The PorousPave technology now includes Permapave
As world population increases, demand for water in many cities is quickly approaching, and in some cases already exceeds, the limits of sustainability. Providing sufficient water for the world’s rapidly growing urban population is increasingly the greatest challenge faced by governments world-wide.
Of equal importance is the capture and disposal of storm water in these cities. As cities expand, so to do the areas of pavement. Urban way of life dictates cities have paved surfaces, particularly for motor vehicle access. These paved surfaces are impervious, so each time it rains water floods across the paved areas. Vast underground systems collect storm water and carry it to an outfall point of disposal – usually a close by permanent waterway – a river, lake or ocean.
As storm water travels across paved areas to collection points, it gathers all manner of pollutants from the pavement. Pollutants such as cigarette butts, plastic bags, leaf litter etc. (gross pollutants), oil and grease residues from automobiles, toxic chemicals of all types from accidental spills and discharges, nutrients such as phosphorous and nitrogen, and coliform bacteria from human and animal wastes. Outfall waterways become quickly contaminated.
Before urbanisation, rain water percolated into the ground and collected in subterranean aquifers, filtering contaminants in the process. Today, rain water floods across paved urban environments, collects contaminants, and is discharged with the contaminants to outfall waterways. Detrimentally, this results in contamination of important water sources close to cities, reduction of water levels in subterranean aquifers, increased ground water salinity and drying out of the subgrade on which the city is built.
Annual rainfall in most of the world’s cities deposits more water than can be used by the population. It is, however, all run to waste. By running the water to waste, we contaminate many of the close by water sources which could become viable sources of urban water, and worse, we render unusable those important subterranean aquifers which could be used as valuable new urban water resources.
If pavements could be made porous and water could permeate into the sub-grade rather than be collected and sent to outfall, important new and economical urban water supply solutions are potentially available.
Dymon Porous Pave is an advanced porous pavement technology which is used to produce porous and permeable pavers, stormwater filtration grates, bio-retention systems, poured in situ pavements, sidewalk tree surrounds and stormwater harvesting systems. Replacing impervious areas with porous pavements will potentially allow stormwater to be treated and harvested for re-use, allow storm water to return to subterranean aquifers rather than discharged to outfall and strategically reduce contamination of outfall waterways.