On Dec. 14, 2005, a section of dam wall along the old Taum Sauk reservoir collapsed, sending 1.3 billion gallons of water rushing down the side of Proffit Mountain in rural southeastern Missouri.
The wall of water followed the Black River and swept through Johnson's Shut-ins State Park, depositing tons of rock, boulders and sediment along the way. It also damaged the park's lone residence, which housed park superintendent Jerry Toops, his wife, and their three children. They, too, were swept away, but all survived with only minor injuries.
Bill Bryan is the current director of Missouri's state park system, but in 2005 he worked for then-Attorney General Jay Nixon. They toured the flood-ravaged park below the reservoir the following day.
"We kind of bushwhacked back into the shut-ins, and saw that amidst all the devastation, the shut-ins were still intact," Bryan said. "They were filled with a lot of debris, but it was very heartening to see that what we had, in terms of a resource, was still intact, if not covered in debris and in need of a lot of TLC and clean-up, but it was still there."
"It was a very haunting place to be the day afterwards," Gov. Nixon told reporters last week. "I'm glad to see that we've gotten it back to a way that folks can visit there and swim there, and do all the fun stuff that Johnson's Shut-ins is famous for."
Ameren Missouri was fined $15 million by the federal government over the dam breach, and later agreed to a $180 million settlement to public entities, such as the park. The St. Louis-based utility tore down the remnants of the hydro-electric reservoir and built a new facility on the same mountaintop.
"We've got expansion joints, just like in a concrete highway," plant manager Dave Fitzgerald said in a 2009 interview. "There is a rubber inserted piece that will allow the dam to expand and contract, and water still will not be able to pass that barrier."
The new concrete wall contains 3.2 million cubic yards of concrete, which Ameren officials said in 2010 is almost equal to the amount of concrete used to build Hoover Dam near Las Vegas.
The rebuilt hydro-electric plant and reservoir went online in 2010. In a brief written statement, Ameren Missouri said that the $490 million facility contains "state of the art engineering" that "operates both safely and efficiently."
It also took four years to rebuild Johnson's Shut-ins, although the state allowed some sections of the park to open for weeks and months at a time, starting in 2007.
The park has been fully restored, but also has a few new features, including a "scour trail" that shows how the landscape was impacted by the reservoir collapse.
"The trail takes visitors from the valley, up the scour, essentially as far a we can go before you get into the protected area around the power plant reservoir," Bryan said. "That trail allows you to experience something that you can't see anywhere else ... (the flood) scoured away the trees, the soil, the rocks, all the way down to bedrock, and it exposed geology spanning millions of years."
Johnson's Shut-ins State Park is located near Lesterville, about 100 miles southwest of St. Louis. It's also located near Elephant Rocks State Park and near Taum Sauk Mountain, the highest point in Missouri.
The Associated Press and Linda Lockhart contributed to this report.
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