On a sweltering day in August, the beach at Range Pond State Park in Poland is packed. Kids splash in the water and families camp out underneath the pine trees, grilling hot dogs and trying to stay cool. But Bonnie Knightly says the water doesn’t feel as refreshing as it should.
“It’s warmer than I remember the lakes and ponds being this time of year,” Knightly said. She’s been coming to Range Pond for years, but can’t remember the water being so warm this early in the summer. “Maybe the end of August, but not the beginning.
And it was even two weeks ago when we were here. It was like this. So, yeah, it’s different,” Knightly said.
Maine is home to almost 6,000 lakes and ponds, with some of the cleanest, clearest water in the country. But many are under threat from climate change. Water temperatures are skyrocketing.
The growing season for algae and invasive plants is getting longer. And intense rainstorms are accelerating erosion, injecting more pollutants into watersheds. Average surface water temperatures in almost 100 Maine lakes rose 5.
5 degrees Fahrenheit between 1980 and 2020, according to long-term monitoring by the Maine Department of Environmental Protection. That’s faster than the annual air temperature increase and outpaces changes in the Gulf of Maine, one of the fastest warming bodies of water on the planet. Danielle Wain, science director for Seven Lakes Alliance, a conservation nonprofit in Belgrade, said rapid warming means profound change.