Aging Dams Raise State, Local Concern
Take a walk outdoors on a sunny afternoon with Bruce Julian of the Natural Resources Conservation Service (NRCS) and youll get an education. Standing on a jogging path that tops Northern Virginia’s Lake Braddock dam — lapsing into Washington DC bureaucratic jargon, Julian calls it “Dam 7” — the NRCS’s national policy coordinator explains what’s wrong with dams across the country by pointing out what this dams builders did right.
Since the passage of the Flood Control Act of 1944, the federal government has helped communities in 46 states construct over 10,400 dams for the purposes of flood prevention and watershed protection.
Once completed, these dams come under the care of local sponsors mainly soil and water conservation districts, counties and towns responsible for their operation and maintenance. More than fifty years have now passed and Julian says that despite adequate local maintenance, over 2,000 of these dams are approaching the end of their design life, filling with sediment and often holding acres of pooled water with corroding parts. Each year, hundreds more make the list.
In many cases, the stresses of sprawl have taken their toll. The replacement of trees and grass with roofs and asphalt has dramatically accelerated storm runoff. Downstream accumulations of homes, streets and shopping centers forced state-level safety reclassifications upon dams once built simply to keep meandering gullies from tearing up crop fields during heavy storms.
“Urban America has caught up with them,” says Ed Fiegle, president of the Association of State Dam Safety Officials.
While some dams need structural adjustments to meet the stricter codes for protecting lives and property downstream, others require substantial repairs and replacement parts.Work on these dams will be expensive: single projects could cost millions of dollars and neither dam sponsors nor states have adequate resources to make repairs.
Most officials are reluctant to say that the dams are “unsafe” and emphasize that the structures simply need to be brought up to date. But without federal assistance, observers say, upgrades will wait and they may soon face an even more costly catastrophe.
“I’m afraid that it is just a matter of time before we start to get … loss of life and property,” said NRCS Chief Pearlie S. Reed. At the winter meeting of the National Governors’ Association, Reed urged governors to examine the extent of the problem within their own states and work with local project sponsors and NRCS to come up with solutions.
A critical part of the problem is that under current law, NRCS is powerless to assist dam rehabilitation projects. Twin bills sponsored by Rep. Frank Lucas (R-OK) and Sen. Paul Coverdell (D-GA) would address the problem by authorizing $600 million over the next ten years for watershed dam rehabilitation.
The legislation would require the Secretary of Agriculture to rank priority projects and would authorize the federal government to cover 65 percent of a project’s total rehabilitation costs through NRCS.
States waking up
Despite the rise of what some call a movement to raise awareness about the potential for disaster, the issue is news to key state officials. “I don’t think the governors were aware of the breadth of the problem,” said Diane Shea of the National Governor’s Association.
Only Alaska, Delaware, Rhode Island and Washington do not have any small watershed dams. Georgia, cited frequently to illustrate the effects of urban growth in a once-heavily agricultural state, has 357 watershed dams, many of which will need a complete overhaul in order to meet standards and avoid eventual failures.
“There is simply not enough money on a local basis or state basis to rehabilitate these dams,” said Georgia Gov. Roy Barnes. Barnes notes that the state’s dam safety officials receive new complaints and requests for help every week.
Fiegle, who doubles as the manager of Georgia’s Safe Dams Program, says completed repairs and upgrades on two state-funded projects cost Georgia nearly $1 million apiece.
“We’re one of the few states that has actually funded repairs from our own pocket. But at the rate we’re going, we probably won’t be done for another 50 years,” he said.
Gov. Tom Vilsack of Iowa, home to 1,187 federally-assisted small watershed dams, stresses their importance to local safety and the $1 billion in annual national benefits that they provide through improved water quality, enhanced wildlife habitats, erosion and damage reduction, and recreation opportunities.
“We think it is a significant issue,” Vilsack said.
In February, Vilsack guided an NGA resolution in support of the Lucas and Coverdell authorization bills. The resolution called for a “collaborative partnership” between local, state and federal officials, a call echoed by dam officials.
The watershed structures built by NRCS account for only a fraction of the nation’s 74,000 dams, many of which were built on larger rivers and year-round streams for water supply or power generation rather than flood protection. But the knotty public partnerships that helped build the NRCS dams have prompted special attention and calls from dam safety experts for a united approach to restoring them.
“These sites were constructed as a state, local and federal partnership and most of the local sponsors … have the resources to do the routine maintenance. In some cases, they don’t even have that. But they don’t have the resources to ensure the integrity of the structures for the next fifty years. So they’re going to be in a deficit situation with a great deal of liability. That’s liability that they didn’t really sign on for,” said Dan Sebert, who directs district operations for the Oklahoma Conservation Commission.
