Faced with the threat of severe flooding, Delaware City wanted to protect its residences and businesses near its historic waterfront. Delaware City selected Duffield Associates to design a flood barrier along the Delaware River at historic Battery Park to protect against the 100-year flood. To fund the project, Duffield Associates assisted Delaware City in obtaining grant money from the Federal Emergency Management Agency for the cost of constructing a flood retaining wall.

An early concept design included a decorative cast concrete flood barrier that would have raised the existing park wall as much as 2 feet in some areas. At early public involvement meetings, area business owners were concerned that the higher wall could obstruct water views.

Working with City and Federal officials, Duffield Associates proposed an innovative solution that would not only provide the needed flood protection but would also allow views of the Delaware River. The design included a lower flood wall with removable fiberglass panels that could be installed during the threat of flooding so that residents would be protected but, during normal conditions, could be removed thus retaining the open waterfront feel.

This system of removable flood panels, supported by an aesthetic mix of steel posts and railing and strategically placed concrete parapets, was designed to withstand the hydrostatic and hydrodynamic forces caused by a 100-year flood. The panels are constructed of Fiber Reinforced Plastic (FRP) weighing less then 75 pounds each, allowing them to be easily and rapidly installed during flood threats. The panels are designed to slide into place between steel posts which are anchored to the top of an existing concrete cap. Under normal conditions, the flood panels are removed and stored.

This win-win solution which employs an innovative material in a non-traditional use protects this historic community and its economy while preserving the aesthetics of its historic waterfront.

Our participation in this project won the Grand Conceptor Award from the Delaware Council of Engineering Companies.