control agency has become increasingly sensitive to environmental concerns.
Joint Uses Welcomed
"I don't think our organization takes a traditional view of flood control," Robson said. "We're always interested in promoting joint uses of our facilities, provided they do not interfere with the primary purpose of the flood control channels."
To that end, she said, the DPW built more than 60 miles of bridle paths and bikeways along the Rio Hondo and San Gabriel rivers in 1979, providing facilities that are enjoyed by thousands of people each year. The department also encourages fishing in the reservoirs it manages, she said.
But a rusting bumper half-buried in river-bottom mud is a reminder that despite its evolution from a seemingly sterile flood control channel to a wildlife and recreational resource, many still view the river as little more than a dumping ground, Harlacher said.