Several undersized culverts in the towns of Addison and Columbia restrict water flow, and have not been able to handle recent high-water events.
Culverts, in most cases, are pipes embedded under a road, railway, or embankment to allow water to flow from one side to the other. They are an essential feature of any road that crosses over flowing water, preventing flooding and erosion while maintaining the path above. Unfortunately, the vast majority of culverts are impaired in some way, most commonly by being too small to pass the amount of water they regularly need to. An impaired culvert is more likely to be damaged in storms, increasing the chance of erosion and road damage.
Several road crossings and approaches in Addison and Columbia need replacement. While unfortunately these projects carry a hefty price tag, they cannot be ignored. The December 2023 and January 2024 storms highlighted the vulnerable condition of municipal infrastructure and roadways in Addison and Columbia. East Side Rd. at Knowles Brook (soon to be under construction) is probably the best known infrastructure need in Addison. Read more on that project from the Maine Department of Transportation (MaineDOT) here.
Within the West Branch project area, crossings at Addison Rd, Water St, Point St, and Ridge Rd flood during storms or are at risk of failing. Currently, however, the only crossing replacement on the MaineDOT work plan is Addison Rd, due to its advanced state of disrepair. The other crossings will be addressed as soon as possible, if supplemental funding is secured.
Ultimately, the goals of the longer-term restoration process are independent of what necessary repairs are done in the short term. The West Branch Project is interested in upgrading all these restrictive culverts to accommodate high water and improve public and road safety. The upgraded structures will require less frequent maintenance and improve access to emergency services following storm events.
Addison Rd. (Bell’s Brook) – Town of Columbia
The Addison Rd. crossing is in ‘Critical’ condition according to the rating system used by MaineDOT. The twin 72” round culverts are beginning to collapse, creating a large sag in the roadway. The sagging road has required repeated patching of large sections of the roadway in the last few years. Maintaining safe roads is MaineDOT’s primary concern, so repairing this culvert is a high priority project.
The high level of structural risk at Addison Rd means the crossing is frequently evaluated, but the timeline for repairs is in MaineDOT’s hands and will follow a standard process. Any new information will be shared as it becomes available.
In 2024, the Addison Rd. crossing replacement was awarded funding through NOAA’s Transformational Habitat Restoration and Coastal Resilience Grants program under the Bipartisan Infrastructure Law. However, the current administration terminated this $9 million grant in April of 2025. In response, the State of Maine filed a lawsuit against the National Oceanic and Atmospheric Administration (NOAA). State and federal partners are currently looking at ways to replace the lost funding and continue moving the project forward while the lawsuit is active.
From above, the extensive road repairs and the large pool below the culverts at the Addison Rd Crossing are unmistakable.
Point St. – Town of Addison
While the culvert pipe is still in acceptable condition, the Point St road surface has a very low elevation and is prone to flooding. During and after rain events the Point St. culvert becomes completely submerged, and the road itself has overtopped multiple times. Both sides of the roadway display signs warning of a potential water depth hazard. The Addison Point Water District supply line runs along Point St. and is at risk of degradation from external water exposure. Elevating the water supply line and raising the road would be essential components of improving this road crossing.
The tributary that passes under Point St. often floods the road after high precipitation events due to the low elevation of the road
Flooding at the Point Street culvert in 2005, prior to installation of the existing flood level signs. Photo courtesy of Marilee Lovit.
Water St. – Town of Addison
The primary Water St. culvert pipe is undersized, and there is an overflow pipe located higher up the embankment. A washout pool on the downstream side is visible, but not as large as the pool below the Addison Rd crossing. Current water flows don’t impact this culvert the way they do at other crossings, and are not presently causing degradation of the road surface.
Like the Addison Rd. crossing, a wide pool is visible below the Water St. crossing, compared to the thin trickle of water above
Beaver activity is also a concern at the Water St. crossing. Beaver fences prevent woody debris from clogging up the culvert pipe, but the main problem is the large beaver dam located upstream. If the dam were to fail catastrophically in a storm event it would cause significant damage to the Water St. crossing.
Looking downstream (top of image) from the massive beaver dam located between the Point and Water Street crossings
Ridge Rd. (“Clapper” Tide Gates; MaineDOT Bridge #3718)
The Ridge Rd crosses the mouth of the West Branch Pleasant River. The earthen dike includes a set of top hinged clapper tide gates to allow water to move downstream into the main stem of the Pleasant River.
Installed in 1940, the clapper gates were designed to provide one-way water movement, allowing freshwater to move downstream while blocking salt water from entering the West Branch. Today, some saltwater leaks through one or more broken gates on every tide, and during storms there is a chance that the outflowing freshwater and incoming storm surge will cause road washout conditions.
At high tides, salt water flows backward under Ridge Rd. as a result of one or more damaged tide gates
Water churns upstream through the culvert currently missing its tide gate
The tide gates and causeway are currently in poor condition, and will not stand up to future sea level rise. At a public meeting in 2009, MaineDOT bridge designer Michael Wight said the “bridge has serious problems.” On a scale of zero to nine, with zero being bridge closure, Wight rated the Addison bridge a three. For current information about the bridge structure, please refer to the MaineDOT’s public map viewer here (tip: enter 3718 into the search bar to go directly to the Ridge Road Dike Bridge).
To keep the road safe and functional, sometime in the future a decision on a replacement will need to be made. While MaineDOT will be responsible for designing and building any new structure, project partners are working with the towns of Columbia and Addison to find a solution that benefits both the upstream habitat and residents who own land in the historic floodplain.
US Route 1 – Town of Columbia
US Route 1 sits at the far northern end of the project area. Two culverts, one for Bells Brook and the other for Branch Brook, pass under US-1. One of these crossings was recently replaced, and the road is elevated enough that road flooding is not a present concern. These crossings are far enough north that they are not presently affected by the tide, but tidal water historically reached this far upriver and would again if the West Branch was made fully transparent to the tide.
Bells Brook crossing at US Route 1
Branch Brook crossing at US Route 1