Bath Flood Vulnerability Assessment
An assessment of road vulnerability to flooding from storm surge, sea level rise, and extreme riverine events for the City of Bath
Presented by GEI Consultants, the Gulf of Maine Research Institute, and the City of Bath
GEI Consultants assessed the vulnerability of infrastructure and open spaces to flooding from storm surge, sea level rise, and extreme riverine events. The purpose of the work was to evaluate present-day flood risk, flood risk in 2050, and flood risk in 2100 and recommend next steps towards adaptation, including timelines for when adaptation measures should be in place to limit the impact flooding may have on people, places, and infrastructure within the City of Bath.
Scroll below to explore neighborhoods at risk of flooding and possible flood impacts.
Flood Vulnerable Neighborhoods
Present Day Coastal Storm Conditions
For present day sea levels, approximately 725 ft of Washington Street and 103 ft of Harward Street, near the intersection of the two, are at risk of inundation during a combined 100-yr coastal and riverine storm event.
The peak water surface elevation for the storm event is estimated to be approximately 8.9 ft, which would inundate Washington Street and Harward Street with depths of up to 3.5 ft and 1.2 ft, respectively.
Washington Street would likely be inundated between 6 and 7 hours during the peak of the storm, with additional periods of inundation likely during high tides on either end of the peak of the storm.
The end of Harward Street near the intersection of Washington Street would likely be inundated between 3 and 4 hours during the peak of the storm, with additional periods of inundation likely during high tides on either end of the peak of the storm.
2050 Average Conditions under 1.5 ft of Sea Level Rise
By 2050, approximately 235 ft of Commercial Street, north of the Summer Street intersection, would likely be at risk of flood inundation during high tides under the “commit to manage” sea level rise scenario. Inundation would be likely for approximately 2 to 3 hours during high tide with flood depths up to 0.8 ft.
Click the button below to see this scenario during a 100-yr coastal storm in 2050:
Present Day Coastal Storm Conditions
For present day sea levels, approximately 650 ft of Washington Street north of the intersection with Hunt Street would likely experience flood inundation during a combined 100-yr coastal storm and riverine event. The peak water surface elevation for the storm event would be approximately 8.4 ft, which would inundate the road by up to 2.9 ft for around 5 to 6 hours at the peak of the storm.
There are approximately 7 buildings located along this stretch of Washington Street north of Hunt Street which would be likely to be inaccessible during periods of inundation. These buildings may also have basements that may be flooded.
If this section of the road becomes impassible due to flood inundation, occupants within these buildings would likely be inaccessible to emergency vehicles and occupants themselves would not be able to evacuate using Washington Street. Washington Street would still be accessible from the north via Marshall Street and from the south via Robinson Street.
Click the button below to see this scenario during a 100-yr coastal storm with 4 ft of sea level rise in 2100:
2100 Average Conditions under 4 ft of Sea Level Rise
Varney Mill Road would be likely to experience flooding during high tide by 2100 under the “commit to manage” sea level rise estimate. Under this scenario, inundation up to 1.0 ft for approximately 2 to 3 hours during high tide would be likely to occur.
There are approximately 45 buildings for which Varney Mill Road is the sole access, 14 of which stem from Butler Head Road. If Butler Head Road becomes impassible due to flood inundation, the 14 buildings located along the road would be inaccessible to emergency vehicles and building occupants themselves would not be able to evacuate using Butler Head Road.
If Varney Mill Road near the intersection of Butler Head Road becomes impassible due to flood inundation, the 45 buildings, including the 14 along Butler Head Road, would be inaccessible to emergency vehicles and building occupants themselves would not be able to evacuate using Varney Mill Road. There are no alternate routes available to these areas.
Present Day Coastal Storm Conditions
For present day water levels, approximately 230 ft of North Bath Road, east of Varney Mill Road, would likely experience inundation during a combined 100-yr coastal storm and riverine event. The peak water surface elevation for the combined storm event would be approximately 9.0 ft, which would inundate the road by up to 1.6 ft for approximately 5-6 hours. The road would likely be inundated during high tides leading up to and following the peak high tide.
By 2100, approximately 20 ft of North Bath Road would be likely at risk of flood inundation during high tides under the “commit to manage” sea level rise scenario. Inundation of up to 0.9 ft would be likely for approximately 3 to 4 hours during high tide.
Click the button below to see what water levels could like on a sunny day with 4 ft of sea level rise in 2100:
Present Day Coastal Storm Conditions
For present day sea levels, approximately 342 ft of Hawkes Lane (a private road) near the intersection with Ridge Road would likely experience flood inundation during a combined 100-yr coastal storm and riverine event. The peak water surface elevation for the combined storm event would be approximately 7.5 ft, which would inundate the road by up to 1.0 ft for approximately 7 to 8 hours during the peak of the storm.
The road would likely be inundated during high tides leading up to and following the peak high tide. Ridge Road would not likely experience flood inundation in the near-term for the flood scenarios included as part of this study.
For the “prepare to manage” sea level rise scenario and a combined 100-yr coastal storm and riverine event, Hawkes Lane would likely be inundated by up to 5.6 ft and Ridge Road would likely be inundated by up to 4.6 ft. The roads would likely be inundated during high tides leading up to and following the peak high tide.
Click the button below to see this scenario during a 100-yr coastal storm with 3 ft of sea level rise in 2050:
Flood Scenarios
Fifteen flood scenarios were developed to evaluate the flood risk in the City of Bath. The scenarios incorporated estimates for present-day conditions, estimated 2050 conditions, and estimated 2100 conditions. For each timeframe, three combinations of tidal and streamflow events were used: average daily tides and average riverine flows, 100-yr coastal storm tides and average daily river flows, and 100-yr coastal storm tides combined with 100-yr riverine flows. For the 2050 and 2100 time horizons, two scenarios of sea level rise were included in order to estimate flood risk under both the “commit to manage” and “prepare to manage” sea level rise scenario.
Scroll below to select different flood scenarios map to zoom in and around Bath to explore different time horizons and the impacts of flood events.
Key for each map scenario under certain time frames and conditions
Click on each item below to visualize certain flood and sea level rise (SLR) scenarios on this interactive map:
About the Project
The City of Bath is taking measures to build community resilience to future flood events. To stay up to date on projects and events, visit the town's coastal flooding website .
The Vulnerability Assessment is one of those projects. This website is just a highlight of that work. Click HERE to view the full report.
Get engaged! Bath is developing a climate action plan and needs your input. The Resilient Bath Climate Action Plan will lay out smart, practical strategies to reduce planet-warming climate pollution (greenhouse gas emissions) and building resilience to the climate change impacts that most affect Bath residents, such as extreme precipitation, increased coastal flooding, and heat waves. Downtown Bath is one of the places that will be most affected by increased flooding due to sea level rise and storm surge.
