Seawalls

Please use the quote feature instead of bold responses, otherwise it can become confusing as to who is responding to what. It also helps folks respond to your responses and keep the dialog going. ;-)

Ya know BMBV, you are absolutely correct.

It's been my contention for quite some time (and more so over the last couple years) that all this over development, and the resulting RE money grab, pretty much ruined the area and the beaches anyway.

There was a time not so long ago when I was quite gung-ho about preserving the area's turtle habitat; taking up the cause against over-development and off-shore drilling; and walking the beaches with trash bag in hand picking up litter. The turtles are pretty much history (a couple have been killed during the beach renourishment activities out west); I still pick up litter, but there is SO MUCH MORE now; and most disturbing to me--I couldn't give a rat's rectum if they drilled for oil 20-feet offshore from Seaside.

So go ahead and build as many seawalls, condos and shopping centers as the law allows and why not throw in drilling for oil too.

When it's all said and done, I think once the walls are built and the sand is pumped in and looks as close to "normal" as possible (if Mother Nature is so kind), the owners won't be able to slap "For Sale" signs on those gulffront properties fast enough.

build and shore up what you will, it will all be only a stain on the beach in a few short years time

get rid of all the people

Now, let me ask you something...just curious...why did you ask about the hydrodynamic forces? Can you describe what you see as hydrodynamic forces that would affect the integrity of a retaining wall? I'm not setting you up. I really am curious. There are a couple I can think of but I'll let you go first because I'm a nice guy

Please take the time to reply.

Thank you.

back home now - great trip and lots o fish n/w choc bay and the edges and holes of west west bay probably due to the s/e wind - small grouper (the brown lure ones) around the bridge pilings if you don't get shot



SIA (sorry in advance), but you can always tell when an area is being overdeveloped when the number of realtors outnumbers the politicians

like killer bees into Georgia, the influx of those who build long strings of rental properties and hotels will inevitably occur, either gradually or in spurts (I think we're in one of those habitat decline spurts now) - bubbles grow and pop then grow again - things will settle down once the reasonable property is all built on and the only way to go is up (vertical land), which probably is about where it is heading now

like the date palms and the bouganviellia (?), no property in northwest florida is really native, and walls to stabilize slumping cliffs to hold up houses built on instability itself shall both pass into the night before long

the spring breakers are trampling the dunes, and polluting the water with trash, puke and wee, and they too will be gone soon

then the vacationers will show up for a hectic week of being too busy trying to fit it all in that they can't relax for even one second

all of them drive cars that belch poison gasses, and the poison plane will continue to rain death upon the beach a'la the horror, the horror

about a thousand people will probably end up getting a sunburn during their florida trip that will lead to skin cancer later in their lives

some will even die either getting there or going home or choking on seared ahi at some overcrowded resturant where they waited an hour in line just to get the tuna that killed them

and you guys are worried about some puny retaining walls and slumping dune-built houses, calculatingly not built to withstand hurricane force winds using previous storm statistics to determine the possible chance it would sustain a direct hit! HA! the bluffs were there long before man was, indication a statistical probablility that currents, greed and take would happen

there are still a few undisturbed wild places remaining here and there if you know how to look for them, but their edges are shrinking and the wildlife in them has no place left to go, and the developers are sniffing around them if they can get some sucker to pony up the captial

build and shore up what you will, it will all be only a stain on the beach in a few short years time

get rid of all the people

You left out the red tide that will result from the steel seawalls.:roll:

Second, I'd look into the option of pooling your wall money with other wall builders and fund renourishment of the beach instead. (This topic begs another tangent: why are GF owners so reticent to have public land in front of theirs? That's a disgusting level of greed that thankfully you have not demonstrated.

According to Brad Pickle, to date, there are only three GF property owners who are fighting beach nourishment in SoWal, and they are doing so because they don't want people stopping between their property and the water's edge (the reason you state). ;-)

BMBV,

There are generally two different types of walls in this situation: 1) retaining walls that are designed only to hold back soil/sand and 2) seawalls that are designed to hold back the sand/soil and withstand the forces of battering waves, scour and wave overtopping of the wall.

It is my understanding that, in Florida, for an owner to get a permit to build an armoring type of structure on their coastal property the structure must be designed as a seawall, not a retaining wall. The permit application must (in most situations) be accompanied by a report prepared by a qualified Professional Engineer registered in the State of Florida that shows the wall is designed to survive and be stable under the 30-year return storm conditions, that the top elevation of the seawall is higher than the combination of the highest surge plus the crest of the highest breaking wave, that the wall will not cause flooding or adverse impacts to upland property, the design must consider the 30-year erosion line and the design must consider both static and dynamic forces under these storm conditions.

I would hope that if the engineer was qualified and did their job that report would define for you and the state DEP what the 30-year storm conditions are, the 30-year erosion line is and provide the calculations necessary to show your wall has been properly designed. Of course, all of this was complicated by the fact that permits for temporary walls were given. However, even with that complication, a qualified engineer should have known what the Florida laws were and applied them if these seawalls were to become permanent. In my opinion, given the fact they have to do it to permit a permanent wall, a qualified engineer shouldnt be telling you they cant define what storm conditions theyve designed for just because Acts of God arent insured.

