Torrential rains that flooded downtown Oklahoma City on May 31 built up enough force to blow out the 5-inch-thick concrete slab in the basement of a city office building, an engineers' report says.
Amid the destruction, colorful paintings of shields, a spear with dangling feathers and other tribal symbols have been revealed on the basement walls of the 100 Building, which is thought to be 75 to 90 years old.
Repairing the damage to the seven-story building, at 100 N Walker Ave. just south of City Hall, is expected to cost $2.1 million to $2.3 million.
Insurance will cover most of the cost, with the state and federal governments reimbursing the city for much of the rest under terms of a disaster declaration.
The Friday night storms came on the tail end of nearly two weeks of violent weather that killed nearly 50 people, including seven schoolchildren who died in an EF5 tornado in Moore.
The report by White Engineering Associates of Oklahoma City says about 4.2 inches of rain fell the evening of May 31 between 7:15 and 11:15 p.m. It says 2 inches fell in the first hour.
Downtown streets flooded and water ran under the doors of numerous buildings.
During the storm, floodwater flowed into a pit on the Arts District parking garage construction site just east of the 100 Building.