DRAINAGE INDICATIONS 



six years ago. Figure 90 shows a 

 profile section through the center of 

 the pond bed. 



258. Shallow ponds resting on other 

 than muck beds. The nature of the 

 soil comprising the bed of the pond 

 is not so material as whether there is 

 sufficient natural fall to a water course 

 or to an open ditch. Where the con- 

 dition of fall and outlet are correct, 

 the pond can usually be drained. 



259. Shallow ponds not having 

 sufficient fall or natural outlet. - 

 Shallow ponds sometimes occur both 

 upon muck beds and upon clay or 

 loam beds, where conditions do not 

 permit tile drainage. There may not 

 be sufficient fall ; the distance over 

 which the drain must extend and the 

 depth of digging required may be too 

 great. In either case there remains 

 the possibility of draining by well. 

 (See paragraph 202.) A very inter- 

 esting case of this kind is reported in 

 Water Supply Paper 258, United 

 States Geological Survey. 



260. Low flat areas whose surfaces 

 lie only slightly above that of an ad- 

 jacent stream or lake, which cannot 

 be lowered by drainage. In 1894 

 the Wisconsin Experiment Station 

 undertook an interesting experiment 

 in draining a 10-acre area of muck 



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