Holly Hill Harbor Wetland Stormwater Best Management Practices

The project was identified for environmental retrofits due to the frequent high bacteria levels that were found in weekly bacteria samples conducted just outside of the property. These elevated levels highlighted the need to prevent polluted stormwater from entering the river.

To achieve this stormwater treatment Biohabitats, an ecological design firm, was hired to identify methods to capture the runoff.  A series of in-line wetlands were designed to capture and treat stormwater while continuing to allow the functionality of the park and adequate upland drainage. The newly created wetlands will contain a sand/ wood chip mix that will allow infiltration into the soil media and absorption by plant material. This underground storage will allow a greater volume of water to be captured during storm events and slowly seep into the surrounding soils. The wetlands will be planted with hardy and attractive native wetland plants as well as those that attract pollinators. This project is meant to be a demonstration project for surrounding neighborhoods that also have high water tables and need methods to convey the water off the land while treating it before it enters the Rhode River.