Sea level rise affects the Keys now.
Posted by JAC on 1/12/2010, 6:48 am

Conchs & climate change: Sea level rise affects the Keys now

By George Neugent
January 10, 2010







Saltwater incursion is seen at on the Sombrero Country Club golf course in Marathon, Thursday, Dec. 10, 2009. (Joe Cavaretta, Sun Sentinel / December 9, 2009)


Let me start by saying that I'm not trying to take a Chicken Little approach by saying the sky is falling. However, as an elected official and a longtime resident of the Florida Keys, I think we have to take the issue of climate change seriously and do our utmost to address it.

Sea level rise is a very real concern in many parts of the Keys. It impacts us particularly during high tide events when water tables are elevated and surface water has nowhere to go. While we're seeing this particular impact of climate change throughout Monroe County, this problem is by no means restricted to the Keys. Other low lying areas of South Florida are beginning to see such problems, and it's an issue that we're going to have to deal with in the future.

Yes, there is a lot of discussion as to the validity of climate change and sea level rise, but I am convinced that the Earth is warming, and that greenhouse gas emissions are exacerbating the situation. Most folks, if it's not something that's impacting them directly, take an approach that I'm not going to worry about it. Certainly we have skeptics here. It's a subject that's put on the backburner by many, and there are those who take a position that it's not happening at all.

As elected officials, we don't have that luxury. Let us take you on a tour and show you where rising sea levels, even at minimal degrees, are taking a toll in the form of ever higher tides and frequent storm surges. Read on, and I'll show you why we're at risk as time passes and the seas continue to rise.

Key Largo - We'll start with the Upper Keys, an area many think is relatively safe from flooding. Not so in a neighborhood that is not all that far from John Pennekamp Coral Reef State Park and the place where The African Queen is docked. The county has gotten calls from residents living along Shaw Drive and Adams Drive on the bayside of the key. The low-lying streets are ripe for flooding, particularly during storm events and periods of high tides.

We've got roads on the key that need to be elevated, some by as many as 18 inches. Those roads were built out in the lower points of the key. When they were built back some 30 to 40 years ago, they didn't muck out the material so they're sinking, too, as they get more use. So we're not only losing them to the tide but because of the use. You can stand there and when a dump truck goes by you can feel it shake like Jell-o. We elevated Card Sound Road almost 11 years ago because it was flooding. We spent a lot of money doing that.I don't remember the exact amount but $7 million sticks in my mind. They didn't muck the road out when they were building it. The road sank, and the tide's coming over it, and that was one of our evacuation routes.

Marathon - The Sombrero Golf and Country Club is one of six private golf courses in the Keys. This one is located on the oceanside, closer to the southwest end of the key and the famed Seven Mile Bridge. It is near some of the key's best dive sites, like Sombrero Reef and Washerwoman Shoal. It hasn't rained here in a while but the pools of water you'll see are just laying on top of the salt water beneath the surface. This water literally has no place to go.

During Hurricane George in 1998, this golf course was completely inundated with about three feet of water, and you could see the pooling effect. So now the focus is trying to keep the fairways green and, of course, golf courses love water. They just don't love salt water. The area over the driving range used to have a lot more grass. For the time being, they placed their priorities on other pars of the course.

The 7th hole has been elevated by about a foot to protect the fairway from the tidal influence and salt water intrusion. Over the rise by the 2nd hole, they raised the fairway by a foot and began planting Paspalum, a salt water resistant grass. It holds up better but it's more expensive than your traditional Bermuda grass. They're now building what is essentially a dike, a levee around the course to try to keep the water out, but I don't understand the efficacy of it. It will help keep waters off the course when they're influenced by the wind, but again as that water comes up, as it will when we have the astronaumically high tides.

We're 125 miles from 5 million people who like to come down here for the weekend to dive, fish, go loberstering or play golf. We've become a year around destination with tourism spikes when our snowbirds come down. This is a very valuable piece of land, but the high cost to maintain it, to keep it as a playable golf course is challenging. Sea level rise is so insidious. If you don't experience it yourself, it's just in the back of your mind. But when you can touch and feel it, you have to say something is going on here.

