Pollution retention and biodegradation within pervious pavements

Pervious paving systems (meant to mean permeable pavements within this context and used interchangeably) have been demonstrated to effectively and efficiently trap and degrade urbanderived pollutants such as hydrocarbons and metals. UK research by Formpave and Coventry University has demonstrated that 98.7 % of applied mineral oil is retained within the pavement structure over a test period of five years. Retained oils are subject to extensive biodegradation
with around 45 % of that added to a permeable pavement system degraded within six months.
The key to the success of the paving system is the geotextile membrane layer located beneath the bedding layer. The physical and chemical properties of the geotextile reduce the velocity of water flow, immobilise the pollutants and provide an appropriate habitat for the growth of a microbial biofilm that degrades the oil. Pervious pavements have been installed all over the world and have been a significant contributor to the source control of pollution and to the drive for sustainable drainage systems (SUDS) in the UK.