Comparison of the two stations on the four dates for which comparable 

 'data are available shows that the station in the river had, on the average, 

 more chloride and free and albuminoid ammonia than the station in the lake. 

 This finding is entirely consistent with expectation because the river is 

 contaminated by sewage. Nitrite was the same at both stations, and nitrate 

 was nearly the same, although we should expect the river station to have more 

 of both forms of nitrogen. The mean values of nitrogen for these stations 

 are not strongly indicative of pollution. Compared with the mean for stations 

 in the Island Section (Table 23), only albuminoid ammonia was notably high, 

 while nitrite and nitrate were decidedly lower. Compared with the polluted 

 waters reported by Mason, all forms of nitrogen except albuminoid anmonia were 

 low. It may be concluded that the water of the river and of the lake nearby 

 is not heavily contaminated by sewage. Yet the rather high results for albu- 

 minoid ammonia point toward pollution in some degree. The question arises, 

 why are the other forms of nitrogen so lou - in the case of nitrite and nitrate 

 much lower than in the Island Section? Consideration of this question will be 

 deferred until similar results for the Maumee Bay Section have been presented. 



I The Ohio State Board of Health (1902) made a study of the water at the 

 ' ?ort Clinton intake, which w/is some distance west of Station 1$9. One sample 

 was taken in each of the months of April, June, July, and August, I9OI. The 

 results obtained showed great variation. Chloride ranged from 12.9 to 1U7.7 

 parts per million^ nitrite from a trace to 0.030j and nitrate from a trace to 

 1.58. Free and albuminoid ammonia were less variable with means of 0.0l(6 and 

 0.l81i part per million, respectively. Because of the wide variations, and the 

 difference in position of the stations, it probably would be unprofitable to 

 attempt to draw conclusions from a comarison of these data with those obtained 

 in 1930. The high chloride of the earlier ?amoles was believed to result from 

 the use of salt in the fishing industry at Port Clinton. 



Conclusions Regarding Pollution 



The data on oxygen and nitrogen obtained in 1930 lead to conclusions 

 similar to those reached for the Island Section. Nitrogen determinations 

 indicate light pollution of the water of the river and the lake near its 

 mouth, but apparently the added demand upon dissolved oxygen has not been 

 great. In view of the small discharge of the river and low intensity of 

 pollution. Portage River may be regarded as of little importance in con- 

 tributing polluted water to the lake. 



Maumee Bay Section 

 Oxygen, carbon dioxide, and hydrogen-ion concentration 



Season of 1928 



In 1928, samples were taken at three stations in the vicinity of Maumee 



93 



