Page 245 - Moving the Earth_ The Workbook of Excavation
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DITCHING AND DEWATERING
DITCHING AND DEWATERING 5.47
FIGURE 5.35 Intercepting drain.
FIGURE 5.36 Depth and spacing of drainage tile.
a subsoil plow, as in Fig. 5.38. The plow is set to penetrate to the desired depth, and the mole is
dragged through the ground. It pushes the soil aside and compacts it. Under favorable conditions
these tubes will stay open for 5 years or more, and may open permanent channels. In other condi-
tions, they may close immediately or within a few months.
Drainage is usually to a stream, ditch, or hole. The mole is dropped in this and pulled straight
into the bank and lifted out at the upper end of the run.
A tile or metal pipe, screened with coarse mesh wire, should be placed in the outlet to protect
it against erosion and plugging by entrance of small animals.
