Concentrations of magnesium, calcium, 

 chlorides, total alkalinity, and total hardness, 

 and values of pH and conductivity generally 

 varied inversely with the flow. They were 

 lowest during spring runoff and heavy rains, 

 and highest during low flow in late summer 

 and the colder periods of winter. Exceptions 

 were the Ahnapee and Pensaukee Rivers, 

 tributaries to Lake Michigan, where calcium, 

 total alkalinity, total hardness, and conduc- 

 tivity decreased from late spring and summer 

 to lowest values in August and September when 

 flows were stable or slowly receding. 



Chlorides varied more in tributaries to 

 Lake Superior than in tributaries to Lake 

 Michigan. In the Lake Superior tributaries, 

 chlorides ranged from 0.0 to 540.0 p. p.m., 

 usually 0.5 to 5.0 p. p.m. The extremely high 

 value of 540.0 p. p.m. was recorded in the 

 Marengo River, a major tributary of the Bad 

 River, on February 10, 1964, when the flow 

 was low. During more usual flows, chloride 

 concentrations there were 1.0 to 1.5 p.p.nn. 

 Other tributaries of the Bad River did not 

 have high chloride concentrations. A high 

 chloride value of 6.0 p. p.m. also was found at 

 one station on the Bad River below the con- 

 fluence of the Marengo River on February 10, 

 1964. 



High concentrations of chloride also were 

 recorded in Scales Creek (287.0 p. p.m.), a 

 tributary of the Traprock River, and Hill 

 Creek (55.0 p. p.m.) of the Lake Superior 

 drainage. The high chloride values in these 

 streams did not appear during low flow. The two 

 creeks, which drain opposite sides of the same 

 ridge, nnay be affected by copper mining in 

 the area. 



Concentrations of chlorides were higher 

 than usual on a few streams in Ontonagon and 

 Gogebic Counties of the Lake Superior drainage 

 in late winter during periods of low flow. 

 Magnesium, calcium, total hardness, and con- 

 ductivity values also were high when the 

 chloride content was high. 



The range for chlorides was 0.7 to 25.0 

 p. p.m., usually 1.0 to 14.0 p.p.m. in Lake 

 Michigan tributaries. The high value of 25.0 

 p.p.m. was obtained at one station on the 

 Rapid River. The water at this station was 

 affected by discharge of waste from a nnilk- 

 processing plant located upstream. Above this 

 plant the chloride concentration was lower . 



Nitrites were found at a few stations. 



All streams were alkaline with the excep- 

 tion of Five Mile Creek (pH 6.9), Mud Lake 

 Inlet (pH 6.8), Mud Lake Outlet (pH 6.8), and 

 Rice Lake Outlet (pH 6.9), tributaries to Lake 

 Superior, and the upper portion of Werners 

 Creek (pH 6.7), a tributary to the Whitefish 

 River that flows into Lake Michigan. These 

 streams are small and have flows less than 

 1.0 m.3/sec. (35 c.f.s.). 



The pH was lowest during the spring run- 

 off when streams that normally are alkaline 



may become acid for short periods. The pH 

 slowly rose to a peak in August or September. 

 With the onset of winter, the pH fell until 

 spring. The pH may be high when flows are 

 extremely low in late winter. 



Phenolphthalein alkalinity was seldom found 

 in Lake Superior tributaries. It was detected 

 when flows were low in late winter and late 

 summer in Seven Mile Creek and Rock, Falls, 

 Otter, Pilgrim, and Marengo Rivers. 



Ahnapee and Pensaukee Rivers of Lake 

 Michigan had phenolphthalein alkalinity from 

 April to November, and it was present in some 

 samples from the Ford River, Days River, 

 and Marblehead Creek. 



Temperature records for many of the 

 streams discussed in this report are available 

 from the Bureau of Commercial Fisheries 

 Biological Station at Marquette, Mich., for 

 dates other than those shown on the tables. 



CAUSES OF CHANGES IN 

 WATER QUALITY 



Water quality of the streams changed 

 throughout a year and from year to year. The 

 values of the various measurements varied 

 with the flow, temperature, and season of the 

 year. 



The quality of stream water was influenced 

 by various natural and manmade causes. 

 Natural factors that affected the water quality 

 in a given area were flow of the stream, 

 elevation of the water table, turbulence, shade 

 from vegetation, and variable influences of 

 tributary streams. The water quality also 

 was influenced by the physical and chemical 

 characteristics of the ground topography of 

 the stream bed and drainage. Man affected 

 the water quality through industrial wastes, 

 domestic sewage, changes in land use, and 

 impoundments of water behind dams. 



LITERATURE CITED 



AMERICAN PUBLIC HEALTH ASSOCIATION. 



1960. Standard methods for the examina- 

 tion of water and wastewater. 11th ed. 

 American Public Health Association, 

 626 pp. 



APPLEGATE, VERNON C, JOHN H. HOWELL, 

 JAMES W. MOFFETT, B.G. H. JOHNSON, 

 and MANNING A. SMITH. 



1961. Use of 3-trifluormethyl-4-nitrophenol 

 as a selective sea lamprey larvicide. 

 Great Lakes Fish. Comm., Tech. Rep. 

 1, 35 pp. 



BROWN, C. J. D. 



1944. Michigan streanns- -their lengths, 

 distribution and drainage areas. Mich. 

 Dep. Conserv., Inst. Fish. Res., Misc. 

 Publ. 1, 21 pp. 



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