(Above) A construction worker’s view of the Riverwalk site west of Dearborn Street on May 17. The area outlined by the brown steel wall, which has been pounded into the riverbed, is where the new Riverwalk will be poured. It will also extend under the bridge. (Photo provided by Chicago Department of Transportation. Click on image to view larger version.)

May 23, 2014 – Workers building the Chicago Riverwalk will get Memorial Day off but then continue pounding steel beams into the riverbed longer than expected. However, the installation of the steel that will form the river wall – from State Street three blocks west to LaSalle Street – should wrap this week as predicted last week by the Chicago Department of Transportation.

In his weekly report to neighbors of the Riverwalk, the project’s construction manager, Oswaldo Chaves, says additional “H piles” still need to be installed between Clark and LaSalle Streets.

Also next week, the first caisson, 75 feet long and six feet in diameter, will be drilled just east of the Clark Street Bridge.

“The steel casing will be vibrated down to the required elevation,” explains Chaves. “The caisson rig will then drill out the soil from the interior of the casing to the required bearing elevation. Once the caisson is at the required elevation a full-length steel rebar-reinforcing cage will be placed inside the casing. Then the caisson will be filled with concrete.”

CDOT had expected to begin drilling the first caisson last week but divers found too much debris at the bottom of the river. The debris has since been removed.

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