5-11-06

A Commentary on "Beach Nourishment: A Starvation Diet"


Last year Florida spent $180 million to "nourish" its beaches with most of the fill sand mined from the nearshore (as is most of all our beach nourishment fill). Earlier that year, Barry Drucker, the Minerals Management Service scientist responsible for studying the offshore sand mining process used for nourishment, wrote to me stating that, as dredging operations become more efficient, offshore sand mining was moving towards deep waters (which, in many areas of the US, means many miles offshore). More importantly, he continues, "Some of this shift is definitely due to the realization that exploiting too much of deposit in close proximity to the beach can actually have a devastating effect on the shoreline and subsequent increases in erosion."

This means the erosion caused by this is ongoing as those once protective shoals are now obliterated by this earlier mining. What he does not say, and what is becoming painfully evident in areas such as Florida and our Gulf coast, is that much of our easily exploitable nearshore shoals have already been mined so that the move to mine deep water deposits are now required. This means more expense, a spreading destruction of the seabed habitat and further harm to onshore and nearshore ecosystems. It also means that our nearshores are deepening and steepening allowing more destructive storm energy to reach the shoreline.

By allowing our coastlines to be controlled by the dredging industry, its coastal engineering consultants and lobbyists and often uninformed officials, we are losing these and the coastal habitats these sustain. We do have alternative proven to be sustainable and environmentally sound. Given the known hazards and escalating costs of nourishment programs, it would seem environmental organizations, governmental agencies and local citizens impacted by such counterproductive (though often officially sanctioned) programs would wish to research and promote such fiscally and physically sustainable alternatives.


Below is my earlier essay on this process:


"Beach Nourishment: A Starvation Diet"
(as sent in response to Dr. James Leutze's article in Raleigh's Metro Magazine, July 2004 and published in its September, 2004 issued)


While Dr. Luetze is correct on the economic importance of maintaining our shorelines, he seems to be uninformed of the true costs of constant dredging and renourishment projects.

The term beach "nourishment", carefully chosen to sound healthy, is really a starvation diet. The research and empirical data continues to demonstrate its environmental damage to coastal ecosystems as well as it leading to increased erosion. The dredging of inlets and offshore shoals for sand fill increases onshore erosion according to the EU's 2004 "Guide to Coastal Erosion Management". It further states this causes sediment starvation and hydraulic changes inducing even more erosion. Our own reports, including those of the Corps, bear this out. In 2000, a research abstract for the Minerals Management Service stated, "When a shoal is flattened (by dredging), the degree of wave energy concentration is likely to be reduced, resulting in greater wave energies hitting the coastal area. This may result in increased coastal erosion or unwanted, detrimental changes in longshore or nearshore current patterns. Significant coastal impacts could also be expected during storm events in that increased wave energies which might have been somewhat dissipated by the presence of the shoal would now impact the coastal area with greater forces." Research done by the NC Geological Society and the University of Arkansas off Pea Island in 2000 directly related offshore shoal topography to erosion hot spots. Up to three miles offshore (the farthest area studied), the shoal topography still effected onshore erosion. Shoals much nearer to shore are the major sand source for nourishment mining and, consequently, can have a more direct impact.

Manmade erosion is a fact. From dams, to the ever-deeper dredging of channels and inlets, to offshore strip-mining of shoals for sand fill, to sea level rise from global warming, we are the cause of much of this accelerating problem. While onshore overdevelopment is a problem, it does not directly cause more erosion. It is what we do in the water that causes the problems. Only when we apply traditionally engineered shore protection (groins, seawalls, jetties, etc.) to protect these does this development directly impact erosion trends --and these are upward.

Erosion rates have accelerated over the last 10 years in NC even as NC officially embraces Dr. Pilkey's irrational suppositions that erosion is natural and retreat is a viable environmental option. As in reality, much of this erosion is manmade, we must mitigate this as we would any other manmade environmental problem. Applying methods we know --especially by the so called experts in the Corps, coastal consultant and dredging industries-- to be counterproductive, only enriches these groups while impoverishing our coastal ecosystems and the taxpayer.

