Water Source Control

If there is one issue preventing the general acceptance of permeable pavements and it’s adoption, it is the perception that these pavements require extensive and expensive maintenance on a regular basis, to ensure they continue to function correctly.

This is a misconception grounded in the findings of some of the monitoring of very early attempts at forming pavements with porous blocks, and pavements with permeable blocks, which had very limited initial infiltration rates through the joints.

The initial infiltration rates suggested for our EnviroPerm™ rectangular block, would be in excess of 2000lit./sec/hectare, which in reality is 20+ times more than the recommended requirement.
It is accepted that the infiltration rate of a permeable pavement will decrease over time, due to the build up of detritus in the joints. Research by Dr. Sönke Borgwart has shown that, while the decrease in infiltration does take place, it stabilises to an acceptable level (10-20% initial infiltration rate). Evidence to date has shown that infiltration rates remain significantly higher than rainfall intensity and can handle both prolonged rainfall and short duration storms.

Some would consider that vacuum cleaning of the pavement may be necessary, in any case vacuuming may be used for general cleaning purposes. If this is considered, then the equipment must be adjusted to avoid removal of jointing aggregate, any aggregate remove must be replaced.

Prevention of any fine material contaminating the surface of the permeable pavement must be avoided, this is discussed in the Technical Innovations section under the heading of Landscaping.