ReBuilt Beaches and Coastal Dunes Are Standing Strong
By Marcia Bradford, Condo Owner Magazine, Volume 18, Issue 3 (Summer 2014)
As you walk along the shoreline or drive down the coastal highway, be sure to take notice of the expansive beaches and tall sand dunes that line the Gulf Coast in Alabama and northwest Florida. Besides offering up beautiful scenery and providing recreational space, these important natural resources are essential to protecting both public infrastructure and private buildings, including beachfront condominiums, according to coastal engineers who have worked to rebuild and maintain the beaches that Hurricane Ivan struck in September 2004.
Scott Douglass, professor of coastal engineering at the University of South Alabama and owner of South Coast Engineers in Fairhope, emphasized that “healthy barrier islands and wide sandy beaches are Mother Nature’s ‘resilient infrastructure.’ They are the natural speed bump, minimizing destruction wrought by hurricane storm surge and waves.”
As such, he added, they are one of the top economic and environmental assets in coastal Alabama and northwest Florida.
Pre-Ivan Beach Conditions Set The Stage
Hurricane Ivan can be correctly blamed for causing a great deal of damage, but the poor condition of the coastline from Gulf Shores to Pensacola prior to the storm helped set the stage for the devastation that occurred in 2004, according to Phillip West, Coastal Resources Manager for the City of Orange Beach.
Now that 10 years have passed since Ivan flattened most of the dunes in the area, it might be easy to forget how eroded the beaches had become during the 1990s and early 2000s, he said.
“Many people may not realize that the beaches along this stretch of the coast were wide and had high sand dunes many years ago,” he said. “Also, they may not remember how eroded the beaches had gotten prior to Ivan. The beaches were very stressed before Ivan hit, by many smaller events, such as tropical storms and lower category hurricanes, which had caused severe damage.”
Al Browder, senior engineer and vice president of Olsen Associates, Inc. Coastal Engineering, based in Jacksonville, Fla., remembers the pre-Ivan conditions very distinctly.
“Over the decades, communities along the coast had been losing bits of their beaches every year and they were talking about restoration projects long before Ivan,” he recalled. “In 1995, Hurricanes Erin and Opal hit the area. Opal did some pretty bad damage to Gulf Shores but it really hit Pensacola hard. Then, in 1998, Hurricane Georges accelerated the damages caused by the earlier storms.”
By 2000, the first engineered beach renourishment project in the state of Alabama was underway. Fast-tracked over 18 months, the $4.1 million project placed 1.65 million cubic yards of sand along the eastern 3.1 miles of Gulf Shores. Olsen Associates prepared the feasibility study, designed the project and acquired state and federal permits.
The rebuilt beaches made a difference. In areas where the waters of the gulf had previously splashed into the lower floors of some condos and other structures, there was now a wide stretch of beach between the buildings and the shoreline. Beach re-nourishment was followed with dune vegetation and sand fencing placement.
“There were lots of high-rise condos in this area and they had been very vulnerable prior to the renourishment,” Browder said. “After renourishment they had a buffer again.”
Ivan Disrupts Progress
Olsen Associates also engineered a renourishment project in Pensacola Beach during 2002 and 2003 and was about to start on the beach areas that needed restoration in Orange Beach and Gulf State Park when Hurricane Ivan entered the Gulf of Mexico.
“We had just put the project out to bid when Ivan hit,” Browder said. “Then we had to redesign the project.”
Although Ivan caused major destruction, the massive hurricane proved the importance of nourishing the beaches. “In Pensacola Beach, for example, Ivan took out most of the sand that had been placed there in 2002 and 2003, but the damage to the entire area would have been far worse if the sand had not slowed the surge,” Browder said. “Compared to the nearby Gulf Islands National Seashore, which was closed for a long time because roads were washed away, Pensacola Beach was able to recover much faster.”
According to West, a re-designed beach renourishment in Orange Beach and at the Gulf State Park began in January 2005. More than 7.9 million cubic yards of sand were placed along the shoreline and new dunes were built with salt-tolerant vegetation and protective sand fencing. The construction cost of the project totaled $30.9 million.
“This project covered a 16-mile stretch of beach, with the goal of returning it back to the conditions of 30 years prior to the storm, which included a much wider beach and a significant line of sand dunes,” he said.
Along Comes Katrina
While Mississippi and Louisiana bore the brunt of Hurricane Katrina, Alabama and northwest Florida were also affected by the surge. Additionally, the 2005 renourishment project was further disrupted by the impacts of Tropical Storm Arlene and Hurricanes Dennis and Rita, according to Browder.
