Other shafts can be used, e.g. for access for inspections or high-pressure flushing of ditches. A regulator drain shaft is needed for rainwater retention systems.
The permeability of the soil is key to the efficiency and therefore the size of the infiltration system. A lot of attention should therefore be paid to establishing the type of subsoil present.
The geotextile protects the infiltration system from the penetration of dirt and roots.
Infiltration ditch body
The ditch holds the rainwater, which can infiltrate the soil from the ditch. GRAF ditches are suitable for HGV loading up to SLW 60. There are therefore virtually no restrictions on how the ground above them is used.
The incoming water displaces the air in the infiltration system. This may escape via the ventilation.
A shaft filter is fitted upstream to prevent the infiltration system from being contaminated. GRAF provides numerous shaft and filter systems for very different requirements.