62 LIMNOLOGY, WATER SUPPLY AND WASTE DISPOSAL 



Chlorobrachis gracilla was a bloom of them in whiskey distillery wastes at 

 Lawrenceburg, Indiana (Lackey 1942). Cedar swamp acid waters along 

 the Atlantic coast have produced blooms of the green flagellate Gonyosto- 

 mum semen at Woods Hole, in New Jersey and near Savannah, often 

 with an accompanying huge population of Euglena polymorpha. Reser- 

 voirs in areas underlain by granitic rocks may be troubled by yellow-brown 

 flagellates, such as Uroglena, Uroglenopsis, Synura, Chlorodesmus and 

 similar forms. Flagellates of these types are common to waters whose pH 

 tends toward acidity and are almost lacking in waters which are prevail- 

 ingly hard. The pattern behind many blooms is reasonably clear, but 

 specific causes are not clear and probably causes are due to combinations 

 of conditions. An accumulation of nutrients is certainly necessary. Small 

 streams draining sparsely inhabited areas along the Columbia River had 

 as small plankton populations as have been found despite summer tem- 

 peratures and low, clear water stages. Positive evidence is found in the 

 increased plankton populations of fertilized fresh water fish ponds, as well 

 as marine experiments at Milford, Connecticut (Loosanoff and Engle 1942) ; 

 Woods Hole; and lochs in Scotland (Gross et al. 1946). 



Control of nuisance conditions has followed three general lines. In 

 the Wisconsin lakes a sewage treatment plant was put into operation and 

 control of some industrial wastes was initiated. Further control by copper 

 sulfate was used. An attempt was made to secure legislative action for 

 diversion of sewage plant effluent. Storm sewer wastes and agricultural 

 drainage were neglected. None of these schemes achieves more than par- 

 tial success. Treatment of sewage reduces the B.O.D., and by maintaining 

 oxygen and decreasing putrescible matter, changes the nature of blooms 

 from saprophytic organisms (mainly bacteria) to presumably altogether 

 holophytic ones. This probably decreases the nuisance, but leaves an 

 abundance of available N and P in food form. Copper sulfate treatment is 

 temporarily successful, but since copper accumulates in the bottom mud, 

 where it apparently destroys clams, worms and insect larvae, its long con- 

 tinued use is questionable. The same question should be raised for recently 

 developed algacides of other natures which upset biologic balance. Diver- 

 sion of sewage or sewage plant effluents from a lake to a stream merely 

 begs the question. The streams near Madison are already extremely rich 

 in plankton, and additional food might cause nuisances therein. 



Control or elimination of bloom nuisances thus far is purely tem- 

 porary. The most promising investigations would seem to aim at the 

 removal of phosphorus. Nitrogen might at times be available by fixation 

 from the atmosphere. But before phosphorus removal is attempted, further 

 studies of the amounts and mechanism of contribution from agricultural 

 drainage should be made. In some instances, as when fertilizer is spread 

 on iced-over fields, it appears the farmer is paying for fertilizer which, on 

 the first thaw or rain, at once washes into streams or lakes. The biology 

 of industrial wastes needs much more study. The wastes of tanneries have 

 a B.O.D. averaging 1200 ppm; those of milk and distillery wastes are far 



