The East Guard Lock dates to the original Erie Canal and was built to control floodwaters flowing into the canal from Schoharie Creek. Because too much water was more dangerous than too little, two sets of doors in the lock could be closed during flooding to keep the creek’s swirling waters from washing away the canal banks, while under normal conditions the doors remained open to leave a clear channel between the Erie Canal and the creek. Although most structures on the original canal were removed when the Erie Canal was enlarged, the East Guard Lock remained in use throughout the 19th century as part of a feeder canal that channeled water into the Enlarged Erie, and it continued to be used for flood control into the 20th century.