53 



and consequently the water commissioner paid no attention to tlieir 

 diversions. On the tributaries the records of the diversions by the 

 Lirger ditches are fairly complete, but in each district there is a large 

 number of small ditches with early rights for which tliere are no 

 records, so that the measurements on these tributaries can not be 

 used in the computations of the return seepage. The flood period 

 in the South Platte and its tributaries is usually in June. At this 

 time flood water flows from these tributaries into the Platte and 

 there are no measurements at their mouths, and therefore an accu- 

 rate record of the supply in the main stream for the month of June 

 can not be secured. During the months of July and August the 

 reported diversions by the large ditches on the tributaries of the 

 Platte leave so narrow a margin for supplying the small early 

 ditches that it is fair to conclude that the entire flow of these tribu- 

 taries is diverted during those months, and whatever water reaches 

 the Platte from them is seepage water from the lands close to the 

 river. For these two months, therefore, the records of flow and 

 diversions on the South Platte will give a fair idea of the amount 

 of return seepage in the river. The records of the stream flow are 

 taken from the report of the United States (leological Survey 

 (Water Suj^ply and Irrigation Paper Xo. 99). Records have been 

 kept by the Survey at South Platte, which is above all diversions; 

 at Denver, which is on the line between districts 8 and 2 ; at Kersey, 

 which is on the line between districts 2 and 1 ; and at Julesburg, 

 Avhich is at the lower end of district 64. This divides the river into 

 three sections, one from the South Platte to Denver, which includes 

 district 8; one from Denver to Kersey, which includes district 2; 

 and one from Kersey to the State line, which includes districts 1 

 and 01. In the tables which follow the measurement at the upper 

 station of each section gives the supply for the ditches within the 

 section. The difference between the stream flow at the uj^per sta- 

 tion and the sum of the diversions and the flow at the lower station 

 represents the gain or loss in the section. The results of these com- 

 putations are shown in the following tables. The first table gives 

 the results for Jul)^ and the second for August, 1903. These tables 

 are based upon the supposition that none of the natural flow of the 

 tributaries reaches the main stream. Measurements of the flow and 

 diversions of these tributaries are complete enough to show that 

 this is a fair assumption. 



