At a Glance

By implementing its first bioretention retrofit, a county school system improves water quality, enhances educational opportunities, and sets the stage for future LID retrofits.

Project Description

Biohabitats performed low impact development (LID) assessment and design for bioretention retrofits at Hickory and Forest Hill Elementary Schools. These projects were the first bioretention retrofits completed for the Harford County Public Schools and serve as a model for future efforts in the school system. The retrofit designs provide on-site water quality treatment while considering educational value and safety issues. They also contribute to the County’s pollutant loading reduction goals and watershed restoration objectives.

Biohabitats began by assessing LID retrofit opportunities to treat impervious areas of both schools. After the sites for final design were selected, Biohabitats performed hydrologic and hydraulic analysis, developed construction plans, and produced an engineer’s cost estimate for a bioretention cell retrofit in an existing parking lot island at Forest Hill Elementary School.

This project provided water quality treatment and safe conveyance of runoff from 0.3 acres of previously untreated parking lot. Biohabitats also developed inspection and maintenance guidance for the overall project and produced planting plans for all three retrofit designs. Providing a unique outreach component to this project, Biohabitats staff visited fourth graders at Forest Hill and taught them about the importance of native plants and the benefits of bioretention.

Once constructed, the retrofit was celebrated with a dedication ceremony attended by students, faculty, County staff and officials, and Biohabitats staff.

The project received a 2011 Top Stormwater and Erosion Control Project award by Storm Water Solutions Magazine.



Chesapeake/Delaware Bays

Physiographic Province




Expertise Areas

Ecological Restoration, Infrastructure, Urban Ecology, Water


Harford County Department of Public Works-Division of Highways and Water Resources


Harford County, Maryland, United States