THE IRRIGATION AGE. 



271 



suction pipe to the pump. This method is adapted to 

 secure a larger supply than the method just mentioned. 

 Three or four, or more wells can be arranged in a 

 straight line, twenty or thirty feet apart, and connected 

 to a pump placed near the center of the row of wells. 

 In the diagram (Fig. 3) will be found an arrangement 

 suitable for a battery of eight to twelve wells. These 



Fig. 4. Measuring weir at pumping plant near Garden City, Kas. 

 At the time the photograph was taken the pumping plant was yielding 

 200 gallons of water per minute. 



wells are arranged in pairs, close together, each pair 

 of wells being forty to sixty feet from the next pair 

 on the same suction line. The object of placing the 

 wells close together in pairs is for the purpose of remov- 

 ing a large amount of the fine sand from the water 

 bearing gravel. This can be done in gravels like those 

 found in the western valleys, by pumping vigorously 

 from one of the pair of wells, and at the same time run- 

 ning clear water into the neighboring well. By this 



means it should be possible to clear out all the fine 

 material between the two wells. If the water bearing 

 gravels are of the kind usually found in the river valleys 

 of the western prairies, a pumping plant can be con- 

 structed sufficiently large to supply from 2,500 to 3,500 

 gallons of water per minute without lowering the water 

 more than ten feet. Pummng plants of greater ca- 

 pacity than this will usually not be profitable. A large 

 number of moderate sized plants is more desirable than 

 a few large oues. 



KIND OF PUMP. 



Probably the most satisfactory pump for use in 

 irrigation is the centrifugal pump. However, there are 

 many kinds of small centrifugal pumps. It does not 

 pay to purchase any but the very best machinery for 

 the pumping of water, as poorly designed machinery 

 soon proves too expensive. The various kinds of pumps 

 differ greatly in this respect. The centrifugal pump 

 used by the irrigator should be of the enclosed runner 

 type, provided with self-oiling bearings of the oil ring 

 type. There are several excellent makes of centrifugal 

 pumps on the market, and any of them will do good 

 work if the size and design of the pump fit the condi- 

 tions under which it must work. The maker of the 

 pump should have full information of all the conditions 

 under which the pump is to be installed. These condi- 

 tions should include the distance that the pump must 

 discharge the water above its outlet; also the amount 

 of suction or the distance the water must be lifted below 

 the pump inlet. The following points are important to 

 those about to install pumping plants: 



1 The efficiency of the centrifugal pump under 

 actual working conditions is higher for the large size 

 pumps than for the small size. Pumps having less 

 than three-inch diameter discharge pipe will show a low 

 efficiency. 



2 A centrifugal pump will work better and be 

 more efficient if the suction pipe is as short as possible, 

 relative to the length of the discharge pipe. On this 



ACCESSION NO. 8003 



SUGGESTED ARRANGEMENT OF WELLS AND PUMP FOR A PUMPING PLANT 

 DESIGNED TO RECOVER 2500 GALLONS OF WATER PER MINUTE 



Fig. 3. Suggested arrangement of wells and pump for a pumping central concrete pump house and a group of twelve wells arranged along 



plant designed to recover 2,500 gallons of water per minute. In places the suction pipe leading to the pump. The suction pipe should be placed 



where the gravels are deep and unusually coarse, the wells at the end underground as near to the level of the ground water as practicable, 

 of the line of suction pipe may be omitted. The plant consists of a 