Big Pine Key - This particular island is better known for its federal designation as The Key Deer National Wildlife Refuge, which is home to roughly 300 unique Florida Key Deer. At the beginning of the key is St. Peters Church and the home of one of my favorite Catholic priests, Father Tony. He is quite the character, but what you need to see is how damp the area is behind the church. The water behind the property is part of Coupon Bight. It started out as an old pit where they did excavation and took that out for fill. The bight has natural flow out to the ocean at high tide. This pit used to be landlocked, but not anymore. During both hurricanes George and Wilma, all this was under water. All that water was pushed up here over a buffer of land, and it flooded the church and the rectory. The U.S. Fish and Wildlife purchased this buffer of land behind the church as a natural area to expand the land area of the Key Deer, but during a major storm event, all this would be underwater.

Drive towards the Watson's Hammock nature preserve and the Blue Hole, the largest body of fresh water in the Keys and you'll notice some of the dead pine trees - bleached and bare limbs that were once healthy until the earth that supported them became inundated with salt water. That's what happened in an area located just south of the Pine Heights subdivision on the north end of the Big Pine Slough, where you can now see plenty of dead vegetation and the more hardy buttonwood. Pines can't live in salt water. It's impossible to say exactly what killed the old dead pine stumps, but we know that the newly dead trees were killed by the saltwater surge of Hurricane Wilma. In a nutshell, due to sea level rise, both tides and storm surges reach higher than they used to, and that rise is predicted to continue and the rate is expected to accelerate.

Stock Island - This is the last island one crosses before reaching Key West. It's the home of the Tennessee Williams Fine Arts Center, Key West Kennel Club. Many of the people who work in and around Key West live here. It's also also an area prone to tidal flooding, particularly along Shrimp Road on the oceanside of the island. When it rains during high tides, sections of the street flood, with waters rising as high as three to four feet.

Shrimp Road isn't the only low-lying area on the island that's prone to flooding. We got six inches of rain last month, and there was this one business out on the island that was flooded. The county got the call: "The drains are flooded, the drains are flooded." The drains weren't flooded. It was high tide. They got a pump to pump out water into another drain to help their situation, but it wouldn't go anywhere because of the tides. It was like dipping the ocean dry with a spoon.

Key West - The highest natural elevation in the city is Solaris Hill, which I believe, is about 14 feet above sea level. A lot of the city, though, is at a much lower elevation. Some parts of the new section, for example, are just one or two feet above sea level. Some parts of the city have injection wells to help reduce flooding, but at high tide the water comes through them and floods the streets.

On Flagler Avenue, on the end of the island closest to Higgs Beach and the Southernmost Point in the Continental U.S., there are sections of the road where water comes up through the storm drain system and covers the parking lanes during high tide, and sometimes it gets out into the driving lanes. It used to be a rare occurrence. Now water comes out of the drains at least once a month. On Moorside Drive, which is not far from where we are now in out in the city's New Section, the city had a valve in which they used to close the drainage system so that it wouldn't flood out there. But I understand at some point someone took the valve out so now the street floods there again. First Street, which is not too far from here, has low level floods just because of the low elevations we have.

We have very porous limerock down here. It's basically old reef material formed millions of years ago, and unlike say the clay in Louisiana, which is impenertrable, we get a hydrolic pumping affect with the tides and we're seeing more and more instances where the water has no place to go. We're getting more complaints. We have a list of about 40 county roads throughout the Keys that need to be elevated. Right now we don't have the money to do it.

The Keys has always had tides, and it's always had storms. But this is the first time in history that people are literally contributing to the sea level rise - albeit indirectly by deforestation and greenhouse gas emissions. For those of us here in the Keys, as in low-lying coastal areas everywhere, we need to figure out how to minimize the negative consequences of sea level rise and to adapt to the consequences that we can't control.

George Neugent is the Monroe County Mayor. Chris Bergh of the Nature Conservatory on Big Pine Key and Dent Pierce, the county's Public Works director and a Key West resident, also contributed to this story. Copyright © 2010, South Florida Sun-Sentinel


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Sea level rise affects the Keys now. - JAC, 1/12/2010, 6:48 am
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