Porous (or pervious/permeable) pavements are surfaces that allow water to filter and flow through them, greatly decreasing problems associated with runoff. It is becoming more popular in construction practices.
Porous asphalt and concrete are specially engineered to have extra spaces (pores) that allow water to trickle down to a storage area (a sand and gravel sub-base) beneath the surface that filters out pollutants. Porous pavers (bricks) are placed in such a manner that water flows into the crevices and filters into a storage area below.
Porous pavement can be used almost anywhere, from large parking lots to residential streets and driveways.
For more information:
- Permeable pavement in the Minnesota Stormwater Manual from the Minnesota Pollution Control Agency
- Permeable pavement from the Minnesota Department of Natural Resources
- Learn more about Pervious concrete pavement from the National Ready Mixed Concrete Association
- View the Lake Superior Duluth Streams Site Design Toolkit
Check out this video on how to install porous pavement.