The Hudson River is only as clean as its watershed. Runoff from storm events contain excess yard chemicals, oil from parking lots, and other debris that was never intended to end up in the Hudson. Since the streets in cities are non-porous, the water flows through the watershed tributaries to the Hudson Estuary, and contributes to habitat pollution.

Greenway Environmental services is dedicated to cleaning up storm water in the Hudson Watershed, and has developed an innovative method of doing so. Through a system known as biofilitration, the water on the sides of highways is filtered - toxins are removed and clean water is then transferred to its original destination. The biofiltration medium is nothing new, Greenway has put this natural process to work on the sides of highways.