Oldcastle Infrastructure Written

Written

Course Information
The intent of green infrastructure (GI) is to mimic the natural water cycle during a stormwater event. Traditionally, when a site is developed, most runoff is directed toward a downstream drainage system and carried offsite. An undeveloped site allows infiltration and evapotranspiration, with some overland flow and runoff during heavy storms.

Green infrastructure provides decentralized Best Management Practices (BMPs) for treating stormwater by infiltrating it into the subsoil to reduce volume and flow, and doing so in smaller systems located throughout the site to treat water closer to the source.

Stormwater is filtered through vegetation and soil to reduce the impact of stormwater on the drainage system and downstream receiving waters. Stormwater can also be stored for re-use in applications such as irrigation.

More areas throughout the United States are increasingly turning to the use of green infrastructure in stormwater-mitigation projects—both new and retrofits—favoring it for its environmental and ancillary benefits.

Green infrastructure helps address the demands that ongoing development places on stormwater infrastructure against the backdrop of increased impact from flooding events from more frequent and intense storms, with resulting runoff from impervious surfaces.

Such weather events create flooding risks and potential for water pollution. It’s a driving factor in the D grade the American Society of Civil Engineers gave U.S. stormwater infrastructure in its 2021 Infrastructure Report Card.

Author
Mark Sweeney, Product Manager, Stormwater, Oldcastle Infrastructure

Learning Objectives
By the conclusion of this article, the reader should be able to understand the following:

• What constitutes green infrastructure (GI) in New Jersey and how it works in stormwater mitigation.

• In which circumstances do regulations such as the New Jersey Administrative Code 7:8 require green infrastructure.

• The significance of green infrastructure and where it works best.

• How to design for green infrastructure projects to obtain successful outcomes.

• The role of manufactured systems in designing stormwater mitigation projects.