projects within the National Conservation Area established under and consistent with this title. (p) Off-Highway vehicles (1) In general Except in cases in which off-highway vehicles are needed for administrative purposes, including project construction and maintenance, or to respond to an emergency, the use of off-highway vehicles shall be permitted only on designated routes within the National Conservation Area designated by this title. (2) Designated routes (A) In general The Secretary of the Interior shall manage existing designated routes in a manner that— (i) is consistent with off-highway vehicle and mechanized use of the designated routes under existing laws and regulations established one day prior to enactment of this Act