POND CONSTRUCTION 



bottom area of the pond should be 

 deepened and graded to drain prop- 

 erly, and soil removed from all the 

 pond edges so that the water has a 

 minimum depth of approximately 

 2 feet. Earth taken from the edges 

 and not used in the dam may be 

 used for sloping the bottom of the 

 pond so it will drain properly. 



Earth can be properly placed on 

 the fill by keeping the fill higher 

 on the edges than in the middle. 

 If this is done, there will be no 

 tendency for equipment to spill 

 over and earth can be dumped the 

 proper distance from the edge. 

 Dirt should first be dumped about 

 2 feet from the upstream, or inside 

 toe, stakes and about 18 inches from 

 the lower, or downstream, stakes. 

 This procedure will save labor by 

 making a natural slope. Con- 

 versely, all cuts with the scraper 

 should be made deeper at the edges 

 than at the center. This prevents 

 the equipment from sliding away 

 from the banks, a possibility which 

 might result in a ragged slope. 



Fill placed on the dam should be 

 properly compacted. Maximum 

 compaction is effected by putting 

 earth in place in thin layers and 

 traveling the full length of the fill 

 each time. On high dams, special 

 compacting equipment, such as a 

 sheepsfoot roller, is needed, and the 

 required density is obtained by the 

 control of moisture content. Al- 

 though the compacting reduces the 

 amount of settling, allowance 

 should always be made for it. 



The actual process of construct- 

 ing a series of hatchery ponds is 



somewhat different from building 

 a dam, but the method of placing 

 and compacting the material is the 

 same. The slopes on the dikes be- 

 tween the ponds should be uni- 

 formly 2 to 1. Where there is a 

 series of ponds, it will be necessary 

 to make only the dams or levee on 

 the outside of the series water-tight 

 by using a clay core. All levee bases 

 should be properly prepared by 

 clearing off organic debris and plow- 

 ing the entire area. 



The design of a hatchery is de- 

 pendent on the size, shape, and 

 topography of the land on which 

 it is located. If the plot of land 

 is properly sloped, ponds may be 

 planned in such a way that suf- 

 ficient earth can be removed from 

 the pond site for the embankments. 

 Ideally, the ponds should be from 

 1/4 to 1 acre in n^ea, but the topog- 

 raphy of the land will dictate, to 

 some extent, the size of pond that 

 can be constructed most economi- 

 cally. Under no circumstances 

 should there be any large number 

 of ponds of an acre or more in size. 

 Small ponds are handled more eas- 

 ily and are generally more pro- 

 ductive (fig. 1). 



Plans for excavation and for the 

 placement of drains and waterlines 

 should be made by a competent en- 

 gineer. All elevation stakes for 

 drain and waterlines and for the 

 dikes should be placed before exca- 

 vation starts. The drainage lines 

 are generally placed in or through 

 the levees so that it is essential to 

 have these lines in place before pond 

 construction starts. The drainage 



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