Drain location
The drain itself can be disturbed in many ways or have obstructions that hinder drainage. The location is a very important factor in this. Almost all drains are installed with the aid of a laser beam at the desired level and any desired slope. During the construction, the drain may be installed under insufficient ‘voltage’. This means that the soil is not tight at that moment. The ribbed drain that comes from the roll wants to start ‘squirming’ again. These twists can occur both horizontally and vertically in the tube direction. The chance of such squiggles is greatest when using a drain made of p.v.c. Drains made of polyethylene (p.e.) or polypropylene (p.p.) hardly have this problem.
A bad location can also be the result of poor operation of the drainage machine. The construction of the machine can also be such that it is difficult to install the drain at the desired depth. The soil type and the structure of the oil can also play a role. In peat soil, for example, the sandy substrate can occur at varying depths. The drains are then placed alternately in the sand or the peat. During construction, the resistance that the drainage machine encounters from the soil varies greatly. Depending on the type of machine, the machine can therefore show a strong tendency to go up and down. This will have to be corrected by the laser control.
The reaction speed can vary greatly from machine to machine. It is, therefore, necessary to not drive too fast under certain circumstances. On clay soil, the depth control can be greatly influenced by the presence of soft clay or sand in the subsoil. This also influences the resistance encountered by the drainage body of the machine.
The ground level is often very uneven before drains are built. Certainly, when a graded plot is drained, extreme control of the machine and the laser equipment is desirable.
The cases mentioned so far mainly relate to the trenchless installation of the drains. When using a chain digger, the varying strength of the subsoil has a more limited influence on the position of the drain. When digging the trench, however, it must be prevented that soil rolls back into the trench before the drain is placed on the bottom. This also creates a less desirable location.