Maintenance of pervious surfaces

Factors that influence the maintenance requirements of pervious surfaces and impact on the design criteria include:

Type of use (maintenance will need to be increased as public use increases and as litter/debris increases).
If the surface is open to the public or is it private?
The level of trafficking (both volume of traffic, axle loads and vehicle speeds).
The local environment (for example is the area established or are building works being conducted locally?).
The proximity and nature of landscaping and gardens (for example will there be loose soil/plant debris from gardening activities or seasonal leaf fall?).
Long-term ownership and responsibility for the surface.
Will the owner/users undertake the necessary maintenance and should they be advised to do so?

Maintenance includes vacuum-cleaning using commercially available sweeping machines and ensuring site owners are given a clear checklist of the monitoring and maintenance requirements. The effects of maintenance (or lack of it) on infiltration rates is discussed together with the likely frequency of sweeping.

Materials removed from the voids or the layers below the surface may contain heavy metals and hydrocarbons (as is the case with asphalt surfacing) and need to be disposed as a controlled waste. This is no more onerous than the disposal of gulley pot or interceptor sediments.

Other methods of maintenance include lifting and relaying blocks where they become completely blocked. However, this rehabilitation is rare unless there has been a serious deposition of sediments.