An Education at Sea Level
ABOVE: "An Education at Sea Level" was the cover story of the Fall 1997 issue of Coastal Magazine
An Education at Sea Level
By the end of 1998, more than 5.1 million cubic yards of sand will have been pumped from the ocean floor to beachfronts along the Grand Stand as part of a two-year $54 million beach renourishment project. Most experts now agree that renourishment is the best modus operandi for preserving our beaches – and hence the economic stability of the region. Coastal Carolina University's Center for Marine and Wetland Studies, the outreach program of the School of Natural and Applied Sciences, has a big say in where it all ends up on shore. Under the direction of Paul Gayes, professor of marine science at Coastal, the center is conducting a number of cutting-edge marine geological studies which are vital to the environment and important to the field at large. In the process, Coastal's marine science students are getting some of the best instruction and experience offered by any undergraduate institution in the country.
Every semester, Gayes and a group of about 20 marine science students spend up to two weeks aboard the Ferrel, a research vessel of the National Oceanic and Atmospheric Agency (NOAA), where essential data for several important studies is gathered. This 153-foot cybership was anchored off Myrtle Beach, not far from one of the sand dredging rigs, the day that Gayes invited us (a group of reporters and me) to come aboard and observe what he and the students were working on.
We were ferried out to the Ferrel on the Department of Marine Science research boat, the 43-foot Coastal II, which Professor Rob Young and a group of students were using that day for the dolphin count, an ongoing project which monitors dolphin population trends between Georgetown and Little River. Leaving from Marsh Harbour Marina at Calabash, Coastal II cruised by Waites Island, part of which has been donated to Coastal for reasearch and preservation, and into the Atlantic via Little River Inlet. As the water was a little rough, Young called off the dolphin count; still, we saw a few gleaming fins arc the surface in the distance on the journey to the Ferrel.
Rough water also promised to make our transfer from the Coastal II to the Ferrel a little tricky. We were to jump ship, literally stepping from deck to deck as the Coastal II sidled up alongside the larger ship. This is simple enough to accomplish in calm water, Young told us, but in high seas the boats can butt violently against each other, endangering the vessels, particularly the smaller Coastal II, not to mention the passengers en route from one to the other. Luckily, the sea was calmer by the time we reached the Ferrel, although we had to make several separate approaches before we finally made it aboard.
Professor Gayes was waiting to welcome us. Anticipating our wobbly sea legs, he first helped us to locate certain necessary facilities and pointed out one of the Ferrel's memorable features: on the port side of the main deck, in a conveniently out-of-the-way spot, painted footprints with corresponding handprints on the railing invite seasick passengers to express their misery. "The Ferrel has a shallow bottom and seasickness is very common," said Gayes. "This is the spot everyone seemed drawn to, so they painted the hand and footprints to make it official. Despite all the time I spend out here, I get a little green sometimes, and when I do I am not happy." His admission was reassuring, as some of us were already in a queasy state of denial.
Gayes is tall and soft-spoken, but he is a lightning-fast talker; the verbal deluge attests to his passion for what he is doing and to the fact that he is a busy man. He earned his Ph.D. in coastal oceanography from the Marine Sciences Research Center at the State University of New York Stony Brook. Gayes joined the Coastal faculty in 1987 and had directed the Center since 1989. He published numerous scholarly papers on coastal geology and he serves on the UNESCO International Geologic Correlation Program, a panel charged to study sea level changes.
The Ferrel costs up to $10,000 a day to operate, Gayes told us. "Ship time is awarded competitively on a national basis through the National Sea Grant program. We've been getting about 20 to 30 days a year for the past five years, which is more than any other undergraduate institution in the country," he said. "They had never seen undergraduates on the Ferrel until we got involved, and over the last few years we've probably had 70 to 80 Coastal students out on this vessel, which represents a significant opportunity for the university and the students."
The main reason Coastal receives a lion's share of ship time is that Gayes is the principal investigator of a number of grants, many of them devoted to research of the geological aspects of beach erosion and renourishment, that require the Ferrel's high-tech services. The Center for Marine and Wetland Studies received a total of more than $600,000 in grant monies last year. The grants are awarded by many different federal and state agencies for a variety of studies. "Even though each study has its own goal, the projects are interconnected," said Gayes. "An aspect of one project will illuminate some aspect of another project, so there's a spin-off effect. This interrelatedness often allows us to learn more, to go beyond the original intention of the grant."
One such grant, now in its fourth year, is awarded by Intermar, a division of the U.S. Department of the Interior’s Minerals Management Service. “As part of the Intermar Task Force on Beach Renourishment and Critical Habitats, we have compiled a database for the state outlining a great deal of geological information on the South Carolina continental shelf,” said Gayes. “This study takes a close look at mineral and sand resources as well as biological habitats. A major part of this project involves looking for sand resources along the state’s coast near cities which have committed to renourishment projects.” Last year, he and a group of students did an assessment of potential renourishment projects at Edisto Beach near Charleston and began a study of the Hilton Head Island area. The Intermar project dovetails nicely with other grants, such as one funded by the U.S. Army Corps of Engineers to assess renourishment projects in Myrtle Beach and Folly Beach. Another, funded by the U.S. Geological Survey and the S.C. Sea Grant Consortium, focuses on coastal erosion in the area between Edisto Island and Bull Island. Scott Harris, a Ph.D. candidate from the University of Delaware, has been working out of the Center since January as part of this project. Dozens of Coastal marine science students are working in various capacities on all of these research programs.
