COLUMBIA, S.C. — U.S. Army officials knew for 36 years a dam at a South Carolina military base might not stand up to a big storm before it was breached in a massive 2015 downpour that caused a flood that killed two people and caused millions of dollars of damage, according to military records.
The same documents show repairs made before the deadly October 2015 floods likely increased the chances the earthen dam on Semmes Lake at Fort Jackson might break, according to the U.S. Army Corps of Engineers records obtained by The State newspaper.
Federal engineers inspected the dam in 2013, finding that concrete buffers blocked some water from a spillway designed to prevent water from coming over the top of the dam and weakening it. They also found holes in the dam and overgrown vegetation, which could weaken the structure, according to the documents, which included an April 2016 technical review by the Corps of Engineers.
A 1979 report found the dam's spillway could not release enough water in an emergency to save the dam and those concerns were never addressed, according to the records.
Other documents that could show any repairs the Army made to the dam are being blocked from release by the military. The newspaper is fighting in court to have that information released along with depositions between two Army officers over the flood and an August 2016 review of the storm and flooding.
Media attorney Jay Bender said the records are part of a lawsuit and should be public.
"It's our government defending a suit by citizens about the failure of the government to act properly with respect to that dam," Bender said. "We need to know who is right.'
Another problem detailed in the records came as forecasters warned for days before the 2015 flood that unprecedented amounts of rain could fall and urged dam owners to lower lake levels. But the Semmes Lake dam had broken and corroded equipment which didn't allow the water level in the lake to be drawn down, according to the records.
The Army and Corps of Engineers did not answer questions from the newspaper.
"Had they asked for federal funding for maintenance and repair after these issues were identified? Those are the kinds of questions the report raises that are unaddressed," said Lisa Jones, a Columbia flood consultant helping with lawsuits over the 2015 floods.
Several other dams also failed in the floods many in chain reactions as the water behind a broken dam surged downstream toward another dam. Nineteen people were killed.