CONSERVATION OF GROUND WATERS 
195 
evaporation of free moisture from the ground in grain fields may 
tentatively be taken as 0.8 ; for grass land 0.7 ; for light forests, 
brush and second growth 0.6; and for dense forests with abund- 
ant herbaceous vegetation from 0.2 to 0.4.” 
From our cities and towns in all quarters the cry is going up : 
^‘Our water supply is diminishing, our wells are going dry !” 
What does it mean? What are we going to do about it? From 
newspaper items and from official correspondence it is evident that 
everywhere the situation is becoming acute. At the present mo- 
ment at least three of the important cities of Iowa which have 
depended on deep well supplies are looking anxiously for other 
sources, namely Mason City, Fort Dodge and Waterloo. The 
heads of the wells have fallen so low that it is becoming out of 
the question to depend on them much longer. Towns with large 
shallow wells are being forced to dig more wells or use surface 
waters. Towns dependent on impounded waters are finding 
difficulty in maintaining necessary reserves. We cannot increase 
the rainfall; we cannot find a substitute for water, although 
many establishments for that purpose are insistently thrusting 
their wares upon our notice. We must then adopt the only re- 
maining recourse — conservation. The writer recalls listening 
while a graduate student at the State University to a paper on 
the water supply of Buda-Pesth, Hungary, in which the speaker 
said that that system furnished two gallons a day per inhabitant. 
The head of the engineering department of the University in 
commenting on the paper stated that the consumption in Iowa 
City was eighty gallons per capita. The daily average consump- 
tion for Des Moines is eighty-one to eighty-five gallons per per- 
son. Does this point a moral or adorn a tale? In the flowing 
well district of the artesian basin wells are left flowing from 
year end to year end. We of central Iowa are suffering for 
this wastefulness. 
The way in which agriculture may help in conservation has 
already been discussed. In addition our forests are an important 
factor. It is a proven fact that nothing aids more in the retention 
and stabilizing of ground moisture than do the forests. In addi- 
tion to all their other attractive features they rank as one of the 
great conservers of our water reserves. This they do by checking 
the run-off, by lessening evaporation, by preventing soil wastage 
with all its attendant evils. They not only stabilize the stream 
flow, maintaining it when the run-off fails; they increase the 
supply of ground water and yield it when it is most sorely 
