It was interesting to learn about the various hard and soft measures for erosion and flood control in coastal areas.  In Manatee County, FL, we can see many of those protection measures in action.  From dunes and beach re-nourishment to seawalls, jetties and beach groins, we have tried them all to protect our little community in the surf.  Let’s take a look at how Manatee County has gone about maintaining the land that is slowly slipping away.

Manatee County began beach re-nourishment projects along the Gulf Coast in 1992 and has continued to bring in truckloads of dredged sand since then about every 10 years.  In 2013, Tropical Storm Debby wiped out approximately 328,000 cubic yards of sand from Anna Maria Island and cost the state and Federal government an additional $37.5 million to restore the dunes and vegetation along with the beach sand.  It has been estimated that by the year 2040 the cost on these re-nourishment projects to increase to as much as $1.7 billion due to the rate of sea level rise, not taking into account severe weather that could cause greater increases.

One relatively large project that began in 2004-2005 was the reclamation of 487 acres of unused and disturbed old farmland turned into a beautiful salt marsh preserve.  Robinson Preserve is now home to mangrove forest, nature trails, emergent islands, and a slew of wildlife including Roseate Spoonbills, Bald Eagles, White Pelicans, and Wood Storks.  A waterway system was reconstructed to allow the natural tidal flows to be restored here as well.

Seawalls can likewise be seen spanning the entire county from residential properties to commercial areas.  Most residents on the barrier islands opt for concrete seawalls where the homes on the interior inter-coastal waterways and inner canal systems have chosen more natural shoreline that has been reinforced with black or white mangrove.  The City of Palmetto most recently chose the removal of an old concrete seawall to make way for a ‘living seawall’ that is the first of it’s kind.  This is a combination of concrete seawall and reef balls that work together to protect the area from flooding, erosion, wave energy and sediment displacement all the while creating a reef habitat for the marine ecosystem below.

Take a look at the difference in the south jetty between Coquina Beach and North Longboat Key.  The jetty was placed here in the late 1950’s for beach retention and to control the waterway in the channel.  The jetty is causing the natural sediment flow northward to be halted now rendering the channel nearly impassible at this point.

A set of three groins was also put into place in the same time period on Conquina Beach north to Cortez Beach.  These groins were added to help stop the erosion of this stretch of beaches.  The groins were originally meant to have a 30 year lifespan and now, 50+ plus years later are in a state of major deterioration.  Plans have been put in place for a new set of three higher tech groins that are adjustable and permeable to allow the county to be able to control the amount of sediment and water flow through them.

Cited:

http://www.islander.org/2014/01/beach-renourishment-on-track-almost/

http://www.floridatrend.com/print/article/15815

http://www.bradenton.com/news/local/article45151770.html

http://ufdc.ufl.edu/

http://www.mymanatee.org/home/government/departments/public-safety/marine-rescue/beaches/beach-safety-information/piers-jetties-and-rocks.html

High-tech groins planned for beach

“A cornerstone of the policy is regional ocean planning – a bottom-up process to address the many competing uses of our ocean. For beachgoers, this provides a unique opportunity to protect special coastal places by steering new potential development, such as wind farms or aquaculture, to less sensitive areas.”

This concept, from the article “Americans Love Our Beaches, But Who Will Protect Them?” really struck me as compelling and thought-provoking. It’s something that seems so understated — there’s a lot that goes into beach and coastal planning that we often take for granted.

This article also made me aware of legislation regarding coastal protection. For example, the BEACH Act of 2000 was put into law to help states pay for water monitoring and public health considerations for beaches across the United States, to the tune of $10 million per year. Since I am entering a graduate program in public health in the fall, learning this was particularly interesting 🙂 I was disappointed to see, however, that this funding is being jeopardized by the same political interests that I’ve talked so much about in other posts.

I was also excited to see in this article that the authors recommendation/discussion of mimicking natural processes when undertaking an effort to protect the coast. I learned so much about strategies to protect coasts this week that I never really thought about but had always seen during trips to the beach. Coastal engineering seems like such a great, rewarding area to work and I am definitely interested in learning more about innovations and emerging strategies to improve coastal well-being both for the coastal systems and for the well-being of people living in coastal areas.

Ultimately, this article made me think about human interaction with coastal processes and how important it is that, while we enjoy the coasts to their fullest potential, we have a responsibility to ensure that our use is as sustainable as possible and to mitigate the negative effects of our actions. This includes the indirect effects, such as the erosive consequences of stronger and more frequent storms related to climate change.

References:

Rotterdam, Netherlands has been planning for global warming and rising sea levels since the early 1990’s.  Before most of the world even acknowledged carbon emissions and warming temperatures would in fact lead to alarming consequences, Rotterdam was preparing for a 1 in 10,000 year storm.  The  Maeslant Storm Surge Barrier, the world’s largest mobile barrier, was built in the 1990s and is made to withstand up to a 3 meters of storm surge.  Unlike New Orleans whose levies were built for a 1 in 100 year storm event, Rotterdam had been looking to the very distant future when preparing for storm surge and sea level rise.  Along with this barrier, Rotterdam has also invested in hard and soft barriers to help with storm surge and rising seas.  Other ideas, such as floating buildings, are also under construction in an effort to find unique ways to solve the damage incurred by rising seas and storm surge.

I believe that Rotterdam is far ahead of the game than many countries, when it comes to creating barriers and infrastructure to withstand rising seas and storm surge.  I do have to wonder how all the hard barriers that have been built have impacted the natural processes of the coast and the ecosystem.  The article highlighted that new structures have mostly been soft barriers, and hopefully this country who is already ahead of its time will come up with innovative solutions that help maintain coastal processes and vulnerable ecosystems, while also protecting life and property from storm surge and rising sea’s.

References:

Bentley, G. C. (2016, June 21). As sea levels rise, Rotterdam shows how to live with water. Retrieved July 03, 2016, from http://www.usatoday.com/story/news/world/2016/06/21/rotterdam-sea-levels/86172926/