Pervious or porous pavement are a unique and effective means to address important environmental issues and support green, sustainable growth. By capturing stormwater and allowing it to seep into the ground, porous pavements are instrumental in recharging groundwater, reducing stormwater runoff, and meeting U.S. Environmental Protection Agency (EPA) stormwater regulations. This pavement technology creates more efficient land use by eliminating the need for retention ponds, swales, and other stormwater management devices. In doing so, pervious pavements have the ability to lower overall project costs on a first-cost basis.
Advantages of Pervious Pavements
- Water treatment by pollutant removal.
- Less need for curbing and storm sewers.
- Improved road safety because of better skid resistance.
- Recharge to local aquifers.
There are two types of porous pavement: porous asphalt and pervious concrete. Porous asphalt pavement consists of an open-graded coarse aggregate, bonded together by asphalt cement, with sufficient interconnected voids to make it highly permeable to water. Pervious concrete consists of specially formulated mixtures of Portland cement, uniform, open-graded coarse aggregate, and water. Pervious concrete has enough void space to allow rapid percolation of liquids through the pavement. The porous pavement surface is typically placed over a highly permeable layer of open-graded gravel and crushed stone. The void spaces in the aggregate layers act as a storage reservoir for runoff. A filter fabric is placed beneath the gravel and stone layers to screen out fine soil particles. Another variation to the concrete pavement is the use of open celled concrete pavers which provide a durable driving surface and material to plant vegetation which further helps eliminate pollutants.
Popularity: 51% [?]
Not that I’m either for or against this currently… but seeing that our highway engineering and construction technology is already decades behind Europe, why would we purposely invite capillary erosion and tempt frost heaving directly underneath our already poorly made roads? Other than that, I’m all for returning local water to the local water table.