Presumpscot River Corridor Landslide Vulnerability Assessment Study

Purpose of Study

The Presumpscot River Corridor Landslide Vulnerability Assessment Study is a regional collaborative project to understand our local soil conditions as it relates to landslide action. This effort is funded through a $986,500 Congressionally Directed Spending Grant sponsored by Senator Susan Collins and Senator Angus King, with an additional $120,000 in matching funds from MaineDOT’s Infrastructure Adaptation Fund.

This study strives to accomplish three goals:

1. Identify triggers and attributes of the September 2020 landslide;
2. Explore potential policy (e.g., model ordinance, overlay zone, etc.) to minimize future losses from landslide action; and
3. Identify and prioritize the most vulnerable areas in the Presumpscot River Corridor 

Why this Project Matters

The City of Westbrook and the surrounding areas have a history of landslides. Landslides pose a hazard to property, safety, habitat, and even human life. 

Even small landslides can disrupt daily life, damage property, and strain city resources. This assessment helps us prevent emergencies, reduce long-term costs, and make Westbrook and the surrounding areas more resilient to natural hazards. 

About the Project

In Summer 2025, the University of Maine College of Engineering, in partnership with Maine Geological Survey and other technical experts, carefully selected areas for soil testing based on where past landslides have occurred. Contractors will be in selected locations exploring below ground to collect samples and study the strength and stability of the soils. This will help us to understand where soils are susceptible to landslide action and development standards for these vulnerable areas. 

Costs associated with this project, including a stipend for a PhD-level graduate student and subject matter experts (SMEs), as well as contractors and testing, are funded through the grants mentioned above. The subject matter experts are technical professionals who will review the field work overseen by UMaine geotechnical engineers and help guide the City of Westbrook in policy for future work on or near the Presumpscot River corridor. The SME panel includes Geotechnical Engineers and Geologists who work throughout Maine, and are experts in landslides, hydrogeology, engineering, and other technical specialties.

The team of technical experts are evaluating different types of specialized equipment to determine what information each can provide accurately and reliably. Some tools can measure how much pressure the ground can handle before it becomes unstable, while others help identify areas where the soil is especially weak or fragile. This helps pinpoint spots that may be at higher risk for future landslides.

Data will be gathered throughout September, October, and November. UMaine will work diligently to compile and analyze the data before sharing it with the panel of SMEs. Maine Geological Survey will utilize the data to create a landslide susceptibility map, which will be the basis for future planning and policy. Stay tuned for more information in Spring 2026.

Click here to see Channel 8's coverage of the 2020 landslide.

Click here to see AP News' coverage of the 2020 landslide.

Click here to see the presentation Portland Water District gave to Governor Mills.

Click here to see the Press Release from Senator Susan Collins' Office Regarding the Grant Award.

Project Milestones

• 9/5/2025 Press Release for the Presumpscot River Corridor Landslide Vulnerability Assessment Study drill rigs announcement. 

Municipal Project Partners

The City of Westbrook is proud to be working with the following municipalities on this study: 

Portland, Falmouth, Gorham, Windham, Standish, Casco and Westbrook are sharing data and engaging in discussions with experts to help shape Maine’s first regional approach to landslide hazard planning.

Organization Project Partners

The City of Westbrook is also proudly working with the following organizations on this study:

Click here to see the presentation given to the Cumberland County Emergency Management Agency

We would like to thank our partner towns, agencies, and experts for their support of this important work. Together, we’re building a safer, stronger Southern Maine!