The Use of Reservoirs 321 



After the walls have been raised to the proper height, the 

 bottom of the reservoir is plowed, harrowed fine, and the whole 

 flooded with water, if practicable, to better fit the soil for 

 puddling. In case the soil is at first too open for flooding all 

 at once, the water may be led in furrows close together, filling 

 as many at a time as the capacity of the pump will permit, 

 turning the water into others when a sufficient saturation has 

 been reached. When the bottom of the reservoir has been 

 thoroughly puddled over the whole area and continuous with the 

 puddled bottom and sides of the walls, there will usually be but 

 little loss from seepage. 



The sluice for taking out water for irrigation should be laid 

 in the wall at the level of the ditch outside which carries the 

 water to the fields or garden, but at some distance above the 

 bottom inside, so that the water may not be entirely withdrawn 

 and permit the sun to dry the soil, thus destroying the effect of 

 puddling. In cold climates, it is also important to retain enough 

 water in the reservoir to prevent the bottom from freezing, as 

 this may destroy the effect of puddling. 



The sluice should project entirely through the walls on both 

 sides, and be provided with a suitable gate or valve for closing 

 and opening it, either fully or only in part, according to the 

 amount of water needed, and the dimensions should be such as to 

 permit more water to be taken out than is likely to be needed. 



The most thoroughly satisfactory and permanent outlet for 

 a reservoir can be provided by using wrought iron pipe of suit- 

 able size, provided with an elbow at the inside, which opens 

 upward. This may be closed by means of a plug worked by a 

 T lever or handle, keeping the threads well protected with 

 cylinder or wagon grease, to prevent rusting in. 



Oftener the sluice is made of 2-inch plank, tightly put 

 together and provided with a gate, as represented in Fig. 75*. 

 In other cases, the mouth of the sluice is cut off obliquely, and 

 a gate is hinged to the upper side and provided with a handle 

 reaching above water, to which a cord is attached for opening 



"From Bulletin No. 55, Kansas Agr. Exp. Station. 

 U 



