Atlantic Coast at Portland (IN MLLW)
Maine — Water Level & Flood Stage
Located in Cumberland County, Maine on the Atlantic Coast. Live water level data from USGS, updated every 15 minutes.
Current Water Level
Gage Height
Loading...
Streamflow
Loading...
Last Reading
Loading...
This is an NWS forecast point (LID: CASM1). Live data may be limited. View on NWS AHPS →
Flood Stages
Major Flood
14 ft
Moderate Flood
13 ft
Minor Flood
12 ft
Action Stage
10.5 ft
Flood stages defined by the National Weather Service. Gage height data from USGS Water Resources.
What Floods at Each Level
13.8 ft
Water will enter and flood businesses along and near the Portland Pier. Water will be nearly two feet deep along Granite Point Road in Biddeford and Mile Stretch Road will be flooded. Roads and businesses will also flood in Wells and Kennebunkport.
13 ft
Water will reach the tailpipes of cars at businesses near the Portland Pier. At this elevation, a foot of water will also cover Granite Point Road in Biddeford
12.5 ft
Water will be eight to ten inches deep along several low lying side streets and wharfs along Portland Harbor with water up to the bottom of doors in parking lots east of the Portland Peir. Water will be eight to 10 inches deep covering Marginal Way in Portland with six to eight inches of water on Somserset Street.
12 ft
Flooding four to six inches deep occurs along the wharfs and most vulnerable side streets near the Portland Pier. Coastal flooding begins on Marginal Way and Somerset Street, especially if combined with heavy rainfall.
Impact statements from the National Weather Service, describing what typically happens at each water level.
7-Day Water Level Chart
Loading chart data...
Historic Crests
| Date | Stage | Flow |
|---|---|---|
| Jan 13, 2024 | 14.57 ft | — |
| Jan 13, 2024 | 14.57 ft | — |
| Feb 6, 1978 | 14.17 ft | — |
| Feb 6, 1978 | 14.17 ft | — |
| Jan 8, 1978 | 13.98 ft | — |
About This Gauge
NWS LID
CASM1
River
Atlantic Coast
County
Cumberland, ME
Coordinates
43.6567°N, 70.2467°W
Get Flood Alerts for Atlantic Coast
StormCast monitors this gauge and sends a push notification to your phone when the water level crosses into a new flood category — even at 3 AM.
Frequently Asked Questions
What is the current water level of Atlantic Coast at Portland (IN MLLW)?
The Atlantic Coast at Portland (IN MLLW) gauge is maintained by USGS and reports water levels every 15 minutes. Visit this page to see the latest reading updated live, or download StormCast to get push alerts when levels rise.
What is flood stage for Atlantic Coast at Portland (IN MLLW)?
The NWS-defined flood stage for Atlantic Coast at Portland (IN MLLW) is 12 feet. Action stage begins at 10.5 feet. Moderate flooding starts at 13 feet, and major flooding at 14 feet.
How do I get alerts when Atlantic Coast rises?
Download StormCast free on Google Play, go to River Gauges, and add Atlantic Coast at Portland (IN MLLW) to your watchlist. StormCast will send a push notification to your phone whenever the water level crosses into a new NWS flood category — even when your screen is off.
Where is the Atlantic Coast at Portland (IN MLLW) gauge located?
The gauge is located in Cumberland County, Maine at coordinates 43.6567°N, 70.2467°W. Data is provided by the U.S. Geological Survey and the National Weather Service.
More Gauges on Atlantic Coast
More Resources
Source & Notes
- Please refer to our <style type="text/css"> .style1 {background-color: #FFFF00;}</style> <a href="http://forecast.weather.gov/product.php?site=NWS&issuedby=GYX&product=CFW&format=CI&version=1&glossary=0"> <span class="style1">Coastal Hazard Message</span></a> for specific information regarding Coastal Flood Watches, Warnings and Advisories. During tropical cyclones, please refer<a href="https://forecast.weather.gov/product.php?site=NWS&issuedby=GYX&product=TCV&format=CI&version=1&glossary=1"><span class="style1"> here</span></a> for additional storm surge information.
- Coastal flood impacts are dependent upon waves as well as tide level. High waves can result in flooding even if the tide level is below flood stage.