Urban River Seeks to Find Its Way : Environment: The river’s losses have meant gains for Mission Valley. But naturalists say large-scale development should never have been allowed in a flood plain.

If Mother Nature were to tour Mission Valley, she would be hard-pressed to recognize the San Diego River. The river has been rerouted, narrowed, augmented and, in one case, buried--all in the name of progress.

For landowners, developers and San Diegans who live, work or travel in Mission Valley, the river’s losses have generated obvious gains, including improved freeway access and a road system that is less likely to flood during winter and spring rains. Hundreds of acres of land that were held captive by the threat of flooding now are being freed for widespread development.

Most naturalists believe that large-scale development should never have been allowed in the valley that doubles as a flood plain for a notoriously temperamental river. But, in Mission Valley, “the fact is that a big city is here,” said Philip Pryde, a San Diego State University geography professor who has followed river developments since the early 1970s. “This is, and has been an urban area.”

City, state and federal regulations now require developers to make amends for wetlands that are lost to development. The San Diego River today is a piecemeal of different approaches to the reconstruction of wetlands and an illustration of how difficult it is to mitigate damages when so little open space remains.

Solutions are hard to find because naturalists are at odds on how to preserve those remaining wetlands. Some maintain that wetlands simply can’t coexist with massive development. Others maintain that, with assistance from mankind, the remaining natural habitats can thrive.

In Mission Valley, the signs of change--and, in some cases, outright abuse--are everywhere.

One developer recently made way for a new road by illegally bulldozing part of a tree-planting project that was intended to mitigate environmental damages caused by another developer.

During a highway widening project, the California Department of Transportation altered the river’s course--and buried the old riverbed beneath tons of concrete along Interstate 8 and its access roads. In another project, sensitive wetlands were destroyed to complete an interchange.

To “mitigate” those lost wetlands, Caltrans has, with partial success, tried to recreate wetlands elsewhere in the valley. One 7-acre parcel to the east of San Diego Jack Murphy Stadium seems to be thriving.

Seven years ago, the tract was a highland area that had served as a dumping ground. Caltrans carted off tons of earth and created a wetlands complete with willows and cottonwoods. Ground cover is flourishing, and the tract is home to many birds and animals.

A more recent attempt near Morena Boulevard, however, met with little success: Instead of trees and native habitat, weeds have taken over. “It looks terrible,” said one biologist who has toured the project.

Developers and Caltrans, however, aren’t the only parties to have altered the river’s makeup.

The San Diego River increasingly is being used as a “pipeline” to carry urban runoff generated by many nearby San Diego neighborhoods. The volume of urban runoff channeled into the San Diego River by sewers, ditches and roadways has risen steadily as the county has become increasingly urbanized.

Other proposals would place additional demands upon the river valley.

The county water authority recently suggested that the San Diego be used to carry reclaimed waste water from a treatment plant in Santee to neighborhoods near the river that need irrigation water. And, the county’s light-rail transit system eventually will lay tracks that parallel the river.

Despite mankind’s incursions, some stretches of the river valley still resemble the river of nature. Near Padre Dam in the Mission Trails Regional Park, graceful willows and cottonwoods form leafy green canopies over river banks that are covered by a variety of native vegetation.

There, the landscape constantly changes during the rainy season, as floodwaters re-sculpt the plain. Flooding is an integral part of the valley’s “self-maintaining system,” according to John P. Rieger, a Caltrans biologist who supervises mitigation projects for the state.

But flooding, natural though it may be, is anathema to landowners and developers.

Along a mile-plus stretch of the river between Interstate 805 and California 163, construction crews are completing the privately financed, $30-million First San Diego River Improvement Project, known by the acronym FSDRIP--developers and regulators pronounce it FIZZDRIP.

The project is the most obvious example of how increased urbanization has changed the San Diego River valley.

When completed later this year, the flood channel will protect nearby lands from the torrent of water--now estimated at 36,000 cubic feet per second--that would rush into the river valley from nearby neighborhoods during a 100-year storm. The channel is large enough to handle the increased volume of water (as much as 49,000 cubic feet per second) that might be produced in a 100-year flood.

With the flood-control channel in place, hundreds of nearby acres are for the first time open for full-scale development. And, during the next 20 years, landowners and developers will erect several new hotels, a handful of residential developments and a slew of office buildings.

Landowners and developers to the west of California 163, where flooding is equally severe, are considering a FSDRIP-like channel that would open up hundreds of acres to development.

For motorists who view FSDRIP from cars whizzing along SR 163, the flood channel appears to bring order to the San Diego, a river that, by human standards, seems chaotic.

