SEEPAGE OR RETURN WATERS FROM IRRIGATION. 
59 
tion, for instance, the association becomes responsible for all dam¬ 
ages from this cause. 
§ 58. “ I am inclined to think that the seepage is much 
“ greater and of more importance in Colorado than anywhere in 
“ California, for, while I know that such percolation does exist in 
11 various places in the irrigated districts, I cannot recall a single 
“ place where it takes place in any such volume as in your country. 
“ The Santa Ana river is affected by seepage from Riverside and 
“San Bernardino valley, so that the volume of supply for the 
“ Anaheim and Orange canals below is rather increasing than 
“ diminishing, but the extent of this return is conjectural, j" 
“Some years ago the people owning water rights along the 
“ lower parts of our mountain streams imagined that the use of the 
“ water by parties located some distance above them would seriously 
“interfere with their water rights and prove very injurious to the 
“land below. Experience has proved that this tear was groundless 
“ to a large extent. Indeed, it is now found that a large use ot water 
“ in the early summer on the upper lands insures a more plentiful 
“ supply in late summer for the lower lands.” % 
Hon. Geo. P. Marsh, for a long time our minister to Italy, m 
The Earth as Modified by Human Action, in commenting on the 
results of Vigan (§ 59) states that it is generally estimated that from 
one-third to one-half of the water applied to the fields is absorbed 
by the earth, and this, with deduction of the amount evaporated, 
absorbed by vegetation, and entering into new organic compounds, 
returns to the streams or descends to greater depths. In Colorado a 
much smaller proportion of the water applied runs off and a much 
larger proportion is absorbed, as the system of wet meadows, or 
marcite and rice irrigation, does not prevail in Colorado. The 
measurements on the Poudre indicate that at least 30 pei cent, of 
the water taken from the river returns through the seepage. If 
water is applied as freely until the seepage from the outer lands 
reaches the river* * the amount of return waters will be greater than 
this amount. 
OTHER INVESTIGATIONS. 
§59. The phenomenon of return waters has been apparently 
but little noticed and less written upon. It was the subject of an 
investigation by the government engineers of France some thirty 
years ago in the valley of the Tet* in southeastern France, where 
the question became important, as it is in some places in Colorado 
in the dispute between water users of the lower valleys and those ot 
| Manuscript letter from J. D. Schuyler, Consulting Engineer, Los 
Angeles,^Cahfor manuS cript letter from President Geo. Q. Cannon, of 
Utah. , 0 ~. 
* Vigan, Annales des Ponts et Chaussees, loo /. 
