Building
boom in flood-prone foothills Aug. 2--A building boom continues in north Fontana and Rancho Cucamonga despite inadequate protection from post-fire flood conditions existing across the foothills from Highland to Upland. By Guy McCarthy, San Bernardino County Sun, Calif. Aug. 2--A building boom continues in north Fontana and Rancho Cucamonga despite inadequate protection from post-fire flood conditions existing across the foothills from Highland to Upland. Work has yet to begin on $6 million in emergency projects to enlarge or repair flood control basins and channels that are not engineered for severe storms in San Gabriel and San Bernardino mountain watersheds still recovering from the the October fires. More than a third of the emergency funding is aimed at improving flood control facilities that protect Fontana and Rancho Cucamonga residents. The summer monsoon season is not over. Forecasts indicate intense storms are possible again later this year, said Richard Minnich, who studies fire science and climatology at UC Riverside. "We've got a higher than normal probability for heavy rains this coming winter," Minnich said. "We're talking about concentrated, enormous rainfall over a short period of time. Some of the most intense rainfalls in the world fall on the south front of the San Bernardino Mountains.' Minnich and other scientists who monitor long-range weather forecasts question the wisdom of continuing to build homes in post-fire conditions while emergency flood control projects are only in the design phase. "I don't think there's a way ... they're going to finish those measures in time," said U.S. Geological Survey geologist Doug Morton, who has mapped the local mountains and alluvial fans below them. "If I were in city government and flood control came in and said the facilities are inadequate, that emergency projects are called for, I would be concerned about class-action lawsuits," Morton said. "The responsibility lies with the cities allowing homes to be built.' On Dec. 25, post-fire flash floods killed 16 people in Waterman Canyon north of San Bernardino and in Devore and washed out a key mountain evacuation route that remains closed for repairs. Heightened flood conditions from last fall's Grand Prix and Old fires are expected to remain for three to five years. "The situation is an exaggerated threat until the watersheds recover," said Patrick J. Mead, interim director of county public works. "Even though it's a unique and infrequent situation, it's occurring.' Flood control work on the emergency projects should start in September and be completed before rains start in November or December, Mead said Friday. Debris basins scheduled for emergency excavation include Deer Creek above Rancho Cucamonga; four San Sevaine basins between Rancho Cucamonga and Fontana; the Devil Canyon complex in northwest San Bernardino; and Harrison and Daley basins in San Bernardino, according to county documents. A 1,330-foot stretch of San Sevaine channel, between Fontana and Rancho Cucamonga, was damaged in last winter's floods. It must be demolished and rebuilt. Other emergency measures include installing racks upstream from basins to catch trees, limbs and other debris that can clog the basins. The amount of sediment and run-off that could come out of the mountains in a heavy storm or series of storms this winter could easily overwhelm existing flood control basins, Minnich said. "Remember, that Christmas storm was a 10-year event at most," Minnich said. "We're looking at forecast potential that could be worse.' Post-fire flash floods can pack up to 50 times the boulders, rocks and mud an identical storm would generate in normal conditions. Fast-moving rock floods can cut through pavement, concrete and steel. Minnich used the example of Harrison Basin in San Bernardino to illustrate what could happen if severe storms hit this winter. In 1980, four storms overwhelmed the basin each time, damaging 40 homes. Residents successfully sued the city and county. The street below the basin is a now a grassy flood channel. "San Bernardino's still paying for what happened in Harrison Canyon," Minnich said. "We could have a whole bunch of Harrisons, all along the south front of the mountains. They don't have room for any more houses. If they put more houses in, they're asking for it.' James Slosson, a former state geologist who has authored studies on natural hazard litigation, advised caution. "They should stop building at least until they finish the flood control measures," said Slosson, who worked under Gov. Ronald Reagan in the 1970s. "They're taking chances, even if it doesn't rain this winter. Who's going to pay for the damage if they get gully-washed?' At first glance, newly built housing tracts in the foothills north of the extension of Interstate 210 appear to be islands of security in the midst of foreseeable hazards. Fire-resistant roofs and walls, elevated foundations, and sidewalks that double as flood control channels protect these homes. But the fortified communities in northwest Fontana and northeast Rancho Cucamonga are not engineered for intense post-fire flash flooding. They rely on flood control structures higher up the hill. Outside the walls of the new developments, natural hazards are obvious. Blackened stands of chaparral, burned in the October fires, pepper the rock-covered slopes. Creek beds, modified or not, are choked with boulders. Signs warn of "Extreme Fire Danger' or "Danger Flood Control Keep Out." Fenced flood control channels snake in and out of the tracts. Other signs alert the public to plans for building 120 homes, or announce public hearings on environmental impact reviews for yet more home building proposals. The Army Corps of Engineers says this region is home to one of the most volatile fire-erosion complexes in the world. Simply put, the vegetation and weather conspire to burn. In the aftermath, intense storms unleash rivers of rock and sediment onto the alluvial fans. "There's gotta be acceptable risk," said Frank Williams, a spokesman for the multibillion dollar home building industry in southwest San Bernardino County. "We make homes today safer than ever before. But how can we protect ourselves from acts of God?' Malissa McKeith lived for years below Deer Creek Basin, a flood control structure high on the giant alluvial fan that comprises most of Rancho Cucamonga. She's spent hours in court and public meetings fighting federal, state and local authorities over the basin's capacity, which she and other residents claim is undersized. "Flood Control is promoting a few half-baked upgrades that won't make anyone safer but will give developers the cover they need to keep building," McKeith said. "Change will come only after a flood when a grand jury is convened and someone goes to jail. Our government is supposed to protect people not the stock price of builders." Fontana Mayor Mark Nuaimi said he hadn't heard about the emergency flood control measures. "I'm not familiar with the county projects," Nuaimi said Friday. "We're continuing to build, but I'm not aware of any emergency projects in those areas. No one has indicated we should hold off until they're completed.' Rapid growth has resulted in less-than-prudent building plans, said Fontana Planning Commissioner Kenneth Galasso. Fontana is one of the fastest growing cities in the nation. "There are pressures that are pushing us out a little further than we should be," Galasso said. "But I'm certain our staff has a handle on flood control. The only project that's an issue is Coyote Canyon. We're not burying our heads in the sand. We're not ignoring the problems. Hopefully the builders are taking these things into consideration.' Rancho Cucamonga Planning Commissioner Larry McNiel hadn't heard of the emergency measures either. "We've already done a bunch of site work installation on flood control facilities," McNiel said. "We've been trying to protect the homeowners up here. We are nonetheless living on an alluvial fan, and we're going to have run-off on these slopes. The best we can do is try to control it.' Inadequate flood control is a public safety issue, but growth is inevitable, said Rancho Cucamonga Mayor Bill Alexander. He was also unaware of the emergency measures effecting his community. "I'm not saying it's a good idea to keep building up the hill," Alexander said. "I would love to see a large, open space of land north of Rancho Cucamonga and Fontana. But until we get to a point where private interests can afford to set aside the land, we're going to see more development."
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