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Emma and Lorren’s site visits to Chebeague Island
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Coastal bluff erosion seen on Chebeague Island
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Coastal dune erosion seen on Chebeague Island
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A nature-based strategy demonstration project located on Little Diamond Island in the Casco Bay

Coastal Resilience

Coastal resilience on Chebeague Island 

So much of the state of Maine has been changing before our eyes. Localized impacts vary, but generally, we have seen an average annual erosion rate of approximately 1 foot per year, paired with a rate of sea level rise that has increased 7-12 inches in the last century depending on your location (GMRI, 2018). These rates, along with additional major events like the January 2024 storms, lead to sudden coastal bluff instability and dune loss. Some beaches in Southern Maine saw a 28% dune loss between January 10th and 13th in 2024. These storms had a massive economic impact throughout the state - $70 million in damages to coastal properties and public infrastructure alone (University of New England, 2025). From an economic and place attachment perspective, climate change impacts have put Chebeague Island in a position where we must learn and act with a rapidly changing future in mind. Those same storms saw Chebeague accrue over $1 million in damages to coastal property and public infrastructure. As a municipality, the Town of Chebeague has been making moves to prioritize coastal resilience with this uncertain future top of mind. We know that we have seen changes on our shoreline as a result of erosion and storm surge. As a community and as a town, we have options in responding to these issues. Our options may include but are certainly not limited to the following: 

  1. Do nothing: after considering how vulnerable a structure is, it may make sense to do nothing because the risk is low 
  1. Avoid: communities proactively avoid placing additional infrastructure into areas of high flood or erosion hazards 
  1. Accommodate and Adapt: existing infrastructure can be adapted, such as raising up structures on posts; accommodation includes using increased setbacks and vegetative buffers to help provide buffers to storm surges 
  1. Protect: through using nature-based solutions (where appropriate), hard armoring (when necessary), and/or maintaining existing seawalls and/or making them more resilient and less damaging to adjacent habitats 
  1. Relocate or Remove: Based on risk and vulnerability, it may make the most sense to relocate landward, if possible.  

Municipal guidance and policy decisions can be taken to make the above more straightforward and perhaps easier for the community. Lorren Ruscetta, The Island Institute Fellow serving Chebeague, has been focusing on all things coastal access and resilience. Lorren has been working to build her local knowledge, paired with state regulations, to develop a comprehensive understanding of our options as a town. Luckily, there are resources abound to help navigate these decisions. Below you will find some specific maps that can continue setting the context for why this is a timely and important issue facing Chebeague. You’ll then find more information about state-supported guidance and principles regarding nature-based strategies.  

Maine Geological Survey Coastal Bluff Stability map 
Maine Sand Dune Erosion Hazard Areas map 
Sea-level Rise & Storm Surge map 


Maine Department of Environmental Protection’s OURSHORE Program 

But first, here are some terms to understand! 
Shoreline stabilization: Often called shoreline hardening or armoring, this typically refers to building hard, manufactured structures (like seawalls, bulkheads, and/or riprap) along a coast or water's edge to attempt to stop erosion and protect private property. Shoreline stabilization can also refer to plants and natural materials used for the same purpose. 
End-effect erosion: Worsened coastal erosion that happens at the ends of protective structures like seawalls or riprap, causing increased damage to neighboring properties by disrupting natural sediment flow, essentially pushing the erosion problem next door in a domino effect 
Scouring: An effect that occurs when waves hit a hard, vertical wall. That wave energy is not absorbed; instead, it is reflected downward and sideways. This redirected, high-energy flow "scoops out" and carries away the sediment (sand, soil, and/or sea bottom) at the base of the structure and in adjacent areas. Consequences of scouring include deepening the water in front of the structure and creating more intense wave energy, degrading habitat, and the undercutting of the foundation of the hardened structure leading to failure of the structure 
Nature-based strategies (for shoreline stabilization): Strategies that utilize natural processes and ecosystems to address environmental challenges. For shoreline erosion, several nature-based solutions can be employed to manage and mitigate erosion while also providing additional benefits to the ecosystem 
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In response to these increasing coastal hazards, the Maine Department of Environmental Protection (DEP) has been navigating questions from coastal communities across the state about how to respond and has been receiving an influx of permit applications for shoreline stabilization projects. At the same time, new research is showing that hardened shoreline structures like rip rap have many unintended consequences for communities and the environment: end-effect erosion and scouring, expensive maintenance and replacement costs as structures break down over time, and damage to rare and important shoreline habitat. These issues have cumulative effects as more of our coasts are hardened.  

While many people first think of riprap or seawalls when they are considering their options for coastal erosion management, there are other tools available. Nature-based strategies (NbS) for mitigating erosion use living, natural, and biodegradable materials to stabilize and protect shorelines. NbS and structural stabilization can also be combined to create hybrid infrastructure designs. Case studies of nature-based and hybrid strategies show that they can effectively stabilize eroding shorelines while minimizing end-effect erosion and protecting coastal habitats. However, NbS can be challenging for property owners and contractors to implement because of gaps in reliable technical guidance and clear permitting pathways.  

The DEP is currently developing OUR SHORE, a program that seeks to support homeowners, contractors, and communities who want to integrate NbS into their plans for coastal resilience. The program provides informational tools in the form of a quick assessment to identify erosion hazards and a longer guide on how to apply NbS techniques, as well as outreach and training events for homeowners and shoreline stabilization practitioners. 

See below for some actions the Town of Chebeague has taken with the support of partners from the Island Institute and state agencies. 

Actions 

Chebeague Island has long been focused on climate planning as a municipality, and coastal resilience is an area of particular focus. The town has worked with consultants from GEI and FB Environmental and organizations like Island Institute to promote capacity and leadership in understanding community priorities within coastal resilience. Part of the work of the Island Institute Fellow is to continue supporting these coastal resilience measures through collaborating with state agencies and local organizations. 

OUR SHORE and the Maine Conservation Corps are collaborating to provide direct technical assistance on NbS to property owners and communities by placing Shore Corps Stewards with nonprofits across the state of Maine. Each Shore Corps Steward receives specialized training from the OUR SHORE program and state partners. From May 2025–May 2026, Island Institute is hosting a Shore Corps Steward, Emma Polhemus, to support the Town of Chebeague Island and other Casco Bay islands as they expand NbS opportunities for public and private properties.  

In November 2025, Emma visited Chebeague to complete five coastal erosion site assessments using the OUR SHORE Quick Assessment Tool. Site assessments took place at two private properties and three municipal rights of way: Hamilton Beach, Division Point, and South Shore Drive. Island Institute Fellow Lorren Ruscetta, Island Institute staff members, Town of Chebeague Island Selectboard members, the Town Code Enforcement Officer, and neighboring property owners gathered at each site to provide a wealth of local knowledge and subject matter expertise to supplement the assessments. Using the information gathered at these visits, Emma is drafting reports that will share erosion assessment results and recommendations for nature-based, or hybrid strategies tailored to each site. 

Future Actions 

  • In Spring 2026, Island Institute Shore Corps Steward Emma and Island Institute Fellow Lorren will host a community presentation to share the OUR SHORE recommendations.  
  • TOCI demonstration project at Hamilton Beach using nature-based strategies 

More details on these future actions to come! Stay tuned. 


Resources 

  • Maine Geological Survey Resources 


Sources used: 

https://storymaps.arcgis.com/stories/58565bc31955414c85b5464de5374ffd 

https://www.gmri.org/stories/gulf-maine-explained-sea-level-rise/