improved residential property
As used in this subchapter, “improved residential property” means a single-family year-round dwelling, the construction of which began before March 1, 1975 , and which serves as the owner’s permanent place of abode at the time of its acquisition by the United States, together with not more than three acres of land on which the dwelling and appurtenant buildings are located that the Secretary finds is reasonably necessary for the owner’s continued use and occupancy of the dwelling: Provided, That the Secretary may exclude from improved residential property any waters and adjoining land that the Secretary deems is necessary for public access to such waters.