(This measure has not been amended since it was reported to the Senate on April 22, 2013. The summary of that version is repeated here.)
Harriet Tubman National Historical Parks Act - Establishes in Caroline, Dorchester, and Talbot Counties, Maryland, the Harriet Tubman Underground Railroad National Historical Park as a unit of the National Park System.
Establishes in Auburn, New York, the Harriet Tubman National Historical Park also as a unit of the National Park System.
Authorizes the Secretary of the Interior to enter into cooperative agreements with certain entities for the historical preservation and interpretation of the parks.
Requires the Secretary to complete a general management plan for the parks.
Amends the Water Resources Development Act of 1996 to decrease the federal share of project costs for navigation and safety improvements to the Chesapeake and Delaware Canal and Baltimore Harbor Connecting Channels in Delaware and Maryland.