The Chicago River; from alligators to engineering On Tuesday Aug 24, 2010 Fox Chicago News reported that boaters saw an alligator in the north branch of the Chicago River in the Avondale neighborhood. It was about 3 ft long with ?? inch teeth but didn't seem to pose an immediate threat to nearby ducks. A smaller 21/2 ft alligator was found in the same area just 2 weeks earlier. Stefan Wohl, a bus driver for the Dave Matthews Band, admitted to emptying his bus' septic tank over the Chicago River while crossing the Kinzie Street Bridge. Nearly 100 passengers who were unfortunate enough to be on an architectural boat tour the afternoon of August 8, 2004 were drenched with 800 pounds of human waste. The passengers were given a refund. The driver received a $10,000 fine, probation and community service. The Dave Matthews Band donated $50,000 to both the Chicago Park District and Friends of the Chicago River. On April 13, 1992 a small stress fracture turned into a massive flood when a pile driven into the Chicago River bed near the Kinzie Street Bridge punctured the wall of a long abandoned (and possibly mismapped) 47 mile long system of coal and freight tunnels. Eventually, a hole about 20 feet wide let water, fish and muck travel into sewers and basements of several central business district buildings. Electric power and natural gas service were knocked out. Trade was suspended at the Chicago Mercantile Exchange and Chicago Board of Trade. Subway trains were rerouted. Some businesses were closed for several weeks. Workers used rocks, cement and even old mattresses to plug the hole. Damages were estimated at $1.95 billion. The disaster was classified a leak because a flood would not have been covered by insurance. In 1889 the State of Illinois passed legislation enabling the 'Civil Engineering Monument of the Millennium.' This public works project permanently reversed the flow of the Chicago River away from Lake Michigan. The Chicago Sanitary and Ship Canal, operational in 1900, along with the North Shore Channel and Cal-Sag Channel, completed in 1922 as well as locks and dredging projects were required to complete the task of carrying sewage and industrial pollution away from Chicago's supply of drinking water. During the 1990's serious efforts to clean the river became part of Mayor Richard Daley's city beautification program. Despite minor set backs, efforts to make the river clean enough for fishing, boating and even swimming continue.