Efforts to dredge toxic industrial chemicals from the Fox River will also mean the removal of five sunken vessels.
Press-Gazette Media reports the wrecks were no surprise to J.F. Brennan Co. Inc., hired by area paper companies to clean polychlorinated biphenyls from the river.
They are behind Tetra Tech. Company spokesman Richard Feeney says they are tugboats and barges either intentionally sunk or allowed to sink decades ago after they couldn't be used anymore.
Since they can't be left there, the plan is to photograph the more recognizable pieces, compile existing photographs and information about the early days of the area's shipping industry and construct a display at the Neville Public Museum.
Brennan will complete most of this season's dredging soon and then start bringing up the wrecks.