NRCS agrees. “We want to maintain the partnership,” Julian said.
Waxing the hood versus rebuilding the engine
Julian calls Virginia’s Lake Braddock site one of the “Cadillacs” of the NRCS family. Like many of the NRCS dams built in the 1950s and 1960s, it was built to catch and control rainwater high in the watershed before it could pick up enough volume to cause erosion damage and threaten a flood lower in the valley.
Unlike many rural dams, which draw sprawl as an unforeseen development, Lake Braddock was planned as the scenic centerpiece of a new suburban community. Although it was built with growth in mind, it still goes through the same aging process as older, rural dams. “You can wax your car and change the oil, but eventually you’re either going to have to replace the car or totally rebuild the engine,” says Julian.
Constructed in 1970 at the end of a farm valley and fed by manicured streams, the lake lies about a twenty minute drive from downtown Washington DC when the roads are clear, but over an hour away during the weekday rush. In thirty years, as five more dams went up in the surrounding Pohick Creek Watershed, the area’s population jumped from 14,000 to 117,000.
Julian credits the county’s “progressive planning strategy” for the strength and relative safety of its NRCS dams. Zoning restrictions prevented the construction of new homes beneath the level of the dam’s crest, sixteen feet above the normal lake surface. The emergency spillway, which inspectors now find too narrow on many once-rural, reclassified dams, is broad enough for residents to play soccer and fly kites there. The co-sponsors, Fairfax County and the Northern Virginia Soil and Water Conservation District, have taken pains to maintain the dam’s plumbing and structural integrity, even removing saplings that grow along the shoreline.
Still, says Joe Haugh, director of Virginia’s Dam Safety Program, “there is no dam that is considered to be absolutely safe.” Haugh also gives Fairfax County high marks for the operation and maintenance of its dams not surprising for a suburban county considerably more affluent than the rest of the state. But he points to less rosy picture across the state and to non-NRCS structures that failed as recently as 1995. “Some of the big floods that we’ve had in the past could happen again,” he said.
Plumbing the depths of the problem
Even Cadillacs need an overhaul, and Lake Braddock will need attention before it turns 50 in 2020. But by national standards, Virginia’s portion of the problem is relatively small. Only 16 of its 144 watershed dams made a recent national priority checklist and Haugh says that “as a whole the NRCS dams are in pretty good shape.”
Not so elsewhere. The same NRCS estimate found that nearly half of Wisconsin’s 86 dams and more than one in every three Georgia dams need servicing. Nebraska, Iowa and Texas have almost 300 endangered or reclassified dams each. The estimated tab for repair and upgrade work averages $25 million but may run as high as $85 million per state.
Those figures, compiled by NRCS last year, are almost certainly underreported, says Fiegle. Georgia’s funding estimate topped the list of surveyed states, while Nebraska with more than double Georgia’s workload – was near the bottom at $3,600,000. For Fiegle, the explanation isn’t that Georgia’s dams cost more. Instead, securing funds from the Georgia legislature required dam officials to do some early homework that most states have yet to do.
The Lucas and Coverdell bills both set aside funds for a comprehensive NRCS assessment of repair and upgrade needs around the country, which Fiegle says may ultimately exceed $1 billion.
In all, 22 states running a thick band across the Plains, Midwest and the South host over 90 percent of these small watershed dams. Oklahoma has 2,094, including the nation’s oldest: Cloud Creek Site One, which celebrated its fiftieth birthday in July 1998. NRCS took advantage of the anniversary to sponsor a pilot rehabilitation at another site using state-of-the-art camera inspection technology.
Video probes of the Sergeant Major watershed, near the western Oklahoma town of Cheyenne, revealed a safety nightmare.
“On a structure that looked sound, that had been inspected and maintained as it was supposed to be … the inspection of the internal portion of the dam revealed deterioration of some of the concrete pipe. In some places you could actually see the soil surface of the embankment behind the pipe,” said Dan Sebert.
That spelled looming disaster, leaving experts to guess how many other structures house similar damage.
“We have a number that sit above state highways, county roads, in some cases maybe a city area itself. A couple are well out of city limits but are on a watershed or drainageway that goes into a populated area. There definitely would be loss of property and potentially some loss of life,” Sebert said.
Dam experts generally agree that the key to adequate solutions is in Congressional hands. They are generally optimistic that Congress will act on one of the two dam rehabilitation bills early in the 2000 session.
Fiegle hopes that attention to the small watershed dams in the system will prompt what he views as overdue attention at the state and federal level to the remainder of the nation’s invaluable dams. “We think there’s a real need out there to start addressing some of the infrastructure,” he said.
all photos courtesy of John Nagy
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