Gone is the shallow, meandering river that nearly disappeared during dry months. Gone is the thick canopy of trees that largely shielded the river from sight. And gone, at least for the present, are animals--including fox, raccoon and possum--that used to live along that stretch of the river.

Engineers have fashioned a hydraulically designed flood-control channel with carefully sculpted islands and massive earthen walls designed to handle torrents unleashed during a 100-year flood.

New bridges have been built along Stadium Way and Mission Center roads, which were prone to flood even during relatively light rainfalls. When FSDRIP is completed, it will take at least a 10-year flood to close the roadways, said Howard Chang, a San Diego State University civil engineering professor who designed the project.

FSDRIP is first and foremost a flood-control channel.

But regulators have demanded that the project’s owners also attempt to return the river to its natural state, a contradictory demand, given a flood-control channel’s main purpose of moving floodwaters downstream.

That requirement is in keeping with a growing, national awareness that wetlands must be preserved, even in areas where development is occurring, said Jack Fancher, a biologist with the U.S. Fish & Wildlife Service’s Laguna Niguel field office.

Consequently, FSDRIP’s banks and islands are being planted with native vegetation that, its designers believe, will thrive in the river’s environment.

Within five years, recently planted saplings will restore the leafy canopy that was lost when the original riverbed was destroyed, according to Brad Burkhart, a biologist with ERC International, a consulting firm that is supervising the habitat restoration.

As part of the restoration effort, cattails, reeds and other native plants that thrive in the region’s Mediterranean climate are being planted along the channel to replace lost wetlands.

In a bow to the city’s growing need for park space, the San Diego River’s new banks will include bicycle paths and spaces for picnic tables. There is also space for two parks.

Recreational opportunities in the flood-control project, however, will be restricted, according to Linda Johnson, a city planner who oversaw valley developments for the past five years. “We don’t want people in there,” Johnson said. “It’s primarily a wildlife refuge.”

But, even with those restrictions, naturalists wonder if FSDRIP can serve a dual purpose by replacing the riparian habitat lost during construction of the channel.

“FSDRIP is one case that will be looked at as to whether or not compensation, or replacement of lost habitat, works,” Fancher said. “This is the first time that a project this big has been undertaken.”

At first blush, it is difficult to believe that the channel will ever resemble the wetlands that were bulldozed to make way for the project.

The flood channel’s steep walls are “not a very pretty sight for many of us,” according to Bill Tippets a California state parks senior resource ecologist. “It’s a narrow channel, and it doesn’t emulate the natural conditions all that well.”

Rieger, who applauded regulators for demanding that FSDRIP incorporate native plants and trees, maintains that the channel “doesn’t look like anything that I’ve ever seen before.”

But Burkhart believes that doubters will be silenced as plantings mature and the channel begins to look more like a river. Burkhart also believes that, once the plantings are securely in place, they will prosper--even if the channel is inundated by a 100-year flood.

Regulators have forced landowners who are paying for FSDRIP to carefully monitor growth of the trees and plants on the channel’s walls and islands. Plantings that fail to thrive must be replaced, Burkhart said, and growth must meet carefully established guidelines.

Although many naturalists are critical of FSDRIP’s design, all acknowledge that the project is more desirable than the concrete-lined river channel that first was proposed during the late 1960s and early 1970s.

“Nobody wanted a (concrete-lined) Los Angeles River running down the middle of Mission Valley,” said Linda Johnson, a senior city planner who was involved with projects in the valley for the past five years.

Landowners subsequently “called for a grass-lined swale, which would strip out all the native vegetation and replace it with (a channel) lined with grass,” Fancher said. “That was opposed” by federal regulators.

Developers then proposed “what I call the manicured, park-like setting,” Fancher said. “They were willing to allow some trees, but it was going to look like the classic park with mown lawns, park benches and the like.”

Eventually, developers and regulators hit upon a compromise: a flood channel that also attempted to restore wetlands lost in order to provide flood protection.

The engineers designed a system that will deal with a 100-year flood without property damage, but also without damage to the habitat, Fancher said. He said developers must meet “a lot of performance standards designed to ensure that the natural habitat thrives. “They just can’t walk away from it if it doesn’t work,” Fancher said.

Lessons learned during the decades-long debate that led to FSDRIP will come into play as development continues in the western reaches of Mission Valley. City officials since have developed a wetland management plan that other developers will have to comply with, Fancher said.

“FSDRIP is going to be a good test case,” acknowledged Gary Yagade, a consultant for Atlas Hotels, which will begin work on a two-phase Mission Valley development during the 1990s. That project, which stretches between Fashion Valley Road and California 163, will incorporate a flood channel that is “similar” to FSDRIP’s, Yagade said.