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Formpave home

Aquaflow® Water Harvesting

Over the past 15 years the 'Hanson Formpave's Aquaflow' system has become the Flagship design for permeable paving. The unique sub-base cleans pollutants from run-off, creating a safe, PH neutral water for storage and re-use within the sub-base. Water can be captured from all impermeable areas; roofs, paths and driveways. It can be further stored in a tank and then pumped out for all exterior uses; gardens and car washing. Because cars are washed on the driveway and the driveway is permeable, even this water is recycled.

The Aquaflow Water Harvesting system collects water from all impermeable surfaces, roofs, paths and especially the driveway. All water falling onto the paved surface is cleaned by the Inbitex geotextile layer before storage. Recommended uses for this water are garden watering and car washing; these uses can reduce by up to 50% the household requirements for mains water. The system involves linking the roofs and paths through the Aquaflow permeable pavement (the drive) and into the voided sub-base. The rainfall (run-off) is stored within this 'reservoir' area with all surplus being discharged into a sump. The sump contains a pump which will allow the harvested water to be dispensed via a tap and hose-pipe. Rainwater tanks should be sized to provide a continuous supply between rainfalls, typically 12-20 days. Because there is no mains water attachment the harvested water can be used where there are hose pipe restrictions as the tank is treated as a subterranean water butt. Car washing becomes an environmentally friendly pursuit as the majority of the water used will automatically be cleaned and recycled as it passes through the permeable paving on the driveway. The capacity of the system is dependant on the size of driveway, but additional storage can be achieved by increasing the pump chamber (sump) size. It will be necessary to calculate the approximate quantities of water required set against the estimated quantity of rainfall. This can be done using average rainfall figures.

To use the Hanson Formpave Water Harvesting Calculator please click here ...