Leatherman

Storm-Generated Overwash Processes at Assateague Island,

Stephen P. Leatherman*

Department of Earth & Environment, Florida International University, Miami, FL, USA

My dissertation research at the University of (UVa) involved taking the first field measurements of storm-generated overwash processes (Leatherman, 1979; Leatherman, Fisher, and Williams, 1977; Leatherman and Williams, 1977). This required driving a great distance from the foothills of the Appalachian Mountains in Charlottesville, Virginia, to the Maryland Atlantic coast.

During the three years of measurements (1972-1975) at the northern end of Assateague Island National Seashore, most of the storm events occurred during winter nor’easters, which meant it was very cold, windy and rainy/snowy/sleeting. I was able to obtain a surplus World War II, 6- wheel drive welding truck to use as my field vehicle (Figure 1). This rugged vehicle climbed up and over the 1.3 meter-high, wave-cut beach scarp without any difficulty.

Figure 1. The six-wheel drive field vehicle, Assateague Island. (Photo: S.P. Leatherman.) For the first year, I used a hand-held Gurley current meter that had a propeller at the end of a shaft wherein I stood in the gap in the dunes where the overwash water and entrained sediment surged through during the height of the storm. I donned armpit high waders, but one large surge

DO I:10.2112/JCR-SI101-011.1 *Corresponding author: [email protected] ©Coastal Education and Research Foundation, Inc. 2020 48 Journal of Coastal Research, Special Issue No. 101, 2020 knocked me down and swept me landward in the icy cold water on my back, still grasping the current meter. My major professor John Fisher came on this trip, knowing that it was going to be a big event, and videotaped the overwash surges from the top of the sand dune (safe and dry). He thought it was quite amusing that I was engulfed in the surging water; I quickly shed the freezing wet clothes as the storm continued to rage. Figure 2 shows an overwash surge passing through the dunes.

Figure 2. Overwash during a nor’easter, Assateague Island. (Photo: S.P. Leatherman.)

Most times I would take undergraduate students with me as field assistants, but they did not want to return for a second time, requiring a lot of recruiting. One problem was that it was miserably cold, and we camped out as this was not a funded research project. Sometimes we would find our sleeping bags floating on air mattresses in the water-filled tent; wherein, we would sleep in the back of the Army truck, which was at least dry.

When the big waves broke, hitting the 4-meter high dunes, it was a bit terrifying to the new recruits. Of course, it did not help when I would sometimes tie a rope to the bumper of the big old Army truck and another around their waists. They would ask why I did this to which I answered, ‘So at least I can recover the body!’ For some reason no one ever laughed at my joke. This work was somewhat dangerous but definitely exhilarating – I certainly never want to do any more winter camping.

I took a few trips to Assateague Island during the non-storm season to monitor my aeolian sand traps (Leatherman, 1978), which were used to determine where the sand was blowing off the unvegetated washover fan. Some graduate students in the Department of Environmental Sciences wanted to come down to the beach during the early fall when the water was still warm and before the onset of winter nor’easters. I was able to obtain permission for twenty of us to camp at Assateague Island State Park (AISP), which had proper campsites, including bathrooms with hot-

49 Leatherman water showers, potable water for drinking, grills and picnic tables. Unfortunately, AISP was closed during the off-season, so unavailable during my strenuous winter research work.

One couple brought a lot of food from home including a chocolate cake, which they mistakenly left on the picnic table unbeknownst to me. At about 3 AM, a small herd of the indigenous (which are believed to have swum ashore from a Spanish shipwreck during the 1700s) arrived in the camp area (Figure 3). Food is sparse on this barrier island, and the ponies are fairly small and relatively tame, albeit they can bite and kick, being wild animals. Unfortunately, one of the ponies ate the entire chocolate cake and then became sick, producing the loudest, vilest noise I have ever heard – belching out its stomach contents straight into the open tent. This commotion was quickly followed by the shrieks from the guy and gal who were covered with vomit. They ran to the showers, cleaned up and left that night. I had to take down their tainted tent and throw it in the dumpster as no one wanted it.

Figure 3. Assateague Island . (Photo: S.P. Leatherman.)

LITERATURE CITED Leatherman, S.P., 1978. A new aeolian sand trap design. Sedimentology, 25, 303-306.

Leatherman, S.P., 1979. Migration of Assateague Island, Maryland, by inlet and overwash processes. Geology, 7, 104-107.

Leatherman, S.P. and Williams, A.T., 1977. Lateral textural grading in overwash sediments. Earth Surface Processes, 2, 333-341.

Leatherman, S.P.; Williams, A.T., and Fisher, J.S., 1977. Overwash sedimentation associated with a large-scale Northeaster. Marine Geology, 24, 109-121.

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