The pervious concrete is one of the many ways we treat storm water at Arlington Echo. The storm water passes through the pervious concrete, to the rain garden and overflows to the bioretention area.  Every drop of storm water that we treat will help our watershed.

 Pervious concrete is a certain type of asphalt in which there are multiple layers of different sized aggregate. The different sized aggregate allows for air pockets within the asphalt to promote infiltration of rainwater into the ground.                  

Benefits- While promoting infiltration of rainwater, the pervious pavement will slow down the rushing water and reduce run-off and erosion into nearby waterways. The rainwater being infiltrated through the pavement is then directed to bio-retention areas such as shade gardens, and bogs. The main goal of the pervious pavement is to influence a natural infiltration system into the ground rather than a rapid loss of excess nutrients into waterways. 

All of these stormwater methods allow the water to seep through the ground and into the aquifer and then enter the Bay at a cool 50 degrees; instead of a running directly from hot asphalt and other impervious areas.

 Water filters through the pores in the concrete slowing down and depositing sediment and pollutants that it is carrying with it.  There are 3 layers in our pervious pavement: sand, cobble and the porous cement.