In 1926, the National Aeronautic Association proposed filling in all or part of Kingman Lake to expand Kingman Island so that a new city airport could be built there. Two years later, the piers supporting the Benning Bridge were reconfigured to permit a dredge to pass between them. The existing piers (which were apart) were replaced with piers apart. The reconfiguration was exceptionally complex, as 92 percent of the city's electrical supply passed through cables carried by Benning Bridge. The new, large dredging ship "Benning" was used to dredge the upper part of the Anacostia River, and some of the fill from this operation was used to create two new islands in Kingman Lake, named Island No. 3 ( in size) and Island No. 4 ( in size).