FALMOUTH — Once seen only for its potential to drive industry, the 25-mile long Presumpscot River, which flows from Sebago Lake to Casco Bay, is now valued almost as much for its natural beauty.

The river “is special because it has historical resonance,” Michael Shaughnessy, president of the Friends of the Presumpscot River, said. “… In many ways the story of America is reflected in the waters of the Presumpscot.”

Shaughnessy will give a talk on the history of the river and the efforts to restore it during a special Falmouth 300 event at 6:30 p.m. July 19. The event, which is free and open to the public, will be held at the Falmouth Congregational Church.

The talk, entitled “The Presumpscot River: An Environmental History,” is part of the Changing Landscapes, Shifting Tides: The Story of Falmouth series. Although it’s free, pre-registration is required. Go to the Falmouth 300 website, at www.falmouth300.org, to sign up.

Shaughnessy is a co-founder of the Friends of the Presumpscot River and said the group got going in 1993 to fight a proposed pulp mill on the upper part of the river that would have “discharged thousands of gallons daily of heated water.”

“We stopped this and then continued advocating for the river,” he said. “At that time few would support the river and recognize its value. Few knew what a gem it was.”

In the past 25 years of advocacy and outreach, Shaughnessy said the friends group has “gained river upgrades, been a collaborator on one dam removal and gained federal fish passage requirements on five dams,” among other achievements.

“We have a mission of educating (people) about the river and have hosted many talks on river restoration, fly fishing, river history, fisheries, and the first people of the river. We talk in schools constantly, have film showings and (hold group) floats and river cleanups,” he said.

In addition, the friends group is in the process of building a memorial to Chief Polin and the first people of the Presumpscot River, said Shaughnessy, a Westbrook resident who has lived along the banks of the Presumpscot since he moved to Maine from Missouri in 1987.

“Coming from Missouri, we had always floated rivers in the Ozarks. We were stunned at the beauty of the Presumpscot and could not understand how it was not recognized more,” he said. “Anywhere in the Midwest, this would be a state treasure.”

Shaughnessy said the Presumpscot River is known as the “river of waterfalls” because it originally boasted 12 sets of falls. “Sadly, however, most of these falls are (now) buried beneath concrete dams,” he noted.

He said there are only three falls that can still be seen, including Presumpscot Falls in Falmouth, which Shaughnessy described as a place of “peace and renewal where we can connect to the pulse of the planet.”

In terms of Falmouth’s relationship with the river, Shaughnessy said, “it was in Falmouth that the first land purchase from the Native Americans occurred.”

Originally the waters were used to manufacture whiskey, but then, he said, “other industries began to grow up on the lower river and estuary. Much of (that) was wood processing and shipbuilding.”

Shaughnessy said Falmouth was also “the site of the first dam on the river and ironically, the site of the first dam removed from the river.”

What Shaughnessy wants people to most understand, he said, is that the river is “not simply a place to swim, float, fish and paddle,” but one that should be valued and sustained for generations to come.

What he wants is for “people to simply fall in love with the river. Immerse yourself in it. Revel in its beauty, feel it and smell it. Wonder at the miracles that exist within it. Then support efforts to repair the harms of the past and protect it for the future.”

Shaughnessy said people who wish to become involved should “be politically active, advocate to leaders on the importance of protecting and enhancing water quality and fishery restoration (and) join, and donate time and money to organizations like FOPR that are willing to fight for the river.”

He said the biggest threats to the river are “pollutants coming from sewer, stormwater, and industrial discharges.” But, Shaughnessy also said, it’s vital to “as much as possible keep the shorelands in a healthy natural state.”

“How we treat our river says much more about who we are than about what it is,” he said. “This river is a gift we can pass on to future generations (and) it must be done with love and care. We belong much more to the river than the river belongs to us.”

Kate Irish Collins can be reached at 710-2336 or kcollins@theforecaster.net. Follow Kate on Twitter: @KIrishCollins.

Presumpscot Falls in Falmouth is a key attraction of the Presumpscot River, and a popular place for fishing and picnicking.

Paddling a kayak or canoe are among ways to enjoy the Presumpscot River, which flows 25 miles from Sebago Lake to Casco Bay, passing through Falmouth on the way.