PROBLEMS FROM LAND OCCUPANCY 205 



replenished by river infiltration, the ground water will eventu- 

 ally be contaminated by the soluble chemical wastes carried in 

 the stream. 



River Control 



reservoirs 



River-basin development for flood control, storage, and navi- 

 gation has had many incidental effects upon ground-water stor- 

 age, recharge, and discharge. Some reservoirs have increased 

 the yield from underlying ground- water reservoirs, sometimes 

 at serious disadvantage to storage in the surface reservoir. The 

 McMillan Reservoir on the Pecos River in New Mexico leaks 

 rather profusely into beds of gypsum, and this water reappears 

 in the Major Johnson Springs a few miles downstream. When 

 the reservoir is full, the discharge of these springs approaches 

 250 cubic feet per second, compared with a minimum dis- 

 charge of 33 cubic feet per second when the reservoir is 

 empty. 42 The Pine View Reservoir on the Ogden River in Utah 

 overlies the Ogden Valley artesian reservoir, which is the prin- 

 cipal source of water for the city of Ogden. That city is reaping 

 the benefit of a substantial reduction in natural ground-water 

 discharge effected by Pine View Reservoir. 



Ogden Valley, Utah. iS The city of Ogden obtains all but 

 a small part of its municipal water supply of about 15 mil- 

 lion gallons a day from an artesian reservoir in Ogden Val- 

 ley, where the city is the only appropriator. The water flows 

 out by artesian pressure in the valley, which is 12 miles east 

 of the city and at an elevation high enough that the water 

 is distributed throughout the city without resort to pump- 

 ing. The artesian reservoir is filled to capacity nearly every 

 year during the spring runoff from melting snow, and proba- 



42 U.S. National Resources Committee, Regional Planning, Part 10. "Pecos 

 River Joint Investigation, Summary, Analysis and Findings," Nat. Res. Plan- 

 ning Bd., p. 59, June 12, 1942. 



« Reference: Thomas, H. E., The Ogden Valley Artesian Reservoir, Utah 

 State Engr. Tech. Pub. 2, 1945, 37 pp. 



