In deciding how best to confront flooding or water quality problems, localities often employ a mix of two types of infrastructure. Traditional gray infrastructure involves human-engineered facilities such as detention basins and underground pipes that centrally capture and convey stormwater to a local waterbody. Green infrastructure (GI) is a decentralized approach that relies on natural land, working landscapes, pervious pavement, and buffer strips to absorb or capture rainfall where it falls, recharging the groundwater aquifer, reducing stormwater runoff and the pollutants and sediment that accompany it or storing it for later re-use.  

Many communities have begun to add green infrastructure components to traditional gray solutions. Green infrastructure is often the most cost-effective way to manage stormwater from regular rain events, as most systems can be designed to easily capture the first inch of rainfall. Gray infrastructure is almost always needed to manage precipitation from larger storms. 

With the right design, GI practices can be applied in almost any setting, including urbanized areas where stormwater controls can be integrated into existing features. The repair of roadways, parking lots, and sidewalks, as well as the upgrading of sewer systems, present opportunities to consider GI alternatives, including Green Streets. 

For more information on green streets, see here.