A bill to amend the Chesapeake and Ohio Canal Development Act to suspend the use of eminent domain within any part in any county which has in force a valid zoning bylaw, and for other purposes.

Suspends the powers of the Secretary of the Interior to acquire land by condemnation with respect to any improved property within the Chesapeake and Ohio Canal National Historical Park in Montgomery, Frederick, Washington or Allegheny Counties in the State of Maryland, during any period when the county within which such improved property is located has in force and applying to such improved property a valid zoning bylaw approved by the Secretary.

Requires the Secretary after consulting with the counties involved, to issue regulations specifying standards for approval by him of such zoning bylaws. Prohibits approval by the Secretary of any zoning bylaw which contains any provision adverse to the preservation and development of the park. Sets forth conditions under which the Secretary may terminate the suspension of his authority to acquire such improved property by condemnation. Requires the Secretary to furnish to any party in interest requesting the same, a certificate indicating that such authority to acquire property by condemnation has been suspended, and stating the reasons therefor.