In order to accommodate visitation to the recreation area, the Secretary shall construct such facilities as necessary to enhance and improve access, vehicle parking and related facilities, and provide river access for whitewater recreation and for other recreational activities, immediately downstream of the Summersville Dam, to the extent that such facilities are not provided pursuant to section
460ww–4 of this title and such facilities are within the boundaries of the recreation area. Such construction shall be subject to the memorandum of understanding referred to in subsection (f) of this section.