Taking Root: Maine’s Shift Toward ‘Living Shorelines’
Article by Sonja Heyck-Merlin
In late 2023 and early 2024, back-to-back storms eroded 60-feet of shoreline on Little Diamond Island in Casco Bay. A massive community-led project to repair the extensive damage involved rebuilding the sand dunes with natural materials and incorporating native plants.
Little Diamond Island isn’t alone; Maine is losing large sections of its shorelines to erosion. Parker Gassett and Nathan Robbins believe that building “living shorelines” using nature-based solutions (NbS) for stabilization, like they did on Little Diamond Island, can help control it.
Gassett, assistant director of the Maine Climate Science Information Exchange, and Robbins, climate change specialist with the Maine Department of Environmental Protection (DEP), along with DEP colleagues John Maclaine and Jordan Kimball, are now crisscrossing Maine sharing a draft of a place-based guide of NbS for erosion control. It represents decades of institutional knowledge from engineers, geologists, state agencies, nonprofits, shoreline restoration practitioners, and the public.
The DEP published the guide, “” in 2024. At its simplest, NbS stabilization follows three steps: find the source(s) of erosion; stabilize the area with bioengineering techniques; and then establish a diversity of plants to hold the area in place.
“OUR SHORE was created to address a need for a trusted, Maine-focused resource on the wide variety of stabilization materials and techniques for both practitioners and property owners,” said Robbins.
Now that the draft guide is publicly available, Robbins, Gassett and other project partners are meeting with towns, community groups, contractors, engineers, and conservation organizations to promote it.
They’re answering a lot of questions: How to incorporate these strategies into an existing seawall? Where’s the best place to source native plants? Are coconut-based erosion control blankets worth the extra cost?
The questions are multifaceted because so are Maine’s shorelines. Highly erodible coastal bluffs, which make up 40% of Maine’s coastline, are largely composed of sand, gravel, and glacial till that yields easily to wave energy and storm surge. The shorelines of Maine’s freshwater ecosystems — streams, rivers, lakes, and ponds — are also susceptible to erosion. Increasingly severe storms and floods make erosion even worse.
The consequences run deep. Maine’s fishing and aquaculture industries, its tourism economy, and the biodiversity of its coastline and freshwater ecosystems all depend on healthy shorelines. So do the people who live within these ecosystems. Erosion is as much of a threat to Maine communities as it is to the natural landscape. This is especially true along portions of coastal and freshwater shorelines where roads, homes, and other infrastructure lie close to the water.
The OUR SHORE guide provides strategies to mitigate these impacts and ideally, prevent them. A contractor might consult the guide to understand what factors are contributing to erosion on a homeowner’s property; it could be caused by surface water, ice, or wave action. A landscaper can use the guide to understand the root structures of different native plants before they head to a nursery; a diverse root structure creates better soil stability. A nonprofit or individual homeowner can utilize the guide to learn simple livestaking techniques; a low-cost erosion control strategy that uses cuttings from living woody plants inserted directly into the ground along streambanks, slopes, or shorelines to bind soils and stones in place.
The need for such a resource reflects a long history of well-intentioned but damaging choices. For generations, to armor shorelines Mainers have turned to seawalls and riprap revetments — large angular rocks often installed with plastic geotextile landscape fabric. But hardened structures don’t dissipate wave energy; they deflect it sideways and downward, often worsening the erosion they were built to prevent. They also eliminate native habitat and damage the ecosystems they were meant to protect. Yet even within these conventional approaches, there is room for change. Robbins points out that incorporating vegetation into hardened designs, called a hybrid green-grey approach, can actually strengthen them over time.
Changing how Mainers approach shoreline erosion won’t happen through a guide alone. From the beginning, Gassett and Robbins recognized that shifting public thinking requires collaboration. In 2022, they launched a joint Mitchell Center–Maine DEP internship focused on NbS for stabilization.
Two Mitchell Center student interns, Melissa Genoter and Karina Cortijo-Robles, conducted interviews across state agencies, municipalities, and practitioners. Their work as trusted intermediaries helped lay the groundwork for what became OUR SHORE. Gassett, who also serves as a Mitchell Center faculty fellow, thinks that without them, some of those conversations would have been harder to have.
“People are more candid when they speak to young people because they’re held to a high standard of sincerity, so student research projects have a way of dissolving barriers,” said Gassett.
Genoter’s work showed the DEP that they needed to engage earlier and more often with NbS stabilization practitioners, a finding that reinforced Robbins’s commitment to community engagement. Cortijo-Roble’s internship built upon this by developing the program’s framework. When the internships wrapped in 2024, that momentum fed directly into the OUR SHORE guide.
This collaboration demonstrates how the Mitchell Center is effectively supporting statewide initiatives in their early stages, before transitioning to a more state government-led approach as programs mature.
This foundational work also spurred changes in regulations with Maine now requiring greater justification for traditional hard structures. People applying for permits to use hardened structures must demonstrate that there is a specific need for that protection, like a structure, road, or driveway within 100 feet of the shoreline. Even when structural work is necessary and allowed, the new regulations ask landowners to minimize the use of hard structures. Sometimes a permit might be returned with suggestions for a combination of NbS for stabilization with traditional hardened structures.
The regulations also streamline permitting for projects using primarily biodegradable materials, making it much easier to get approval. There are new exemptions for small-scale projects. People are now allowed to slit-plant an unlimited number of livestakes and bare-root plants, a method that involves creating a narrow, vertical slit in the soil to insert the plant material, minimizing disruption to the soil structure. There are also no restrictions on reseeding soils for denser cover.
The OURSHORE team believes the next phase of the project — hands-on community engagement — is their most important job. In July 2025, they helped train the first cohort of , who will bring their new knowledge to organizations across the state. The team is also demonstrating specific NbS stabilization techniques — like how to transplant plants from one part of a property to an eroding bank — to communities across Maine.
Based on the concepts in the OUR SHORE guide, Gassett, Maine Sea Grant, the DEP, and the Maine Coastal Program are developing a micro-credential for practitioners that will provide certification in NbS stabilization techniques. It will offer deeper training for those who want to gain more specialized skills.
The destructive storms in 2023 and 2024 and other extreme weather events have added salience and urgency to the team’s community engagement efforts. “Maine’s coast is taking a beating from winter storms,” said Gassett.
The OUR SHORE team and agency partners continue to work with geologists, engineers, and contractors to evaluate a growing number of stabilization sites across Maine. They include a 2,000 foot-long living shoreline project in Blue Hill that’s creating new marsh habitat, and a Department of Transportation project on the Androscoggin River where, after 10 years, a fully vegetated bank is performing as well as or better than a section reinforced with only riprap.
The OUR SHORE team believes examples like these benefit public infrastructure, ecosystems, and community well-being. They’re also aware that every project presents site-specific challenges. NbS for stabilization are not a panacea for shoreline erosion, but they are part of the solution. Even when hard structures are called for, plants can be incorporated into the project design.
“We have learned that nature-based designs are a critical component of how we should be thinking about resilient infrastructure, and they should be applied whenever possible and wherever appropriate,” said Robbins.