Georgia's Beaches: Who Owns Them? Who Cares? - 2007-05-02
Interviewer: Liz Conroy
Interviewee: David Dallmeyer
First published in The Flagpole, Athens, Georgia, May 2, 2007.
The fate of Georgia’s coast has been in the political spotlight recently like never before. The final hours of this year’s legislative session at the Georgia General Assembly (now over, but for the special session to work out the state budget) saw a bill about development on Jekyll Island making its way to a difficult compromise that will preserve the island’s undeveloped south end for now. (If you missed it, you can read about some of the details on that story in last week’s Capitol Impact column.) And although they’ve temporarily faded from view, threats to Georgia’s marshes were in the headlines just a few months ago, too. The natural environments of the coastal salt marshes, barrier islands and beaches are far more intact in Georgia than anywhere else on the East Coast, thanks to a variety of protections that have so far stood the test of time.
Professor David Dallmeyer is a UGA geologist who often takes large groups of students to the coast for education in the field. His groups often explore the still-natural beaches of Jekyll Island. We recently had a chance to ask Dallmeyer some questions about the Georgia coast.
Liz Conroy: Why should anyone who lives in Athens be concerned with coastal issues?
David Dallmeyer: The coast belongs to everyone. It doesn’t just belong to the people who live there. It doesn’t just belong to developers. The coast belongs to every single citizen. Everything below “mean high tide” is held in public trust by the state of Georgia for every single citizen. You own the beach, and have every right to be there.
As a citizen, I’m interested in maintaining the wild places on the Georgia coast because they’re mine. I’m a great believer in inter-generational equity. I want to leave behind for future generations some of those wild places that are so wonderful. Why should you care what happens to the coast? It’s a great resource, a great recreational resource.
The coast is also ecologically very important. The salt marshes, themselves, are the single most important element of the Georgia coast. They filter out pollution and sediments. The marshes serve as a nursery for many species.
Liz Conroy: What current laws govern the Georgia coast?
David Dallmeyer: The concept of public ownership of the Georgia coast is based upon the concept of the Public Trust Doctrine. This is a legal concept that dates back to Roman times. It’s come into the United States through British Common Law. The Public Trust Doctrine says that the state “holds in trust for all” certain aspects of public properties for the use of all, for the ownership of all. It’s a fundamental right that all of us have.
As for laws that govern our coasts, federal laws include the Coastal Zone Management Act and the Coastal Barrier Resources Act. But the most important state laws that govern the Georgia coast are the Coastal Marshlands Protection Act and the Shore Protection Act. These are unique and farsighted laws - especially compared to nearby states - that have gone a long way in keeping the Georgia coast pristine.
The Shore Protection Act states that the state of Georgia owns everything from the average of the highest spring tide downward. So that is where the Public Trust Doctrine comes in. Everything below the highest spring tides belongs to the state. No property owner can keep people off that. It’s your beach.
The Shore Protection Act also states that everything above the spring high tide is owned by private sectors. However, what’s unique is that the law defines something called “the dynamic dune field.” It is important to protect the dunes which serve as the first line of defense against hurricanes and storm waves.
So Georgia is quite unique, because they say that “Yes: the dynamic dune field extends from the average of the spring high tides up to the first [live] native tree that’s at least twenty feet tall or a structure that was there on July 1, 1979.” This area is owned by the private sector, but to do anything in it, you need a permit from the Georgia Department of Natural Resources. Things like building a boardwalk, a gazebo. Although you own the property, you have to get a permit to do anything in it. So this has tremendously helped stabilize the fragile coastal dune system.
The other law, the Coastal Marshlands Protection Act, works on the other side of the barrier islands protecting the marsh. The law is quite straightforward. Basically, it says that nothing can be done to alter the marsh. And, the marsh is very clearly defined as anything 5.6 feet above [and below mean high] tide… Anything that goes on within the marsh, again, has to be permitted by Georgia Department of Natural Resources.
Liz Conroy: What are the natural processes on the Georgia coast and how have people influenced them?
David Dallmeyer: Well, the beach is the most, or at least one of the most, dynamic places on our planet. You can sit there and watch it change with every variation in wind, tides, waves, currents. Nothing is constant about a beach except change.
There are many processes that affect the coast: wind, currents, waves. And, the Georgia coast is unique because it’s a tide-dominated coast. This is what gives Georgia its unique shape and number of barrier islands. Georgia has the highest tides south of Maine. They focus right down both north and south of the Georgia bight - this large re-entrant in the east coast of the United States. They focus down the Carolinas’ coasts. They focus up the Florida coast and impact directly on Georgia.
