The Maine Geological Survey is leading a King Tides initiative to document and map the effect that extreme tide events have on the state’s beaches, coastal bays and estuaries, and public infrastructure. Past storms that have arrived during King Tides have caused severe beach and dune erosion as well as property damage. Over time, the reach and effect of King Tide events may increase due to gradual mean sea level rise. Identifying the areas of tidal influence today will help prepare for future coastal hazards.
The term “King Tide” is a non-scientific term used to describe the highest seasonal tides that occur each year. These tides occur naturally and are typically caused when a spring tide (when the sun, moon, and earth align during a new and full moon, increasing tide ranges) takes place when the moon is closest to Earth during the 28-day elliptical orbit (known as a perigee). The highest astronomical tide in Maine can range 2 to 4 feet above mean high water at locations along the coast. To learn more, visit the MGS website.
The effect of individual King Tides may vary considerably. In some cases, they may barely even be noticed. In other cases, a King Tide may cause coastal erosion, flooding of low-lying areas, and disruption to normal daily routines. This is particularly true when a King Tide event coincides with significant precipitation because fresh water drainage and runoff through storms drains may be impeded by salt water.
Help Document King Tides in Maine
You can help document King Tides by submitting images to this site and by participating in the Gulf of Maine King Tides Photo Contest held each fall. Images submitted to this site and to the contest may be used for educational purposes.
Tips for Effective King Tides Photos
- Take pictures at or near peak high tide.
- Take pictures where the impact of the tide can be gauged against familiar landmarks like buildings, roads, sidewalks, parking lots, jetties, bridges, sea walls, shorelines, or bulkheads.
- Taking contrasting shots of peak high and peak low tides helps to show the tidal variability.
- Be Safe! Use good judgment when you are taking your photos. Stay away from dangerous situations particularly in stormy conditions and avoid taking risks.