A flood of progress
Published 12:27 pm Wednesday, April 2, 2014
A construction worker preps framing to be removed from a section of retaining wall along Mill Pond Tuesday afternoon.
Eric Johnson/photodesk@austindailyherald.com
Workers finish first part of Cedar River flood project; Parts of North Main Street to close next month
Despite a brutal winter and a spring that refuses to heat up, construction workers are making good time on flood mitigation plans along the Cedar River. The next phase of the project, which involves closing part of North Main Street, will begin next month.
Austin Public Works Director Steven Lang said North Main Flood Control workers had put in about 95 percent of the sheet pile and footing work necessary for an eventual “invisible” flood wall, a series of aluminum stop logs that can be stacked up to three feet past the high-water mark from the record 2004 flood.
“It’s good that they were able to make progress through that cold winter with the deep frost,” Lang said.
Work progresses on the retaining wall next to Mill Pond along Main Street North.
Workers had to hurry during the winter while the area’s water table was still low. They will still need to complete some sheet pile and footing work as they put in a new storm sewer.
“Now it’s just a matter of how the spring runoff affects the project,” Lang said.
Lang said workers will begin on a storm water pumping station near the northwest corner of the Austin Municipal Pool parking lot, one of two such stations. To do that, the city will close North Main Street from First Drive to Eighth Avenue on May 1 or soon after, according to Lang.
The intersection at North Main Street and Eighth Avenue West will remain open until July 1.
The invisible wall will be about 7 feet higher than North Main Street’s current elevation.
To account for the difference, North Main Street from the Austin Municipal Pool to Eighth Avenue will be raised about two feet. The permanent wall will be constructed two feet higher than that, and the invisible wall will make up the difference.
The invisible wall’s flexibility allows the city to put in the aluminum logs whenever a major flooding event is forecast, which means the city would be prepared for floods even worse than the one Austin experienced in 2004.
North Main Street from the pool to Eight Avenue will be closed from May through October so construction crews can raise the road. If all goes well, the $14.5 million project will wrap up by July 1, 2015.
