We used to live on Hilton Head Island, along the Intracoastal Water Way. Our house was on one of the highest points of the entire island. 12 feet above sea level.
When you look at a flood map, the ENTIRE island is a flood zone. Yet, many of the people who live there don’t quite understand what that means. They also don’t understand storm surge. A friend who had a beautiful house on the Atlantic side, facing that wonderful beach. We were talking about it one day and she really thought an eight foot storm surge meant that the water would come eight feet closer to her house along the beach horizontally than normal.
We had a 240 foot long walkway with a floating dock at the end. Depending on the tides, there were times when the metal gangplank to that dock was almost horizontal at a high-high tide and almost vertical at a low-low. That was another aspect many who don’t know tides and currents aren’t aware of. Not all tides are the same. Some are more extreme.
I learned about the power of water and tide and current when commanding a Maritime Operations A-Team in Special Forces. When we training up to go to Denmark to attend Combat Swim School, we camped out on an island off the coast of Maine. One day, to teach us the power of tide and current, my team sergeant, who was scuba qualified, had us swim toward the mouth of a river. Going against both. We wore dry suit and swam on our back, finning hard.. Yet we were pushed out to sea despite efforts.
The bottom line? Storm surge is vertical height. The water being pushed by Hurricane Dorian, even if it is out at sea, will be massive. When combined with an incoming tide, this can be deadly.
Evacuate if so ordered. It’s not as much about the wind. It’s about the water.
Here is more information on storm surge and flooding and the power of water:
Originally published at https://bobmayer.com.