1919] EXPERIMENT STATION RECOED. 785 



RURAL ENGINEERING. 



Ground water in the San Pacinto and Temecula Basins, Cal., G. A. Waring 

 (U. S. Geol. Svrvci/, Water-Supply Paper 429 (1919), pp. 113, pis. Iff, figs. 15).— 

 This paper was prepared in cooperation with the State of California. 



The San Jacinto Basin is an area of 1,000 square miles in southern Cali- 

 fornia, the topography of which is diverse. The ground water of the basin 

 " is derived wholly from the rain and snow that fall on its surface. . . . The 

 ground water is stored almost entirely in the deposits of sand and gravel 

 that underlie the valleys. In some places the lowlands are bordered by partly 

 consolidated sediments v.iiich yield small quantities of water, but the under- 

 lying granitic and other crystalline rocks contain very little water, oven for 

 the supply of domestic wells." 



The Temecula Basin is drained in its western part by Murrieta Creek and 

 in the east by Temecula River. " Throughout the lowland of Murrieta Valley 

 the ground-water level is within 20 ft. of the surface, and beneath the greater 

 part the depth to water is less than 10 ft. . . . The sampled well waters from 

 Murrieta Valley range in quality from fair to good for domestic uses and for 

 irrigation. ... In the lowland along Murrieta Creek for two or three miles 

 above Temecula, the ground-water level is within 6 or 8 ft. of the surface, and 

 the continual evaporation from this moist area has caused the concentration 

 of alkali. Chemical examination of the waters tested indicates that in most 

 of them sodium is the predominant base. . . . Throughout the lowland of 

 Temecula Valley proper ground water is found within 20 ft. of the surface, 

 and in the wide sandy flats of its upper portion is less than 10 ft. below the 

 surface. ... In the minor valleys in the upper part of the Temecula Basin, 

 water is generally found relatively near the surface in the alluvial and residual 

 materials." Analyses of samples of water from a shallow and a flnvdng v/ell 

 in the area and from Temecula River showed that " the waters from both 

 wells are suitable for domestic use, but the river water is only fair because 

 of its rather high total solids and its hardness. It is also classed as fair for 

 irrigation." 



Pumping tests made at six irrigation plants in San Jacinto Valley by Herman 

 Stabler are also reported, together with a description of each plant. Data on 

 the total cost per acre of pumping water for a season of 200 days of 12 hours 

 with duty of water at .3 acre-feet per acre show that the cost per acre that 

 can reasonably be expected in the irrigation of alfalfa with distillate at 10 

 cts. per gallon is $9.64. " By continuous operation throughout the irrigating 

 season the cost could be still further reduced to $7.56 per acre with distillate at 

 10 cts. a gallon." 



Influence of forests on water power supply, A. A. Griffin (Jour. Elec- 

 tricity, 42 (1919), No. 6, pp. 268-270, figs. 5). — Studies of snow melting on the 

 Tumalo area in central Oregon, the Wind River area in southern Washington, 

 and the Yakima area in central Washington are reported. 



It was found that drifting of snow by the wind was of comparatively small 

 importance. It was also found that the retardation of snow melting in forests 

 is five to eight days in general and may be several weeks, and that in the 

 forest the snow tends to be deepest and last longest in the small openings of 

 the denser forests. " This tendency was especially noted on the Wind River 

 area and may partly account for the late melting of the snow in the small open 

 areas characteristic of the Tumalo area. In large openings the protecting in- 

 fluence from the forest would be dissipated and melting consequently more rapid. 

 An mmsual factor in delaying the melting within the Douglas fir type of forest 



