26 THE BOOK OF FORESTRY 
Nature has been no less generous regarding our water 
supply. For over the entire country the average rainfall 
amounts to thirty inches per year, an amount which 
if evenly distributed would be entirely sufficient for our 
needs. Combining the effects of our climate which is 
most favorable to the land and water our country is 
capable of producing practically any foodstuff common 
to the temperate zone The total rainfall amounts to 
215,000,000,000,000 cubie feet and is equal in bulk to 
ten Mississippi rivers. 
The uses which water serves are countless. Plant 
and animal life could not do without it and these values 
of course are taken for granted. The part water plays 
in irrigation projects, in furnishing power, In filling 
streams and canals to provide cheap transportation are 
some of the other uses which water serves Of the water 
which is now flowing idly to the sea, an authority states 
that were it put upon the arid land we possess it would 
yield foodstuffs to feed 50,000,000 people. The Re- 
clamation Service has brought large tracts of land 
formerly arid to a productive state and although alto- 
gether only 14,000,000 acres out of the 40,000,000 acres 
in the country at large which can be irrigated are 
“ander the ditch” the work is proceeding steadily. The 
land capable of irrigation when supplied with water 
will support 20,000,000 people on account of its great 
fertility. Our total water supply is ample. It is merely 
a question of getting it to the land which needs it. 
While water is a splendid servant it is a bad master. 
The damage done each year by erosion (two hundred 
square miles of fertile land is laid desolate each year) 
and floods is enormous. The annual damage inflicted 
by floods is now in the neighborhood of one-quarter 
billion dollars, five times as much as it was ten years 
