The consent of Congress is given to the States of Maryland and West Virginia and the Commonwealths of Virginia and Pennsylvania and the District of Columbia to enter into the compact to create a Potomac Valley Conservancy District and to establish an Interstate Commission on the Potomac River Basin: Provided, That nothing contained in such compact shall be construed as impairing or in any manner affecting any right or jurisdiction of the United States in and over the region which forms the subject of this compact.