Georgia has more than 4,000 dams, ranging from mere mud fences to mortar mountains.
Many span streams that run for miles and, somewhere down the line, tie into water supplies. And most of these dams receive almost no regulatory oversight. The few hundred that do are on a waiting list two years long.
Within the past month, heavy rains have breached two dams in metro Atlanta, causing untold property damage and dislocating some residents.
Just last week, a small dam in Sandy Springs broke open, damaging a gas line on Roswell Road and forcing the evacuation of a nearby apartment complex. Crews spent all day Thursday pumping water from the pond to keep the dam from failing completely.
Although its failure disrupted traffic and kept some residents from their homes for two days, the dam is too small to fall under any regulatory review.
Last month, a dam at the eastern edge of a 10-acre pond in Cumming burst after storms dumped more than 4 inches of rain on the area. Water and mud gushed through the gap, spilling into Little Ridge Creek and washing out part of Sanders Road before flowing into Lake Lanier.
“It’s a little scary,” said Michael Leahy of Cumming, who lives on a cove on Lanier that was beset with tons of silt when the dam broke on Lake Alice on May 19. About 50 homeowners live along the cove and reported the water turned “pumpkin orange” after the incident.
“I talked with some of the neighbors and we had no idea there was a dam there,” Leahy said.
The Safe Dams Program of the EPD monitors all but the state’s largest dams, those operated by the U.S. Army Corps of Engineers.
Safe Dams is responsible for 4,053 dams throughout Georgia. Of that number, 484 are labeled “high hazard,” meaning they warrant annual inspections because a failure could threaten lives.
The agency used to inspect these high hazard dams every year, but cutbacks in staff have made that impossible. Back in 2006, the office had 11 employees and a budget of $727,000. Today it has six employees, including one secretary, and a budget of about $600,000.
And while staff and funding have gone down, the number of high-hazard dams has gone up.
“Until about three years ago, we were inspecting them on an annual basis. But with our staffing, we’ve cut it back to doing half each year,” said Tom Woosley, Safe Dams Program manager.
Of the agency’s five field inspectors, three are assigned to high-hazard dam inspections, which include reviewing plans, scanning for damage and checking spillway capacity.
The two other inspectors, called classifiers, track the 3,600 low-hazard dams to monitor whether conditions have changed to warrant reclassification. If, for example, a new development has been built near a dam, it could justify an upgrade to high-hazard status.
These low-hazard dams are supposed to be inspected every five years, but they’re not. The agency has been running a backlog in the hundreds over the past several years.
“There’s still a hiring freeze on, so we’ve got to justify that it’s a critical hire to see if we can get someone here,” Woosley said.
The agency has a backlog of 115 dams recently upgraded to high hazard that have yet to be fully assessed so their owners know how to address them. There are also just under 500 low-hazard dams waiting for further study because they were flagged for potential upgrade to high-hazard status.
“Sooner or later, something’s going to go wrong with a structure and it’s going to hurt somebody,” said Ed Fiegle, an expert in the field.
When Fiegle retired as director of the Safe Dams Program in 2010, he left with 32 years of experience and a national reputation.
Fiegle said the state is asking for trouble by not paying closer attention to the potential threat to life and property these dams pose. His experience in the field convinces him that most of the unregulated dams were either never built right to begin with or have not been maintained properly.
“Probably 95 percent of them don’t receive any type of regular maintenance,” he said. “If everybody’s lucky, the structures that fail will have nothing below them.”
Metro Atlanta’s recent rain totals — 7 inches above normal for the year — have tested some dams, EPD officials said. But the torrents in the fall of 2009 pushed many to the limit.
The department inspected 96 high-hazard dams in the area following the September 2009 deluge. Water washed over the tops of four of the dams. Another 46 had their emergency spillways activated and a couple of them — Lake Tara and the Snake Creek Reservoir in Carrol County — came close to failing.
Some believe the threat will intensify as development continues and soft ground gives way to new asphalt. Increased runoff intensifies stream flows and the pressure against dams, said Jason Ulseth, technical programs director for the nonprofit Chattahoochee Riverkeepers.
“You have a lot of new impervious surfaces which weren’t in place when these dams were built,” he said. “It doesn’t take more than a big shopping center to go in and wash out a dam.”
Dam Safety Program workload
|Year ||State regulated dams||High-hazard dams||Employees|
Source: Georgia EPD