How Stormwater Impacts Casco Bay’s Coldwater Community: A Story of Two Maine Mermaids

Two Maine Mermaids foster community through cold water dips, but stormwater pollution threatens these cherished moments.

Braving the chill and the challenges, cold water dippers take on Willard Beach all year long. Credit: Alyssa Soucy.

For Caitlin Hopkins and Kelsy Hartley, cold water dipping in Casco Bay is more than a practice—it’s a way of life. What began as a personal journey for each of them has grown into a movement that fosters joy, community, and connection to nature. As the Two Maine Mermaids, they host coldwater dipping events along the coast of Maine and have become known for their full moon events and annual Women’s Wave. But their beloved cold dips face an increasing challenge: the impacts of stormwater pollution.

Stormwater—rain and snowmelt that runs off roads, rooftops, and other hard surfaces—often carries oil, debris, pesticides, untreated waste, excess nutrients, and bacteria into waterways. After significant storms, this pollution can make coastal waters unsafe, threatening marine life, ecosystems, and the people who seek solace and adventure in the waves.

For the founders of Two Maine Mermaids, the consequences of stormwater pollution hit close to home. “We’ve had to cancel two of our Full Moon Dips this past year because of water quality concerns after heavy rain,” Kelsy shares. “It’s heartbreaking—not just because we lose the event but because it’s a reminder of how much these waters are struggling.”

Building a Movement by the Bay

The Two Maine Mermaids: Kelsy Hartley (aka Ebb) and Caitlin Hopkins (aka Flow). Credit: Alyssa Soucy.

Caitlin began swimming in open water in late 2019, drawn to the ocean’s restorative power. “The water has always felt like a safe space for me,” she shares. As winter approached, she kept returning to the ocean to dip with friends. “It’s like a reset button—physically and mentally.”

For Kelsy, dipping started as part of a personal healing journey. “In 2019, I was getting sober and having a really hard time. Something about cold water just called to me,” she explains. “It supported my mental health in ways I couldn’t even articulate back then.”

Their shared love for the ocean brought them together, and they created Two Maine Mermaids to celebrate three principles: spreading joy, connecting with nature, and building community. Their flagship events, like the Full Moon Dip, bring dozens of participants into the icy waters of Casco Bay each month.

In November, Friends of Casco Bay joined the Mermaids for one of these unforgettable Full Moon Dips, deepening the connection between our two organizations. Both groups share a commitment to protecting the health of Casco Bay so everyone—humans and marine life alike—can enjoy the benefits of clean, resilient waters.

When Storms Bring Pollution

Over time, the Mermaids noticed patterns in the water. After storms, they often saw debris, smelled foul odors, and felt uneasy about what might be lurking unseen. “We’ve had to ask ourselves, ‘Should we even be swimming in this?’” Caitlin admits.

In the Greater Portland region, stormwater and sewage often share the same pipes. Rains can flood the sewer lines, causing combined sewer overflows to open, releasing both stormwater and raw sewage into Casco Bay.

The decision to cancel an event is never easy, but bacteria data from the state provides critical guidance. Caitlin says, “We rely on the reports to decide if it’s safe.”

Friends of Casco Bay’s work to address stormwater pollution helps groups like Two Maine Mermaids. From collecting data on the health of our waters to advocating for stormwater policies like Maine’s Stormwater Resolve, our efforts aim to reduce pollution and ensure cleaner, healthier waters for everyone.

Unfortunately, pollution has made some dips difficult to maintain. “Our weekly Workout-and-Dip events became so unreliable last year that we had to stop offering them,” says Kelsy. “It’s sad because these events create consistent access to the water. Losing them is a reminder of how limited that access already is for many people.”

A Shared Call to Protect Casco Bay

For Caitlin and Kelsy, cold dipping isn’t just about personal well-being—it’s about forging a deeper connection with nature and raising awareness about its fragility. “You can’t unsee the impacts of the climate crisis once you’ve witnessed two 100-year storms and the fishing shacks being washed away,” Kelsy reflects. “There are profound, immediate effects in everyone’s community. It’s important that we’re feeling the pain of it so we can take action, but it’s incredibly sad.”

Both the Mermaids and Friends of Casco Bay believe education is a powerful tool for change. “When we cancel an event, we explain why,” Caitlin says. “It’s a chance to help people understand pollution and climate change and how these things impact them.”

Stormwater pollution may be a challenge, but the Mermaids are determined to keep their mission alive. “We dip as a community because it builds a heart-to-heart connection,” Kelsey says. “There is no hierarchy out there in the water. We’re all there together.”

Join Friends of Casco Bay at the 2025 Women’s Wave!

Ready to take the plunge! Cold water dippers line up for the Annual International Women’s Day Dip 2024 at Willard Beach. Credit: Alyssa Soucy.

Looking for a fun way to celebrate International Women’s Day while connecting to Casco Bay? Two of the incredible women of our organization—Meghan and Sara—will be participating in the 5th Annual Women’s Wave, hosted by Two Maine Mermaids. We encourage you to join us in braving the Bay!

What: The Women’s Wave—the largest and coldest celebration of International Women’s Day in the country!
Where: Willard Beach, South Portland
When: Saturday, March 8 | Gather at 9:30 a.m. | Dip at 10:00 a.m.
Weather Date: Sunday, March 9
Register here!

This year’s goal is ambitious: to have 1,000 dippers lining the 2,100 feet of Willard Beach shoreline in a powerful demonstration of strength, unity, and ocean advocacy.

Join us for this unforgettable event as we wade into the cold water to celebrate women and our connection to Casco Bay. Invite a friend and make some waves with us!