You can’t see any fish, flying as we were 900 feet above the river. But we knew they were there, moving upstream to spawn.

Flying over the Kennebec River was a fascinating experience and I was grateful for the opportunity to look at the watershed from above, to see and think about the efforts that have been going on over decades to improve the waters of this once magnificent but also once tragically polluted waterway.

Nine years ago, almost exactly to the day, I’d had the same opportunity to fly over the river following the day-long Conference on the Kennebec organized in Waterville by Maine Rivers, thanks again to the generosity of the nonprofit LightHawk.

Conservation biologist Dr. John Waldman was the conference’s keynote speaker and joined me on the 2014 flight. He’d offered his assessment of the Kennebec and its potential, noting the history of the destruction of the once-great fisheries of the Eastern Seaboard because of overfishing, dams and pollution.

One of the most powerful points which he made to us that day in Waterville is that, from Labrador down to Florida, of all of the rivers flowing into the western Atlantic Ocean, he finds the Kennebec has the greatest diversity of aquatic species, species which include Atlantic salmon, Atlantic sturgeon, short-nosed sturgeon, striped bass, American shad, alewife, blue-back herring, rainbow smelt, tomcod, American eel, and  sea lamprey. Merrymeeting Bay, part of the Kennebec estuary system, brings together six rivers — a global rarity of rich and threatened diversity.

Over the nine years between flights, remarkable work has been completed, including the China Lake Alewife Restoration Initiative; work that fully removed three non-hydro dams and installed technical fishways (fish ladders) at three other sites. Maine Rivers was an integral part of that work, celebrating success last year as more than 800,000 native adult alewives were counted swimming into the lake for the first time since 1783.

It was a thrill to fly over the river and know that under us, in the water, life was returning to rebuild and revitalize food webs and water quality. Also worth celebrating is the recent removal of the Walton’s Mill dam in Farmington, where another stream flows freely for the first time in 240 years, thanks to Farmington voters who approved plans put forward by the Atlantic Salmon Federation, plans that included park improvements and the replacement of two road-stream crossings, to benefit the local community as well as Atlantic salmon and brook trout.

The four mainstem Kennebec dams owned by the mega-energy company Brookfield remain highly problematic. I’ve heard every form of argument against conservation and river restoration, from concerns that no fish will benefit to more bizarre thoughts that too many fish will return. What do researchers find about the benefits?

Dr. Lynne Y. Lewis, professor of economics at Bates College, recently shared with me the undergraduate thesis of her advisee, Tamsin Stringer; work that builds on Lewis’ own assessment of the real-world impacts of dam removal on property values. Stringer looked at individual property values to see how proximity to the Kennebec River impacts property values. She investigated the differing impacts for towns with dams versus towns without, and further asked if there is a significant difference between property values upstream versus downstream of large dams. To do this she analyzed single-family home sales data from Redfin, a real estate listing site, for the towns of Pittston, Gardiner, Farmingdale, Augusta, Hallowell, Vassalboro, Winslow, Waterville, Fairfield, Skowhegan, Norridgewock and Madison.

All the towns she investigated are located on the main stem of the lower Kennebec and to conduct the analysis she looked at home sales from 2017 to 2022, tallying total of 3,099 house sales. The work included a regression analysis with 11 variables, relating to the size of the homes and distance to the river.

In short, the work confirms that homeowners downstream of Waterville’s Lockwood dam, where the river is free flowing, all benefit from being closer to the river. Upstream of that dam and the three other Kennebec dams, the river and dams have a negative impact on property values. Her analysis concluded that the towns in which the dams are located, Waterville, Fairfield, Skowhegan, Norridgewock, and Madison, all have negative values.

More work in the realm of economics remains to be done. Can it be done fast enough to balance the threats to our freshwater ecosystems, where worldwide today a third of freshwater fish species are threatened with extinction? Can the rebirth of the Kennebec bring together ecological and economic revitalization?