Client: NCC Conservation District
Date: February 28, 2017
VanDemark & Lynch was contacted by the residents and local representative of the Cardiff, Tarleton, Woodbine, and Woodbrook subdivisions to determine if the FEMA floodplain of the Shellpot Creek requiring over 140 homeowners to have flood insurance, some thousands of dollars per year, was accurately mapped.
It was determined that the topographic mapping was based on out of date standards and hydraulic model used to establish the base flood elevation used a hyper conservative flow rate. V&L, contracted through the New Castle County Conservation District, conducted a topographic survey of the Creek to create hydrographic and hydraulic models to delineate the floodplain to the latest mapping and modeling standards. The model and report were submitted to FEMA as a request for a Letter of Map Revision (LOMR). Of the 146 properties included in the study, 99 were completely removed from the floodplain and insurance requirement, and another 37 had their flood insurance premiums reduced.