CITY AND INDUSTRIAL WATER SUPPLY PROBLEMS 77 



numbers of organisms. In general the first is of greater importance. Know- 

 ing that only certain genera are real trouble makers, the algologist watches 

 for them especially. If one should happen to appear, he is on his guard 

 and when the next samples come in his attention is directed to it. If the 

 number of individuals of this organism is great when first seen, then con- 

 trol may be essential immediately. One variation of the rule is for Synura. 

 If one colony appears in the collections, then treat and treat fast. It may 

 be that no organisms of especial significance appear, but that the com- 

 bined total of all organisms rises steadily and rapidly. Here one must 

 use his judgment as to the best procedure; in other words, he must be able 

 to predict the probability of a "bloom." As there is a definite correlation 

 between "water blooms" and environmental conditions the quality of one's 

 predictions depends largely upon the understanding and interpretation of 

 the environment. In the case postulated above if the weather continues 

 to be warm with bright sunshine and little wind, I would recommend treat- 

 ment. Only because of these regular collections of algae and with a 

 knowledge of the probable effects of environment, can one anticipate plank- 

 ton trouble and prevent it. At Columbus we have seldom found it neces- 

 sary to apply copper more than twice during any summer since 1942. 



The preceding discussion illustrates what is probably the best known, 

 if not the most important, part played by the algologist. His position is 

 somewhat that of a "watch-dog." He anticipates trouble and recommends 

 precautionary measures before the troubles reach serious proportions. 



Along with these regular surveys, the algologist sometimes can be of 

 assistance in settling disputes that may arise in connection with water plant 

 operation or policy. An example of this occurred in Columbus where some 

 wanted to use Griggs Reservoir as a power boat course. The City was 

 to build and rent docks to accommodate these boats. Although it pro- 

 vided an additional recreation area to the City Park System, as well as 

 some additional income, a few individuals felt that maybe boats should 

 not be in the water supply. My opinion was that these boats might be 

 beneficial in the dispersion of algal blooms. Subsequent surveys tend to 

 show that this heavy, and may we say somewhat wild boat traffic, has done 

 much to disperse algal concentrations during the critical July and August 

 days. 



Another case occurred in which suddenly and for no apparent reason 

 the water entering the mains had a violent odor and flavor. A quick 

 check at the Reservoir disproved the possibility that it was of algal origin, 

 and turned the investigation to the river between the Reservoir and the 

 pumping plant. It was soon discovered that run-off from a new black 

 top pavement was the cause. 



Let us now assume that everything possible has been done and that 

 water of as near perfect quality as can be reasonably expected has entered 

 the mains. As a reward one would expect that they could sit back and 

 accept the plaudits of the community. Through my contacts with Mr. 

 Hoover and the Columbus Water Department, I find that this is not always 



