Ditches for pipes

Ditches for pipes

The inlet and outlet pipes may be laid on the surface or in ditches (Fig. 2.7). It is generallycheaper to lay the pipes on the surface, but it is then more important to moor them, especially in con-nection with obstructions. Pipes on the surface may, however, inhibit transport and it can therefore be necessary to lay them in ditches. If the pipe is put in a ditch, care must be taken to avoid any damage when heavy traffic passes over the ditch. Therefore the ditch must be constructed and overfilled with gravel correctly. A ditch may be constructed in the following way: a layer of compressed crushed rock or gravel is laid as a base for the pipe in the ditch; then the pipe is laid with sufficient slope (>0.05%). Fine gravel is placed around and over the pipe to create good protection; this should only be hand compressed. Afterwards the ditch is filled with ordinary ditch material until ground level is reached. It is normal to overfill slightly because after a while the material will compress to normal terrain level.

The use of ditches will also improve the farm aesthetically because there are no pipes on thesurface. Ditches also improve the possibilities for public traffic to use the area.