METHODS FOE PREVENTING BAD EFFECTS DUE TO ALGuE. 13 



PENNSYLVANIA Continued. 



The growth affected the taste of the water on boiling, but was not regarded as 

 dangerous to health. 



A very fishy taste and smell. I have been unable to locate, but had an idea it 

 came from vegetation. 



The water during the autumn is so foul in taste and odor that it was necessary 

 to shut off the supply. The odor is similar to that of decayed fish. 



The first season of using reservoir the water became so fishy that it was almost 

 unfit for use. Since that, owing to our care of reservoir, we have had no trouble 

 whatever. 

 TEXAS: 



At this time of the year algae are fierce; some days we are on top and some 

 days the algae are on top. Costs us an average of $25 a month for cleaning out 

 algae from two reservoirs. 

 WISCONSIN: 



Universal complaint, caused by the odor and taste due to algae. 



METHODS IN USE FOB PREVENTING BAD EFFECTS DTTE TO ALG-ffi. 



In order to prevent the odors and tastes above described,' engineers 

 and those in charge of water supplies have tried various remedies, 

 none of which has been perfectly satisfactory. Since few of the 

 algae can develop without sunlight, the most frequent recommenda- 

 tion has been to cover the reservoir, and this method has proved suc- 

 cessful in a few instances. However, the expense involved is so great 

 as to make the remedy prohibitive in most cases, and other methods 

 have had to be resorted to. One precaution which is now almost uni- 

 versally recommended as a means of preventing the growth of algae is 

 to remove all the organic matter possible from the reservoir and to keep 

 the source of supply as free as can be from dead and decaying animal 

 and vegetable matter. In one notable instance millions of dollars 

 have been spent in the removal of earth and the substitution of gravel 

 at the bottom of an immense new reservoir. It remains to be seen, 

 however, whether this will be sufficient to insure permanent freedom 

 from these troublesome plants. It is certain that attempts of this 

 kind will delay the appearance of algae in quantity, and, wherever it 

 is possible to do so, every effort should be made not only to clean up 

 the reservoir at the time of its construction, but to keep it as free as 

 possible from organic matter after it is filled. In addition to cleanli- 

 ness a direct pumping system with duplicate, in case of breakdown or 

 repairs, has often been recommended for use with ground water, 

 which usually produces a more luxuriant growth of algae and similar 

 organisms than surface water. Where it has been necessary to store 

 such water, it has been advisable to limit the capacity of the reservoir, 

 and frequently this storage is only intended to be used in case of fire. 

 Even so, the cleansing of the reservoir and the frequent flushing of 

 the water mains has been considered necessaiy. In storing surface 1 

 water subdividing the reservoir is occasional^ resorted to, and means 



