Backwater Lakes (continued)

It is also important to examine the surface area dimension of backwater lakes. The diversion of Lake Michigan, which begins in 1900 and accelerates through at least 1920, and the construction of the dams at Peoria, LaGrange and Alton, lead to a dramatic increase in water levels; 2.1 meters (7 feet) are added to midsummer low flows. This increased water level deepens and extends all lakes (Table 42), merges stands of bottomland hardwood forests with river water, and kills thousands of acres of trees, mostly pin oak and pecan, which provide major food sources for waterfowl and other species. The end result enlarges the size and reduces the number of water bodies between 1903 and 1969. The La Grange Pool sees an 89% increase in surface area, and the Alton Pool experiences a 137% increase from 1903 to 1969 (Bellrose 1983).

Table 42: Surface Areas of Lakes in La Grange and Alton Pools in 1903 and 1969 (Bellrose 1983)

Scientists raise concerns about the loss of the backwater lakes and the resulting impacts to commercial fishery and waterfowl. In 1919, Stephen Forbes observes that the reclamation and drainage of the floodplain “leaves the Illinois River much as Samson was left when shorn of his locks by the self-seeking Delilah” (Havera 2002). Also in 1919, a bill is introduced in the Illinois legislature to provide $50,000 to purchase backwater lakes as fish breeding grounds. Unfortunately, Governor Frank Lowden vetoes the bill (Schneider 1998).