The Wild & Scenic Rivers Act requires that detailed boundaries portrayed on maps be established and submitted to Congress within one year of designation. Agencies may finalize boundaries through their respective land management planning process.
Pending the establishment of detailed river boundaries, the Wild & Scenic Rivers Act specifies that the interim boundary is one-quarter mile on each side of the river as measured from the ordinary high water mark.
Section 3(b) of the Wild & Scenic Rivers Act states:
The agency charged with the administration of each component of the national wild and scenic rivers system . . . shall, within one year from the date of designation of such component . . . (except where a different date is provided . . .), establish detailed boundaries (which boundaries shall include an average of not more than 320 acres of land per mile measured from the ordinary high water mark on both sides of the river); and determine which of the classes outlined in Section 2(b) best fit the river or its various segments. Notice of the availability of the boundaries and classification, and of subsequent boundary amendments shall be published in the Federal Register and shall not become effective until ninety days after they have been forwarded to the President of the Senate and the Speaker of the House of Representatives.
Section 3(c) of the Wild & Scenic Rivers Act requires maps of all boundaries and descriptions of the classifications of designated river segments, as well as any subsequent amended boundaries, be available for public inspection in the offices of the administering agency in the District of Columbia and in locations convenient to the designated river.