The team effort that saved a Columbia dam

Mindful of potential danger to communities downstream, workers and WildeWood residents preserved the dam with resources including pumping, trenches, rocks, 1-ton sandbags and a retaining wall.
Mindful of potential danger to communities downstream, workers and WildeWood residents preserved the dam with resources including pumping, trenches, rocks, 1-ton sandbags and a retaining wall. tglantz@thestate.com

As rain poured and waters in Beaver Dam Lake rose on Oct. 4, Jim Lehman climbed into his orange kayak to clear pine straw clogging an opening that allows water to escape the dam.

Lehman’s efforts were futile during a storm that dumped three months of rain on the Columbia area in a single day. It was a sign of the difficulties to come for Lehman and his neighbors, who would spend the next four days struggling to keep the 24-foot dam in the WildeWood subdivision from bursting.

“I have never failed at so many things in my life,” Lehman said.

Elsewhere that weekend, 18 dams in Richland and Lexington counties completely failed, flooding hundreds of homes, washing out roads and closing dozens of businesses. But the dam at Beaver Dam Lake held its water, thanks to the help of a local landscaper, a highway contractor, an electric utility, state regulators, the S.C. National Guard and the U.S. Department of Homeland Security.

They brought manpower, construction equipment, hundreds of sandbags and several tons of rock. They also huddled with neighborhood leaders about how to relieve water pressuring the 52-year-old earthen dam.

Success was not certain, and no one was quite sure how much damage could come from the dam failing.

Crews worked around the clock for several days as repeated attempts to secure the dam failed. Police called homes immediately downstream on at least four occasions to suggest evacuations.

Experts considered how a rush of more than 90 million gallons of water along Jackson Creek could burst dams already damaged by the historic storm.

“We were trying to help people below us,” Lehman said, “people we didn’t know.”

Dam was in good shape

The lakes in WildeWood are an attraction in the large northeast Richland County subdivision. Maps show more than 20 lakes and ponds throughout the neighborhoods.

WildeWood includes six dams regulated by the state. The Beaver Dam Lake dam, known formally by state officials as WildeWood Pond No. 2, is the second biggest, according to federal records.

The dam was declared in good shape after its latest inspection from the S.C. Department of Health and Environmental Control in 2011. The inspector asked the homeowners association to remove small trees and brush, a typical request in inspections.

Beaver Dam Lake dam was nine months overdue for its three-year inspection when the October storm hit. A DHEC spokeswoman cited limited resources and money for the inspection delay, which the agency is working to correct with a consultant and by seeking more money from the Legislature.

Owners submitted a self inspection to DHEC in February indicating the dam was in good condition.

In 2010, homeowners spent an estimated $50,000 to repair the riser, which allows residents to lower the water.

“Everyone thought it was a 30-, 40-year fix,” said Lehman, managing partner of the Nelson Mullins law firm and a board member of the Beaver Dam Lake homeowners association, which owns the dam. “We thought this was a dam in good shape.”

But the Oct. 4 storm, which brought more than a foot of rain, challenged the strength of dozens of dams in the Columbia area.

Of the 15 state-regulated dams that failed in Richland County, eight had received satisfactory inspections within the past four years, according to DHEC records.

Lehman woke up the morning of Oct. 4 and broke into tears watching television reports about heavy flooding in areas around Columbia. He said he was moved thinking about the problems others were facing and wondered how he could help.

Then Lehman went outside. The storm had started to take its toll on Beaver Dam Lake.

Yards were flooded. A creek that trickled into the lake was gushing through a6-foot-wide channel. A 3-foot geyser of water spewed from a drain where a pipe channeled water through the dam.

“No one had any idea of how much more water was coming,” Lehman said.

After Lehman paddled in his kayak to the riser, the leaders of the Beaver Dam Lake homeowners association met. They alerted residents downstream at Silver Lake, Lehman said, though no damage was spotted on the dam.

That changed Monday morning.

Help starts arriving

Residents discovered that a sinkhole created a half-moon-shaped dent on top of the dam at Beaver Dam Road the day after the storm.

They called the Richland County Sheriff’s Office and DHEC.

“We were calling anyone we could come up with,” Lehman said.

One neighbor called landscapers who worked for the neighborhood association. The landscapers brought 10 1-ton sandbags from a brickyard, which were placed in a semicircle in front of the sinkhole later Monday.

The landscapers also dug a 2-foot channel across Beaver Dam Road near the emergency spillway to release more water in a controlled breach of the dam.

As a precaution, neighbors downstream received two rounds of calls from authorities Monday suggesting they might want to evacuate.