We are talking about habitat, not real estate. We are also losing habitat at an accelerating rates. Even our coastal fresh water supplies are now at risk. This can only lead to catastrophic collapse of our coastal systems as is happening in Louisiana, our coastal canary. More traditional coastal industries linked to sealife --fishing, shrimping, crabbing, etc.-- are likely to suffer as our coastal estuaries as the Pamlico Sound, continue to be overwashed by sea water destroying the fragile saline balance needed for such sealife nurseries. Thanks to the recent super-deep dredging for the Wilmington harbor and channel, salt water now projects almost twice as far --twenty miles-- inland than it did a few years ago. If we lose the Outer Banks, the Pamlico Sound becomes the high energy Pamilco Bay and we have lost the second largest estuary system in the US. The constant dredging of the Oregon Inlet, other inlets, ferry crossings, the Intracoastal Waterway, and previous nourishments induces further erosion both to the ocean and sound sides of barrier islands. This is not nature taking its course, this is murder by a thousand cuts. Yet, coastal real estate is a vital economic activity for our coastal communities. We have to acknowledge the great importance real estate and tourism are to our coastal economies and that this is based on having wide, safe beaches

The dredging lobbyist Howard Marlowe, his coastal consultant associates and such aligned dredging lobbying groups as his American Shore and Beach Preservation Association (and its many linked groups) prey on these desperate communities. These groups to seem control our coastal policies and practices even though dredging actually causes more erosion and other cumulative damage to our coastal environments. These groups' overly close relationship with the Corps has made it the chief agent of erosion on our shorelines.

The successful promotion of beach nourishment in Florida means many of its areas are now literally out of sand. Broward County is now experimenting with ground glass as beach fill having exhausted his available offshore sand sources. It beach manager, by the way, is Steve Higgins, a board member of the American Shore and Beach Preservation Association (ASBPA), the major beach nourishment lobbying group. This should make us all wary of promises by the Corps of 50-year nourishment programs.

There are also health risks in dumping dredged sediments onto beaches. In 2001, the Office of Naval Research warned of dredging tainted sediments because, "In harbors, waterfronts and shorelines around the world, sediments that have been contaminated by even small amounts of oil, chemicals or other pollutants may pose a risk to humans and to natural ecosystems." Even so, these are often promoted as beach fill by the Corps through its desperate attempts to insure the success of its "beneficial use" disposal methods. In 2000, the Corps sought to dump dredgings tainted with asbestos and other industrial wastes from the Waukegan Harbor onto Illinois Beach State Park as "renourishment" to dispose of these while fulfilling its requirement to mitigate erosion its caused by its other channel dredging.

The grinding of the sand itself as it moves through the dredger and piping produces silt, a pollutant in itself. These finds smother reefs and other seabed and nearshore habitats. This also helps deplete the very resource being mined.

Another characteristic often found on recently renourished beaches: rip currents. These potentially deadly (several people drowned near Pensacola, FL this past year) currents form as the steep profile of the unnatural beach is moved into toughs along the nearshore. One lifeguard in Savannah says they know after each nourishment to expect this.

We are losing our shorelines and the coastal resources these protect. Almost all of this lost is directly attributable to man. We can help mitigate this damage with methods proven to be sustainable and environmentally sound. Unfortunately for our coastlines and our taxpayers, beach nourishment is not one of these.

Jerry Berne
Sustainable Shorelines, Inc. (www.sustainableshorelines.org)

Sustainable Shorelines is a nonprofit corporation dedicated to documenting current environmental events on our shorelines, identifying and seeking to change those coastal policies and practices which are harmful and advocating protecting our coastal habitats and the ecosystems these support with methods proven to be environmentally sound and sustainable.