CITY AND INDUSTRIAL WATER SUPPLY PROBLEMS 75 



I find that it is this last, or the identification, that is the most difficult 

 for people to understand. A summer seldom passes when I do not have 

 a call or letter from some individual who asks if I can give him a couple 

 of hours so he can learn to recognize the algae that may be in the water 

 supply for which he is responsible. Although I feel that these requests 

 may constitute a part of the Algologist's work, especially if he is a member 

 of an educational institution, I know it cannot be done in the few hours 

 available. Such a procedure, if attempted, can only lead to inadequacy and 

 questionable results. 



Briefly, we can now summarize the answer to the first question in one 

 statement. The Algologist not only knows the names, but also some of 

 the physiological and ecological relationships, of the organisms with which 

 he works. 



Let us now proceed to the second question by assuming that the indi- 

 vidual has the necessary qualifications. The success which he will attain 

 in the solution of City or Industrial Water Supply Problems will be propor- 

 tionate to the degree of successful application of the above principles. He 

 has a choice of two procedures, either of which may lead to the solution 

 of the problem immediately at hand. One is by a complete and detailed 

 survey of the water supply involving chemical and physical analyses as 

 well as qualitative and quantitative analyses of both phyto- and zooplank- 

 ton. Here the plankton data may be extracted for immediate use at any 

 point during the survey, if such is necessary. The other data may be 

 used immediately, or they may be incorporated in the records and later 

 put to use in future studies of aquatic environments, which in turn lead 

 to a better understanding of water supplies. Such a study as this usually 

 necessitates the services of a permanent Staff Member who in reality can 

 be rated as a highly trained Limnologist. Today I do not intend to deal 

 with the problems of the professional Limnologist, but only with the occa- 

 sional and varied problems which concern the consulting Algologist. 



For those systems where such detailed and elaborate records are con- 

 sidered non-essential by those in charge, then the second procedure is ap- 

 plicable, and I presume is the most widely used. Possibly we can con- 

 sider Columbus, Ohio, as a fair example. Its water supply lies mainly in 

 the Scioto River, which is a drainage system in the west central part of 

 the State. Two reservoirs were created by Griggs Dam about four miles 

 west by northwest of the City, with a capacity of approximately 1,627,- 

 000,000 gallons, and by O'Shaughnessy Dam twelve miles north, with an 

 approximate capacity of 5,000,000,000 gallons. In both cases the dams 

 were constructed across narrow, rocky gorges, so that much of the im- 

 pounded water is in vertical walled reservoirs. This is especially true of 

 Griggs Reservoir. Because of the nature of the watershed which is almost 

 entirely farm land the water often maintains a fairly high turbidity fol- 

 lowing storms which result in severe run-off. Spring thaws also contribute 

 turbidities which may continue well beyond the middle of June. Clear 

 water, with intermittent periods of turbid water caused by rains, then 