Fortunately, because the beaches were now considered “engineered beaches” and met the necessary criteria for federal funds, financial assistance from the Federal Emergency Management Agency (FEMA) helped restore the beaches after the 2005 storm damages and in 2006, the project was designated as a Top Restored Beach by the American Shore and Beach Preservation Association.
West pointed out that the storms of 2005 proved the importance of rebuilding beaches and dunes.
“Katrina brought a 10-foot storm surge to the Alabama coast, but there was hardly any structural damage caused,” he explained. “Despite many significant storm surges, the beach restoration project had definitely done its job with regard to protecting upland construction and providing some relief from insurance issues and the cost from the loss of business. By Labor Day weekend of 2005, despite Katrina and several other storms, the condos were up and running, the beaches were cleaned and the area was open for business. And it means a lot to be open rather than closed during a big holiday weekend.”
The Importance of Tall Dunes
Douglass emphasized that extending a shoreline seaward, by increasing beach width, is every bit as effective at reducing storm damages as moving the infrastructure an equal distance landward.
He added that building up the dunes is a good way to protect property.
“Mother Nature takes about 10 to 20 years to build tall dunes,” he explained. “Typically, wind blows sand to the first line of vegetation and gradually the roots reach deeper and deeper to hold the sand in place. As the vegetation grows, it traps more sand.
“We found that we can jump-start Mother Nature by pushing sand into large piles and planting vegetation. So, in many areas dunes were created and sea oats and other types of beach plants were planted to hold and trap sand blown inland by wind and sea surges.”
If the dune holds, he added, you can’t really tell the difference 10 years later between natural and man-made dunes.
“Most rebuilt dunes along the Alabama and northwest Florida gulf coast have held very well,” Douglass said. “Of course, we have not been hit by any major hurricanes, which will be a true test, but none of the storms we have had since Ivan have gotten back to the dune line in a substantial way.”
Browder said that “engineered dunes” became a significant part of beach reconstruction after Ivan. “Everyone saw the benefit of having taller dunes after seeing the damage done by the storm,” he said. “You can look at the before and after pictures and see that some of the worst water damage occurred where the dunes were low or nonexistant.”
At the same time, he explained that beach renourishment is a “soft solution” for storm protection, as opposed to “hard solutions” such as building seawalls.
“In this area, in the absence of severe storms, you don’t need a hard solution because you can deal with most coastal erosion with a soft solution that provides a buffer against storms,” he said. “No one designs a beach renourishment project to withstand the hit of a hurricane like Ivan. It can be done, but would take an enormous amount of money.”
Maintaining Healthy Beaches and Dunes
Douglass stresses that damage to buildings on or near the beach is reduced by three related variables: the width of the beach, the height of the sand dune and the amount of sand in the sand dune at the beginning of the storm.
“It’s important to understand that the dunes, together with wider, deeper beaches provide resiliency against storms and prevent damage to businesses near the beach,” he said. “Beach renourishment is the best money spent to protect our natural resources and property.”
One of the best ways to protect the dunes is to stay off them, according to Douglass.
“Most condos and public areas like the state-owned land on Perdido Key and the Gulf Islands National Seashore, now include fencing and raised walkways over the dunes to reach the beach, which is important to preserving the dunes,” he said. “It’s just good management to keep people from trampling over the dunes. In areas that have been trampled you are more likely to have blowouts from wind and water surges. Eventually, you can cause just as much damage to the dunes by walking across them as they get from a storm.”
West said that rules about dune protection are included in beach regulations for the City of Orange Beach, which state: “Healthy sand dunes provide both valuable protection to upland structures as well as vital habitat to numerous species; for this reason, it is very important to eliminate foot and vehicular traffic in the vegetated dunes. Enjoy the beach, but please Keep Off The Dunes! To cross the dunes and access the beach, please use dune “walkovers” (boardwalks) or designated walking paths through the dune field,
“We need cooperative efforts along with well-thought-out planning and management of our precious natural resources and we need to recognize that sand is one of these important resources,” he said. “That’s why we had to set some regulations to stop people from driving on the dunes, to discourage them from digging deep holes and to prevent them from walking over dunes except at key areas or walkovers.”
He added that people with structures along the beach are “shooting themselves in the foot” if they don’t protect the dunes in front of their property.
“Water tries to find the path of least resistance and those areas where the dunes are worn down are most at risk,” he said. “A storm surge will find the least protected beach areas to move through and then the buildings become more vulnerable. Nourishing the beaches and protecting the dunes is as much about protecting personal property as it is about protecting nature. Fortunately, because of the rebuilding of the beaches and the dunes we are much better off than we were in the years before Ivan.”