158 CONSERVATION OF GROUND WATER 



The Arkansas River Compact of 1949 has ended a 50-year 

 interstate controversy by providing an acceptable method 

 of apportioning the river flow between water users in Colo- 

 rado and Kansas. Basically this compact provides protection 

 to water users in western Kansas. Colorado users have the 

 natural advantage of "high-ority," which would give them 

 all the water if there were no legal restraint, and in central 

 Kansas the precipitation and stream flow are great enough 

 to make it unnecessary to rely upon water originating in 

 Colorado. 



The compact provides for a division of the natural river 

 flow into the John Martin reservoir (near Lamar, Col.) and 

 of the water stored in the 420,000-acre-foot conservation 

 pool of that reservoir: 60 per cent is allocated to Colorado 

 users and 40 per cent to Kansas users. In years when stream 

 flow exceeds the demands of water users in both states, the 

 John Martin reservoir can carry over some storage to the 

 following year; in 1948 the holdover storage was of the order 

 of 150,000 acre-feet. Otherwise the compact provides for 

 division of the natural flow of the river, with short-term 

 maximums and minimums leveled off as far as possible by 

 the reservoir, and with no allowance or accumulation of 

 credits or debits for or against either state. 



Each year there are extended periods when the entire flow 

 of the river is used for irrigation above Garden City, Kans., 

 and because of return flow from irrigated lands, some water 

 is used more than once. But in most years substantial quan- 

 tities of water flow past Garden City at some season. In the 

 past decade the annual runoff at Garden City has ranged 

 from 1,340 acre-feet in 1940 to 1,220,000 acre- feet in 1942, 

 and since the John Martin reservoir was completed, the run- 

 off at Garden City has ranged from 39,400 to 306,500 acre- 

 feet. 



Although in the present stage of development the quan- 

 tity of water utilized must vary considerably from year to 

 year, the water users are not entirely at the mercy of the 



