THE JOINT CONSERVATION CONGRESS 



93 



IN THE absence of Hon. Theodore Soils, to read the report of that Section. 



E. Burton, chairman of the Section The Section of Waters was the Inland 



of Waters, the chair called upon Dr. Waterways Commission, and the report 



V J McGee, secretary of the Inland was one of the most interesting of the 



Vaterways Commission and erosion entire Conference. The address is 



xpert in the United States Bureau of given below. 



ADDRESS OF DR, W J McGEE 



I/I R. CHAIRMAN, and gentlemen of the 

 Y| Conference, I shall do no more than ask 

 attention to a few primary ideas with 

 espect to our waters. 



In the first place, I would like to empha- 

 ize, and have you all join me in emphasizing 

 lie great fundamental fact that our water is a 

 esource. Hitherto it has not been our cus- 

 Dm to regard water as a resource of a defi- 

 itely limited quantity. We have been accus- 

 3med, after the manner of the ancients, to 

 link of the four elements, of which water is 

 ne. We have been accustomed to think of 

 : as free and abundant as the air or the light 

 f the sun, or the amplitude of the earth. The 

 rimary idea which we are desirous of im- 

 ressing is this, that there is just so much 

 rater and no more. In this connection it is 

 ecessary also, as we conceive it, and as I 

 ope you will all agree, to apply the quanti- 

 itive method of dealing with water, the same 

 lethod which we employ in dealing with coal 

 r iron ore, or any other resource. That, in- 

 eed, is requisite to the forming of a clear 

 lea concerning water as a resource water 

 f which there is only a certain amount and 

 o more. The application of the quantitative 

 lethod is absolutely essential. 



In the report of the National Conservation 

 lommissipn, which you heard read yesterday, 

 le quantity of water and the sources of the 

 rater with which we are blessed were set 

 orth in considerable detail. I shall not 

 rouble to repeat the figures, but merely to 

 ender clear the primary idea of water as a 

 esource, and I am referring, of course, to 

 icsh water. Let us have it in our minds that 

 hie sole source is the rain which descends 

 rom the heavens. That boon, after reaching 

 hie earth, is divided, and half of it is re-evap- 

 rated, and a portion of this half may be re- 

 recipitated as rain. We need not follow that 

 alf further than to say that after reaching 

 he surface of the globe, it is again evapo- 

 ated. One-third of the entire amount flows 

 own to the sea through the rivers, of which 

 lany are navigable. One-third of the total 

 mount let us have this clear in mind flows 

 own to the sea. There remains one-sixth, 

 nd that is consumed or absorbed. On one- 

 ixth, in the last analysis, depends the habit- 

 bility and productivity of our country, of 

 very acre of our farm land and of every 

 ere of our forest land. Its productivity is 

 ependent on this remaining fraction of water. 

 Jor do we often realize how large a quantity 

 f water is consumed in plant growth and in 



animal existence. We do not often realize 

 that each average adult man of one hundred 

 and fifty pounds takes into his system in the 

 course of each year no less than one ton of 

 water. We do not realize that on the aver- 

 age each bushel of corn requires in the mak- 

 ing something like fifteen or twenty tons of 

 water. This is an illustration of the funda- 

 mental importance of water to the produc- 

 tivity of our land. 



Now to return for one moment to the 

 quantity of water which we receive from the 

 heavens. It is rainfall, and an average of 

 thirty inches of rainfall all over the entire 

 length arid breadth of the land means a quan- 

 tity equivalent to ten Mississippi Rivers, and 

 that is all we have. Without it, no acre of 

 our land would be habitable. Without it, no 

 industries, of course, could exist, and without 

 that one-sixth of it which is consumed and 

 absorbed in vital processes, the land would 

 be unproductive and stale and not fit to form 

 the home of mankind. 



The effective fraction of the water descend- 

 ing from the clouds is not that which flows 

 off over the surface during storms ; on the 

 contrary, it is that which seeps into the earth 

 in such fashion as to form ground water. Let 

 us have clearly in mind this idea of ground 

 water as a part of the great resources made 

 up of the total quantity of water. How much 

 ground water have we? Of late, we have 

 been considering the matter with some care, 

 and we estimate that within the first one hun- 

 dred feet of the surface there is an accumula- 

 tion of a body of water, which ought to be 

 permanent, but which is not quite, equivalent 

 to a reservoir sixteen or seventeen feet in 

 depth, spreading over the three million square 

 miles of the surface of our land. That sub- 

 surface reservoir is the value on which we 

 must depend for agricultural production, forest 

 maintenance, and for the development and 

 continuation of all our industries. That sub- 

 surface reservoir of ground water, equivalent 

 to a layer of water spreading over all our 

 surface sixteen or seventeen feet in thickness, 

 is the supply upon which we must depend. 



When you speak of that vast reservoir 

 spreading over our land from the Atlantic 

 to the Pacific and from the lakes on the North 

 to the gulf on the South ; when you think of 

 that as the sole source of supply for agricul- 

 ture and all other activities ; when you think 

 of it as the sole source of all our streams, 

 which we are feeding slowly from seepage 

 through the ground in the springs or other- 



