SPRAY IRRIGATION. 7 



feeds a stream. The right to use water from a spring originating 

 on the farmer's land probably never will* be questioned. 



The use of water for spray irrigation requires a farm pumping 

 plant. The pump should be located as near as possible to the field, 

 so as to avoid a large discharge line, and the suction pipe should be 

 made as short as possible. The vertical suction lift should be kept 

 under 25 feet. The horizontal distance between pump and water 

 should not exceed 300 feet. Where water is taken from a stream 

 or lake having high banks it may be necessary to locate the pump 

 on a made terrace within suction lift of the water, and in extreme 

 cases it may be necessary to so locate both power plant and pump. 

 Many surface supplies are surrounded by lowlands, and under such 



Fig. 2. — Pumping from stream with 2-stage centrifugal pump and gasoline engine, 

 with house removed. Note lack of sharp angles in suction and discharge pipes. 

 D, Discharge pipe ; E, expansion joint ; G, gasoline tank ; P, priming barrel ; S, suc- 

 tion pipe. 



conditions the water may be carried to a pumping plant in an open 

 ditch or large tile, permitting the pumping machinery to be located 

 nearer the field and on firm ground. Figure 2 illustrates a pumping 

 outfit located on a farmer's wharf before a house was built. Many 

 eastern streams overflow, and where it is impracticable to place the 

 pumping plant above the high-water line it is necessary to use a 

 portable outfit which can be moved quickly. This usually is accom- 

 plished by placing the pump and engine on a set of skids or, with 

 small plants, on wheels. In either case it is well to have a perma- 

 nently located solid foundation to hold the plant when in operation. 

 A quick method of connecting and disconnecting the discharge and 

 suction pipes should be provided, bolted flange or flexible hose con- 



