Chicago River Control Works

The Chicago River Control Works constructed in 1939 by The Sanitary District of Chicago (Ill.) prevent the polluted Chicago River from entering Lake Michigan. They consist of walls making a watertight enclosure around the river mouth, a navigation lock to pass shipping, and two sets of control gates to regulate the quantity of water admitted into the·river from the lake (see Fig. 1). The westerly or river end of the lock is approximately 1,700 ft east of the Outer Drive Bridge, which crosses the Chicago River at its mouth. The longitudinal axis of the lock extends from east to west, in line with the river. The south wall of the lock is extended 700 ft easterly of the east lock gate, to serve as a guide wall and breakwater. From the northwest corner of the lock a north basin wall runs north, connecting with an existing United States North Pier which in turn connects with the shore. In this wall are four control gates. From the southwest corner of the lock a guide wall extends westerly and slightly southerly, connecting with the northerly end of the United States breakwater. This breakwater extends due south, and from a point 1,600 ft south of its connection with the guide wall, a south basin wall was constructed to the west, connecting this breakwater with the shore. Four other control gates are in this south basin wall. The two basin walls, the lock, and the southwesterly guide wall, in conjunction with the original United States breakwater and North Pier, enclose an inner harbor basin about 1,700 ft by 2,000 ft.