We’re about 13 feet above sea level and around 15 miles from the nearest beach. This is the “Lowcountry,” though, and there’s a tidal estuary about 3 miles from us and a flood plain with a small river less than a half mile west. The NOAA flood maps suggested that a category 2 storm could under the worst conditions push a 3-6 foot storm surge up that river and towards us.
I was up early Saturday morning and glued to Weather Underground as the north side of Matthew’s eyewall brushed past Calibogue Sound, one of the primary avenues for drainage in our area, right at high tide.
We certainly weren’t anywhere nearly as badly hit as Hilton Head Island, where the county is just now beginning to let people back in, but we were only maybe 18″ of water level away from water coming into the houses here.
Storm surge or rain? The bag marks the high water line (click for gallery view). The
flood plain with its small river — generally a small creek — is less than .5 miles to the right. It turns out from examining debris lines around the pond between us and the river that the flooding was from the community drainage system, which got overwhelmed by 11.5 inches of rain. I don’t know whether the surge also came up into the flood plain or how high it might have reached. Fortunately, not to us.
[Note: The ponds, or “lagoons” as the real estate people call them, is part of our drainage system. Water from the streets and yards drains into the ponds, which then overflow into the flood plain. There’s a grating at the bottom of the small pool that is supposed to feel runoff into the pond. As you can see, it’s having a few problems. In a storm surge, water would be coming up the other way, from the flood plain and then over the banks of the pond and towards us.]