The deck of the Ferrel was crowded with equipment designed to perform a range of geophysical tests which turn up a wealth of information about the surface of the sea floor and what’s under it. Gayes and Matt Cline, a junior marine science major from Beckley, W.Va., who is developing an internet home page for the Center for Marine and Wetland Studies, had spent most of the previous night running a sidescan sonar. This instrument, which looks like a long silver torpedo, is hooked to cables and towed behind the ship. As the Ferrel trawls along, the sidescan sonar sends out and receives sound waves along a 200-meter swatch of ocean floor; the sound waves are translated into a series of remarkably realistic video pictures which Gayes and his students will study in detail over the coming weeks and months.
Further along the deck of the Ferrel were stacks of long metal cylinders called Vibracores, which the Center’s research specialist Neal Gielstra designed and built especially for this project. Some of the cylinders, the unused ones, were hollow. Some were packed full of silt, sand and rocks from the ocean’s subbottom and were ready to be taken back to a lab at Coastal for analysis. “This electric motor hammers the vertical Vibracore cylinders 20 to 30 feet directly into the sea floor,” said Gayes. “As the Vibracore sinks down, it collects a deep cross section of the accumulated sediments which make up the subbottom. It acts very much like a needle taking a biopsy.
Gayes showed us a used Vibracore which had been neatly split and halved. It contained dozens of discernible layers of what looked to us like various grades of plain dirt. To Gayes, however, these narrow brown and black bands of earth tell the story of the past millennium. “These dark spots here were caused by storms stirring up the bottom hundreds of years ago,” said Gayes, pointing to the darkest soils in the sample. “From these Vibracore samples we are getting an accurate record of the big storms which have hit this part of the coast during the past thousand years.” The instrument has been very useful in studying ancient submerged forests with 10,000-year-old cypress stumps which have been found 15 miles offshore in just 60 feet of water.
The Vibracore system is also used to verify or “ground truth” data gathered by the seismic reflection profiling system, which looks like a big orange sled towed behind the Ferrel on cables. The seismic reflection device sends down sound waves which penetrate some 40 meters into the ocean floor. Hydrophones in the device pick up the vibrations and turn them into electrical pulses which a computer transforms into a kind of map illustrating the layers of sediment beneath the bottom of the sea.
“One of the difficulties we faced when we began researching beach erosion and renourishment was that we didn’t have long-term data on how sediments behave – how fast they move, where they go,” said Gayes. “By analyzing the seismic reflection studies and the Vibracore samples – and this analysis is driven in large part by marine science students back in the labs at Coastal – we are getting, for the first time, a complete history of this environment. We can track annual erosion rates over the past 1,000 years. We can look at sediments and determine if they are usable for beach renourishment.”
As Gayes led us toward the interior cabins to show us the computer room, a group of men and women guided a huge, crane-hoisted wire cage, dripping seawater and full of flapping, splashing fish, onto the deck and emptied it. “These folks are from the Department of Wildlife and Marine Resources Division,” Gayes said as they began to scoop up the fish and lay them out in rows on the deck for identification. “They are doing fish trawls, putting fish traps on top of the rocky areas on the bottom, to gather detailed information on sea life habitats in areas affected by renourishment.” Their work is vital, according to Gayes, in determining fish-friendly resources for beach renourishment and in learning how the dispersal of sand after renourishment is influencing sea life environments.
In the cabin Gayes showed us the computers which make sense of all this underwater sonar and he pulled out several large printouts of data. “This area is sand,” Gayes said, pointing to a sidescan sonar map. “These are rocks, and here we can see the outline of an old shipwreck. This technology is so accurate that it can even pick out fishing poles on the sea floor.” One thing the mosaic map of the Myrtle Beach area clearly shows is that the largest sand deposits stretch out from the swashes, such as Withers Swash, perpendicularly to the coastline. “All the sand being pumped onto the beach now is coming from what were at one time channels. This is where the swashes are now.”
By studying and comparing the results of these procedures – sidescan mosaics, seismic reflection and the Vibracore samples – over a period of time, Gayes and his colleagues can see how the sand shifts, where it’s going, and how fast it’s moving. “The position of the dredged sand that is being placed on the beach,” Gayes explained as he pointed to the great metal hulk looming above the horizon, “was picked and cited based on the studies we did here on the Ferrel and on Coastal’s vessels. We basically sat down with the Corps of Engineers and the Department of Natural Resources to work out where those pipings could go ashore with minimal damage to natural habitats.”
While he and his students and colleagues have gathered an incredible amount of functional data in a relatively short amount of time (the Center for Marine and Wetland Studies was begun in 1988, and most of these studies have been in place less than six years), Gayes says that, in order to build an effective model for the entire South Carolina coast, a longer window is needed. “It was originally predicted that the Grand Strand renourishment project would require additional sand every eight years, but that is a very uncertain estimate,” said Gayes. “The existing model can’t predict the future. We need at least 10 consecutive years of steady analysis before we can predict when additional fills are needed. Some areas may not need or want to renourish.”
Last spring, students in Gayes’ marine biology class took their final exam aboard the Ferrel. “This is the great thing about our program,” he said. “By being involved first-hand in many different areas of research, students get to look at things from all sides – the geological, chemical, biological and physical aspects. They share information from each other’s projects. They see how one thing is related to everything else, and that the issues involved aren’t always black and white. They turn up a lot more questions than we have answers for, but we challenge our students to see the other side of issues. It gives them an edge that is increasingly competitive.”
The opening spread of "An Education at Sea Level" in the Fall 1997 issue of Coastal Magazine. The article was written by CCU staff memeber Doug Bell.