478 TiiiRTY-FiRST Annual Report 



$10,000 was specified for more general investigations in the three 

 valleys of the county. 



All water supplies, including the artesian waters, have their 

 origin in the rainfall and run-off, and since no run-oft' measurements 

 had been made in the San Simon Valley, the first effort was di- 

 rected toward studying the run-off, both in the trough of the valley 

 and at the mouths of the mountain canyons. Gaging stations were 

 installed on the San Simon Creek at San Simon and above the 

 Cienega, and at the mouths of Cave, East Turkey, and Wood 

 canyons. 



Four reservoir, sites have been surveyed, three in the trough 

 of the valley and one in Round Valley. The Round Valley site li 

 situated between Cave and East Turkey creeks and at such an 

 elevation that water from both creeks can be diverted into it. 



The artesian area which extends nearly to Bowie on the west 

 and for ten miles southeasterly from San Simon has been developed 

 extensively already. It has been studied tl^e past year to deter- 

 mine the possibilities of further development. The yields of wells 

 ctnd the artesian pressures have been measured and studied in their 

 relation to the depths and types of construction. Cross-section^ 

 and piezometric lines have been drawn to determine the source and 

 movement of the artesian waters. Influences of various factors, 

 such as shutting oft" the flow in winter, are under investigation. 



The possibilities of development of groundwater by i)umping 

 are being studied. 



Owing to the great extent of arable land as compared with the 

 water supply, a soil survey has l^een made of an extensive area 

 reaching from Bowie to Portal. The survey was made coopera- 

 tively by this Department and the U. S. Bureau of S.oils. 



A site for the State experimental artesian well was selected, 

 but owing to the high prices prevailing for well casing and well 

 drilling, it has been impossible to contract the drilling of the well 

 for a sum within the limit of the appropriation. 

 SAN PEDRO VALLEY 



A cooperative agreement has been made with the U. S. Geo- 

 logical Survey for a joint study and publication of the geology and 

 water resources of the San Pedro A/"alley. Dr. Kirk Bryan of the 

 Geological Survey has been assigned to the Valley. 



Gaging stations are being maintained at Hereford and Fair- 

 bank for the special purpose of determining the water supply 

 available at the proposed Charleston reservoir site. Silt samples, 

 also, are taken at intervals. 



