The EPA will use run-off reducing pavement and install water-cleansing rain gardens to find strategies to filter pollutants out of rainwater before it joins the water supply.
According to the EPA, runoff from parking lots and driveways is a significant source of water pollution, especially in cities where there is so much of it. Rain carries any number of pollutants — leaking motor oil, hydrocarbons from exhaust, leftover fertilizer — from pavements to the watershed (that’s where we get the water we drink).
Permeable pavement and absorbent plants have been offered as ideas for making parking lots greener, but no real-world tests have been conducted to determine if these methods will actually reduce pollutant runoff. The EPA will build more of these parking lots and study them over the next 10 years using three different types of porous pavement along with rain gardens.