a whirlpool was seen by the pilings on the southeast corner of the kinzie st. bridge (that was where the bridge-tender's tower was). a large construction company started to put gravel and sandbags into the hole (the hole was the size of a car). later quick-drying concrete plugged it. concrete walls were built in the tunnel on both sides of the river. on april 19, six days after the flood started, the leak was stopped. two days later the water started to be pumped out. it was pumped out slowly so no other problems happened. on may 21 the pumping was done.