62 CONSERVATION OF GROUND WATER 



Cruz Valley in Arizona (see page 38), the ground water is con- 

 sidered to be fully appropriated, and new wells are drilled only 

 as replacements to wells covered by established rights. 



Roswell Basin, N. Mex. 18 About 120,000 acres of land is ir- 

 rigated in the Roswell Basin of the Pecos Valley, almost 

 entirely from wells. The first artesian well was drilled into 

 the limestone aquifer in 1891, and the great development 

 of large flowing wells for irrigation began about 1903. Ar- 

 tesian pressures dropped markedly during the next decade, 

 and new development was practically stopped by 1915. By 

 1925 the area in which artesian flows could be obtained had 

 shrunk from the original 660 to 425 square miles, and many 

 farms in the outskirts of the valley had been abandoned. 



The New Mexico ground- water law, first passed in 1927 

 and then modified in 1931 to meet objections of unconstitu- 

 tionality of minor features, was intended primarily to pro- 

 tect the water resources of this basin from exhaustion, al- 

 though the regulatory procedures are applicable to all 

 ground-water reservoirs in the state. The statute gives the 

 state engineer authority to safeguard the basin's water sup- 

 plies against overdevelopment and waste. In the past two 

 decades waste from wells has been practically eliminated, 

 and no new water rights have been granted for additional 

 development of the artesian basin. In recent years the with- 

 drawal by wells from that basin has been of the order of 

 210,000 acre-feet a year. Partly because of control measures, 

 but undoubtedly with considerable assistance from excep- 

 tionally heavy precipitation in 1941, the average annual 

 artesian pressures in wells were generally higher in the 



is References: Fiedler, A. G., and S. S. Nye, Geology and Ground-water Re- 

 sources of the Roswell Artesian Basin, N. Mex., U.S. Geol. 

 Survey Water Supply Paper 639, 1933, 372 pp. 



Morgan, A. M., Geology and Shallow-water Resources of the 

 Roswell Artesian Basin, N. Mex., A r . Mex. State Eng. \2th- 

 13th Bienn. Rept., pp. 155-249, 1938. 



Bliss, J. H., Ground-water Problems of New Mexico, Assoc. 

 Western State Engr. Proc. 21, pp. 55-58, 1948. 



