Ill] FAUNA OF BIG VERMILION RIVER— BAKER 13 



of from half a mile to a mile an hour. The water was very low when these 

 measurements were taken by the State Water Survey. In its course of 90 

 miles to the Wabash River, the Big Vermilion River falls about 320 feet or 

 ZV2 feet per mile. It thus has a greater fall than either the Kankakee, 

 which is 300 miles long and has a fall of 250 feet, or less than a foot per mile, 

 or the Maumee River, which has a length of 150 miles and a fall of 154 feet, 

 or about a foot per mile (Clark and Wilson, 1912). 



The water in the normal parts of the stream is usually clear at depths of 

 one to two and a half feet, especially on the riffles. This condition was 

 noted in Salt Fork east of Sidney, and in the Middle Fork. Above Sidney, 

 except where the water is very shallow, the stream is murky and laden with 

 fine silt. During times of high water the stream is in this condition in all 

 parts of the Big Vermilion. The upper part of Salt Fork, from Urbana to a 

 point six or eight miles down stream is always more or less brownish in 

 color from the large amount of sewage, equalling as much as a third of the 

 total volume, and putrient matter as well as an oily scum is usually to be 

 seen on the surface. The shore of the stream is rendered very unsightly by 

 the mass of filth that is despoiled above the usual level by high water. At 

 St. Joseph, ten miles from Urbana, much the same condition is found. 



The upper part of the Salt Fork has been greatly modified by ditching 

 and dredging. North of Urbana for the distance of a mile and a quarter 

 above Crystal Lake Park a large ditch carries the surface drainage in a 

 straight line to the park thus cutting off the tortuous windings of the 

 original stream bed, which have been left as long, narrow, shallow ponds, 

 reminding one of the 'ox-bows' so common in the valley of the Mississippi 

 River. The bed of this ditch is about six feet below the general level of 

 the surface. For several miles above this ditch the original stream has been 

 deepened by dredging and the bed is now pretty generally five or six feet 

 lower than that of the original stream. 



From Crystal Lake Park, Urbana, to a point near St. Joseph, the stream 

 has been ditched to straighten the bed, leaving numerous 'cut-offs' of the 

 old stream bed. This canal permits a better flow of water for the disposal 

 of the sewage. Where not ditched the stream bed has been deepened. 

 The ditching has greatly modified the original stream bed, providing a new 

 and different kind of environment for the mussels and other aquatic life. 

 It is probable that all of the old fauna was exterminated during the ditching 

 operations and the sewage pollution provides an unfavorable environment, 

 which the aquatic bottom life does not seem able or inclined to enter. The 

 effect of sewage pollution may be seen all the way down the stream from the 

 source of contamination. At St. Joseph, where the stream bed has not been 

 modified, conditions are very bad, the mud in the bottom being filled with 

 gas forming bacteria which are constantly causing bubbles of gas to break 

 at the surface of the water. Were it not for the sewage pollution, the stream 