Hopes for a quick solution were dashed Tuesday when half of the sandbags disappeared into the sinkhole.

The water was winning.

Residents made more calls.

“We wanted to make sure the authorities knew this was a tenuous situation and that we believed we were not able to manage those risks by ourselves,” Lehman said.

Another round of reverse-911 calls went to residents downstream on Tuesday morning.

A suggestion came about calling SCE&G, which could offer more equipment.

Although the electric utility has no responsibility for the dam, the company sent a truck with a large boom arm. It placed 20 more 1-ton sandbags to keep the water from eating more of the road and the earthen dam underneath.

SCE&G also brought pipes and a pump to siphon water out of the swollen lake, a job started by city of Columbia Fire Department trucks.

S.C. National Guard troops soon arrived to help fill and carry sandbags. They also helped fill sand into large dumpster bags bought at home improvement stores.

The guard rotated about 100 troops at the dam working straight through Tuesday and Wednesday, said S.C. National Guard Lt. Col. Robert Carruthers, who was overseeing operations around Columbia.

But more help would be needed.

Nothing worked

When the last large sandbag was put into place Tuesday night, the wall collapsed. Water levels had fallen, but the lake remained swollen enough to keep pressure on the dam.

Calls to state emergency officials by residents yielded more help.

A Chester County highway contractor, United Infrastructure, showed up to bring rock. Work began on building a wall around the growing sinkhole.

By that time, experts on site included a dam expert from the U.S. Department of Homeland Security, said David Wilson, chief of DHEC's Bureau of Water. Homeland Security oversees the Federal Emergency Management Administration.

DHEC had officials on site since Monday. Agency director Catherine Heigel visited several times.

“I breathed a sigh of relief,” Lehman said after having a growing number of professionals on site. “You know they're going to be successful.”

Early Wednesday, however, the rock wall fell apart.

The water won again.

“Everything we were trying seemed to be logical,” Lehman said. “It was discouraging.”

Some residents said experts gave estimates that the dam would fail within four hours. Speculation grew about the damage that would be inflicted in heavily populated areas downstream, including Dentsville, Arcadia Lakes and Forest Acres, if the Beaver Dam Lake failed.

Wilson said the water from the 27-acre lake would have been a like a second punch to dams downstream after the rush of water that surged through creeks during the rain storm.

Another round of reverse-911 calls went out suggesting voluntary evacuations for residents downstream.

100 tons of rock

Experts, engineers and residents huddled at the dam trying to develop solutions quickly. It was an unusual situation for crews used to more methodical planning.

“Typically, you spend weeks to come up with the best approach, which we didn’t have time to do,” Wilson said.

Concerns grew about the dam.

But just as the dam was about to reach its worst, a solution was found. Crews simply took the rest of the rock and started filling the sinkhole.

Adding an estimated 100 tons of rock stopped the lake from eating through the road and earthen dam, giving residents hope that a final solution had been found. The next few days were spent securing the sinkhole.

A wall of steel sheets was added around the riser later in the week. That created a barricade, that remains in place until the homeowners can repair the dam.

With both the rock and steel barricade, “We have on belt and suspenders,” Lehman said.

The work at Beaver Dam Lake yielded hard lessons and warm moments.

Some of the techniques for filling the sinkhole rock were used to help with the breach at the Columbia Canal, Carruthers said.

And after the worst of the fears about the dam failing ebbed Wednesday, a group of children who lived downstream at Silver Lake visited the crews.

They brought cookies and bracelets to thank them for the work. Later they brought treats in bags with messages on them, including, “Thank you for saving our lives.”

That was just part of the attention crews received from neighbors, who constantly brought them food during the crisis.

“I think everyone put on 5 pounds,” Carruthers said.

Teamwork wins

Beaver Dam Lake dam and the road over it remain scarred more than a month after the storm.

The pavement is stripped away over the emergency spillway. A stripe of rock cuts the road in the middle of the dam. Large rubber tubes that helped suck water from the lake lay across the road.

Beaver Dam Lake homeowners have applied for help from FEMA to pay for materials to save the dam. Lehman said the association has committed to pay “tens of thousands” of dollars so far, but he did not provide an exact figure.

To repair the dam and reopen the road, the steel sheets and rock must be removed, Lehman said. Work also is needed on the riser and emergency spillway. Lehman had no estimate on the cost.

But the neighbors are grateful for the help they received from local and state agencies and private contractors, all of whom helped them rescue the dam.

The collaboration beat back the water.

“There was a lot of brainstorming going on,” said Eric Boomhower, an SCE&G spokesman, who was among the 20 utility officials on site. “I don’t know if it would have worked without everyone working together.”

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