A summer view of the South River from the Francis Keville Bridge in Marshfield.
Are you aware that we have a nationally recognized landscape in our midst? Like California’s Mount Shasta, the Okefenokee Swamp in Georgia, Kentucky’s Red River Gorge and Ship Rock in New Mexico, the North and South Rivers are one of our country’s National Natural Landmarks.
In 1977, the National Park Service and the Department of the Interior designated the North and South Rivers of Plymouth County, Massachusetts, a National Natural Landmark (NNL). The rivers were recognized as “possessing national significance in illustrating the natural character of the United States,” The area of designation comprised 5400 acres, including over 3600 acres of saltwater marsh.
While the designation went into effect 40 years ago, until now it has lacked a public face. However that’s about to change. On September 23, Congresswoman Nikki Tsongas will appear at a celebratory rededication of the rivers’ National Natural Landmark status. At 1pm there will be a ceremony at South River Park (2148 Ocean Street), where a plaque marking the designation will be installed. The event will also honor the late Senator Paul Tsongas’s commitment to the rivers of Massachusetts.

Tsongas was instrumental in obtaining the designation in the first place. Efforts began in the early 1970s, when former Pembroke residents Jean & Jack Foley, Marshfield resident Bill Finn, and other members of the North and South Rivers Watershed Association, nominated the rivers for the NNL program.

In September 1977, the Foleys and Finn provided a boat tour of the North and South Rivers to Dr. H. W. Vogelmann Ph.D., who had been contracted by the government to review the rivers for NNL designation. Vogelmann also viewed the area from an airplane, and at the end of the year submitted an evaluation to the Department of the Interior, recommending that the rivers receive the designation.

Vogelmann observed that, “the marshland systems of the North and South Rivers are extensive and complex,” and noted that the rivers were “classic examples of drowned river mouth estuaries.” He said, “Extensive marshland systems and relatively unpolluted rivers are a rare occurrence near a metropolitan area like Boston.”

National Natural Landmark status was conferred soon thereafter. This was especially significant because until then, the program had only accepted more nationally well-known sites. There were only 66 NNLs at that time.

“But nothing happened,” remembers Finn.

The official designation date for the North and South Rivers as a National Natural Landmark is 1977. But according to Finn, it took several years for the designation to be declared. Repeated inquiries to the National Park Service (NPS), attempting to determine whether or not the rivers would receive the designation, yielded nothing. Finally in 1979, after Tsongas was elected to the US Senate, the wheels began to turn. Theta Leonard, who worked for Tsongas, along with the senator and Bill Finn, collaborated with the NPS to tie up loose ends.

Finally in May 1980, during the second annual Massachusetts Rivers Celebration, a dedication ceremony was held at Mass Audubon’s North River Sanctuary in Marshfield. Tsongas, several local political figures, as well as representatives from the NPS and other state and federal agencies, joined NSRWA members and officials for a canoe trip down the North River. Two wooden signs were presented, but they were not the type that could be installed outdoors. With the installation of the plaque on September 23rd, the final loose end will – finally! — be secured.

Samantha Woods, current Executive Director of the NSRWA, recently commented, “The foresight of the organization back in 1977 to obtain this National Landmark Designation has truly helped the rivers. In fact the South River Park, where the new plaque commemorating the designation is to be placed, couldn’t have been built without a $250,000 Land and Water Conservation Grant that was enabled, in part, because of this national recognition of these two rivers as being unique to the nation’s natural resources.”

According to the NPS “the National Natural Landmarks program recognizes and encourages the conservation of outstanding examples of our country’s natural history.” To date, 599 sites have been designated. In order to obtain NNL status, the site must be “one of the best examples of a natural region’s characteristic biotic or geologic features.”

Secretary of the Interior Stewart Udall founded the program in 1962. Its primary goal is to “encourage the preservation of sites illustrating the geological and ecological character of the United States, to enhance the scientific and educational value of sites thus preserved, to strengthen public appreciation of natural history, and to foster a greater concern for the conservation of the nation’s natural heritage.”

All sorts of different landscapes may be considered for NNL designation. The present sites include lands used for ranching, agriculture, recreation, nature preserves, research areas, camps, conference centers, and commercial ventures. They vary in size from a 7-acre bog to a 960,000-acre glacier. Some, like Connecticut’s Dinosaur Trackway, involve only a single remarkable feature, while others encompass large, widely diverse landscapes. Public access is not a foregone conclusion. Some NNLs may be too ecologically fragile to permit visitors – or it might be the best remaining example – in the country, or even worldwide — of a certain, often irreplaceable, type of landscape feature. Unlike the lands in the National Park system, National Natural Landmarks are not owned or managed by the federal government. They may be privately or publicly owned.

The Natural Landmark program’s aim has been ”to encourage and support voluntary preservation of sites that illustrate the geological and ecological history of the United States, and to strengthen the public’s appreciation of America’s natural heritage.” In order to maintain NNL status, the only requirement is that the “significant natural values of the site” are preserved as much as possible. No new land use restrictions are set upon the site. The NPS does make occasional visits to verify a site’s condition and maintain good rapport with landowners.

To learn more about National Natural Landmarks, and to read a complete listing of NNL sites, visit

by Kezia Bacon
August 2018

Kezia Bacon’s articles appear courtesy of the North and South Rivers Watershed Association, a local non-profit organization devoted to protecting our waters. For membership information and a copy of their latest newsletter, contact NSRWA at (781) 659-8168 or visit To browse 22+ years of nature columns, visit