Hanson Formpave Permeable Pavement & Stormwater Source Control Systems

The Problem

Increasing urbanisation and rapid run-off have put a tremendous strain on conventional storm water drainage systems. This has resulted in sewers and culverts becoming overloaded during periods of heavy rain and contamination of streams and rivers.

Secondly, heavy metals, hydrocarbons, rubber dust, silts and other detritus are all deposited on impermeable surfaces during dry weather. These are scoured off such surfaces during periods of heavy rain and transported at best into expensive treatment works, or directly into rivers and streams where they cause severe environmental damage.

The Solution

Sustainable Urban Drainage Systems are increasingly being used to prevent run-off and flooding, and as a method of collecting and cleaning storm water.

The Hanson Formpave Storm Water Source Control System allows heavy rain to infiltrate through a permeable concrete block paved surface into a unique sub-base before being released in a controlled manner into sewers or water courses. Discharge rates of 2.5 litres/hectare per second are easily achieved. Alternatively if the underlying geology is suitable, the water can be infiltrated directly into the sub-grade.

The water leaving the Hanson Formpave system is cleaned by filtration and microbialaction and can be used for secondary non-potable uses such as fl ushing toilets and watering soft landscapings. A further advantage of the system is that roof water can be drained directly into the sub-base via a roddable sump, or if siphonically drained, through a dispersion chamber.