Gorham Road Stormwater Retrofits
The existing paved and concrete medians along Gorham Road (between the intersections of Maine Mall Road and Western Avenue) were removed and new treatment areas were established. The retrofitted medians include eight vegetated stormwater treatment systems; seven landscaped areas with trees, shrubs, and perennials; and six tree lined sections ranging from 100 to 200 feet in length with three to seven trees per section.
The systems treat approximately one acre of impervious area and resulted in the removal of one acre of impervious cover. The stormwater treatment systems are modified linear gravel wetlands that provide treatment by forcing polluted stormwater through a treatment media and gravel layer and an aerobic zone that is always wet. This results in the best removal efficiency of nutrients and metals.