PAPERS ON GEOGRAPHY AND GEOLOGY 171 



and that poisoning of the water that falls pure from the 

 clouds is nearly a general practice. 



Let us take the pollution of the Illinois river, a stream 

 once renowned for its beauty and charms. Through the 

 drainage canal it receives much of the sewage of Chicago, 

 and is so befouled by this that even the bottom of Lake 

 Peoria, far down the river, has its blanket of filth. The 

 main tributaries of the Illinois are the Kankakee, Des- 

 Plaines, Fox, Vermillion, Mackinaw, Sangamon, and 

 Spoon rivers and Crooked creek. The report of 1921-2 

 says: "The conditions of the sewage of the Illinois 

 river are more pronounced than ever before." 



The Fox river valley is quite thickly populated. The 

 large cities of Elgin, Aurora and Ottawa use this as a 

 sewage channel, not to mention smaller towns that find 

 it a convenient depositoiy. The discharges of twelve 

 Elgin sewers pass into the river. Elgin is, however, 

 building a sanitary sewer system. Aurora has nine sew- 

 ers connected with the channel and there are sewer out- 

 lets from various private and manufacturing plants along 

 the river, without treatment. Aurora is said now to be 

 agitating a drainage district. An effort was made by the 

 Rivers and Lakes Commission several years ago to abate 

 the nuisance but the war interfered. 



The DesPlaines river is polluted by the sewage of Joliet 

 and by its factory waste. The corrupt condition of the 

 Sangamon river is in the reports deemed a special object 

 of concern. The sewage of Springfield and Decatur 

 goes into it. The report of 1918-19 declares that Sanga- 

 mon river is greatly polluted below Decatur. Decatur 

 now has a million dollar sanitary sewer system, just com- 

 pleted, and that will take care of raw sewage and waste 

 save in times of flood. Jacksonville and Bloomington 

 empty their sewage into creeks but it finds its way into 

 the Illinois river. The Kankakee river receives the sew- 

 age of Kankakee and there are other towns along it that 

 may contribute toward fouling it. 



Both Streator and Pontiac on the Vermillion river use 

 it for sewage and waste purposes. In the State report 

 of 1920-21 special mention is made of the foul condition 

 of the river at Pontiac. Another comment is that "Dur- 