There can be up to an 11-vertical-feet change in the tides every day - twice a day. I’ve calculated that almost two trillion gallons are exchanged in the tidal cycles. That water comes through the sounds and inlets between the barrier islands, floods the salt marsh, and then six hours later, heads back out to sea. That tremendous shift of water is what gives Georgia coast its appearance.
Waves are also important. Waves generally are dominated by our wind patterns, which are out of the northeast. And so, waves tend to approach the Georgia coast at an angle, up onto the beach to the southwest, carrying sediment up which then washes down the beach after the wave energy is expended.
This creates what’s called a “long shore drift.” If you’re a little, tiny sand grain, and you start the morning on the north end of the beach, as these waves come up and “zigzag” you down the beach, you move. And you will end up at the end of the day further south. This is a very important process on Georgia beaches. Sand tends to move from north to south along the beaches.
And one negative aspect that people have done is to try to interrupt that normal sand flow by building groins. These are massive structures built perpendicular to the coast in an effort to trap sand and keep it in front of people’s property.
That works, but the downside is, those people living below the groin, south of the groin, their beach will be “starved.” So what will their response be? They’ll build another groin. So in a few years, you’ll have a whole field of groins that are cosmetically unappealing and damaging the natural sand flow.
Another thing that people do is build sea walls. These are structures built parallel to the beach. And, these structures are not built to protect the beach. They’re built to protect the property behind the beach. So the wave energy that comes into a sea wall bounces directly back down in the surf zone, causing more extensive erosion, and you lose the beach. All you have to do is look at an area that’s got a sea wall, and what you’ll find is that there’s usually no sand beach.
Liz Conroy: How will the coast of Georgia be affected as sea level rises due to global warming?
David Dallmeyer: There’s no doubt that the Earth is getting warmer. That’s a proven fact. The question really is, what’s causing it? Earth has gone through many cycles of global warming and global cooling over the last two million years. Major global glacial events have occurred in a very regular sequence on about a 100,000-year cycle. And, of course, as you make ice, build up glaciers, that water comes from the sea and sea level drops. As Earth gets warmer, as the ice melts, as the sea water expands because it’s warmer, sea level rises. So this rise and fall of sea level has been a natural process; 125,000 years ago was the last major interglacial period. At that time, most of the low-latitude ice on the planet had melted, and sea level was 200 vertical feet higher than today. Then we dropped into two major global glaciations. The last one culminated approximately 20,000 years ago. All that ice had drawn sea level down about 350 vertical feet lower than today.
So, if you wanted to go to the beach 20,000 years ago, you’d have had to have driven an extra 100 miles further east. And, then as Earth has warmed over the last 20,000 years, sea level has slowly risen and continues to do so today at the rate of between two and three millimeters per year. That doesn’t sound like much, but that’s nine inches a century. And, those are nine vertical inches over a very gentle-sloping Georgia coast.
Sea level rise is not an academic whimsy. It’s a proven fact. You can’t stop it. But people try to by building sea walls and other retentive structures. The only way to really live with a rising sea level is to live in a situation where you’re mobile, where you can move and relocate. Trying to fight it, you will only lose.
Liz Conroy: In terms of our beaches, what would you like people in Georgia do?
David Dallmeyer: Everybody in Georgia, as an owner of the beach, as a taxpayer, as a voter, needs to be educated. To me, this is the key.
I don’t think the average citizen really wants to damage the coast. I just don’t think that they understand the impacts of what they can do. Many times they’re doing things, even in good faith, but they have tremendously negative results on the natural system.
The scale of coastal processes is so enormous; we need to appreciate that. When you look at that sand beach - the “recreational” beach - you’re looking at a very tiny fraction of the entire sand budget that’s there. Most of the sand is offshore, and there’s an exchange between offshore and onshore sand depending upon weather conditions. It’s difficult to conceive of the enormous nature of the system by just what you see above the water.
I think you need to be educated about these processes of long shore drift, sea level rise, and the long-term implications of trying to deal with these. I think if you’re going to live at the coast, you have a responsibility to understand those processes and live by the rules of the sea, not at combat with the sea.
Liz Conroy: What is your favorite beach to roam?
David Dallmeyer: In Georgia? Well, the Georgia coast is characterized by somewhere between 13 and 15 barrier islands depending upon how big you want to count ‘em. And there’s only three causeways: one goes to Tybee Island, one goes over to St. Simon's and Sea Island, and the other is the causeway to Jekyll Island.
Jekyll, being a state park, is the least developed of those islands accessible by a causeway. So, for me, the wildest place on the Georgia coast, that you can get to easily without a water craft, is the southern coast of Jekyll. Walk 10 minutes from the parking area and you’ll be at the end of the world on one of the most beautiful beaches that I’ve ever seen.