Competing against the clock, greater than 1,200 guys worked in continual changes, driving massive interlocking steel pilings deep into the river's base with heavy steam hammers, nervously looking for the river to increase. In the springtime, the circulation of the river can occasionally rise drastically, as snowmelt and also rain would instantly turn the already muscular waterway right into a raving gush. The cofferdams needed to be constructed quickly during low water months. If not finished in time, the spring runoff would certainly tear them to pieces. When the work with the west side was complete, one more collection of cofferdams would certainly prolong out from the east side of the river, diverting the circulation over the just recently finished foundation.
On March 23rd, 1935, only 90 days after they started, employees finished the west side cofferdam. That springtime the river peaked at 32 feet above its normal height.