The hydrodynamic forces during a storm will likely be many times greater than the static forces for which a retaining wall is designed. Lets say a retaining wall is designed to hold back 15 ft of water. Take that 15 ft of water and apply it to the gulf side of the wall and give it a speed of 40 to 50 mph and then apply this force every thirty seconds or so over the course of a few hours. If the wall is overtopped, then determine the force of the overtopping water rushing back to the gulf in between waves. While doing this, consider that the sand on at least the gulf side of the wall is eroded away within minutes and the anchors tying the wall back are being loosened by the battering waves. Those are the dynamic forces I see happening and retaining walls likely wont survive these conditions because they are not designed to.

No sad dogs in my house. Sadness and happiness is in the eyes of the beholder, and my dogs are always smiling, unless you try to break into my house, and then it is no-holds-barred.

BMBV:

Three things:

(1) I'm not a realtor. <At least the last time I looked I didn't have a leased BMW in the driveway and a string of pre-construction contracts in my portfolio> My interest in RE is purely for entertainment (and certainly not for investment) purposes.

(2) Despite the fact that I'm saddened over how the "Real Estate Free-for-All Money Grab" left our state and its coastline in ruins and I have an insatiable fascination with the financial train wreck we call the U.S. economy, all-in-all, I'm very content... and I prefer not to view life through a Zoloft-induced haze that makes everything "Okie Dokie" with the world. (I suspect many of the problems the US is experiencing now are because a huge majority of our politicos and government officials are Pfizer Platinum Customers. "Problems? What problems?)

(3) You've got spunk...I like your banter and I understand your situation.

One favor... you know my situation. What is your background and how did you become that familiar with the "retaining wall" vs "seawall" terminology, etc.? Most people don't know the difference. And I have yet to point it out(but I almost did yesterday but fell asleep at the wheel ... I mean keyboard).

I knew when you asked about "hydrodynamic" forces in your previous post that you had a better handle on what's going on more than 99% of the other posters on this message thread.

We all know we have to have a "qualified Professional Engineer". But I have searched the DEP's pdf document regarding your statement about 30-year "return storm conditions". I found 19 instances of "30-year", all of them referring to the erosion line which is the water line itself. I searched for every combination of the words "return storm conditions". Nothing found. If you find a reference, PLEASE do share it with me as I will force our engineer to provide documentation to this effect if required. Is there another document that you are referring to that I'm unaware of that "dictates" armoring design? Because honestly, I don't see that kind of detail in DEP's pdf document. There are just too many types of armoring and materials that they permit.

I'm not sure I quite agree with your visualization of 40 or 50 mile an hour water hitting the wall, but I won't discredit your point, which is a good one. I had the same concerns and voiced this to our original engineer.

Once sand is packed down over the course (under its own weight and assisted with rain) of just a few weeks, it becomes very incompressible.

from pgurney: "If the wall is overtopped, then determine the force of the overtopping water rushing back to the gulf in between waves."

I don't believe this is any significant amount, "hydrodynamically" speaking. Why? Because if the wall is topped by waves, then yes we'll get some sand loss due to scouring on the top... probaby 2,3,4 maybe 5 feet. The wall itself and all the anchors will still be intact. As the water rushes back, it simply goes OVER the wall.

It now becomes a SIMPLE statics exercise (as opposed to dynamics). Simply take the integral of the pressure up the entire wall. Assume the bottom of the wall (part below sealevel) is holding back half the pressure. The rest of the pressure is distributed to the anchoring system depending on their position and their angle.

Not really that difficult for an engineer.

BMBV, it's been an interesting discussion. I appreciate your viewpoints, and your attempts at education where you deem necessary. However, as a lurker and outside observer, these impressions come across:

1. Calling others "Lightweights" who oppose your view, with fewer, shorter, or less impressive words. Foul! Purposefully or not, the inference comes across that you consider yourself a heavyweight. (which begs the question: by virtue of what?) To pull rank for whatever reason diminishes your case in point. Better perhaps to let the facts speak for themselves.

2. Saying in your first post that "we" are the government, (paraphrasing), and then saying in a later post that if we have a problem to take it up with our elected officials (paraphrasing), not those who would follow the rules. If we are the gov't (yes, we are), then let's face it, we all need to act in our best conscious for the generations to come, painful as that path may be at times. The beach is all of ours, not just gulf front owners. Seawalls are by all admissions a temporary solution, and statistically speaking, ultimately result in permanent erosion of the beach berm. And for what? To save a house that--by your admission-- would not survive the storm for which the wall was built in the first place? Your house may not survive, but the wall will. No house for you, no beach for everyone. Take one giant step back: Where's the logic?

That said, I completely appreciate your position of fiduciary responsibility. And I do understand your frustration at being painted in a negative light, when you are doing what you consider to be the best solution for you. The research you have put in is impressive. Put in your shoes I might consider doing the same--I'd have no choice but to consider putting up a sea wall. But first, I'd see if I could feasibly move my house further from the dune--an environmentally conscious solution. Second, I'd look into the option of pooling your wall money with other wall builders and fund renourishment of the beach instead. (This topic begs another tangent: why are GF owners so reticent to have public land in front of theirs? That's a disgusting level of greed that thankfully you have not demonstrated. But back to topic.) In other words, why not use your considerable skills to help organize and enact a long term solution that leaves a positive legacy? Me personally? I'd have to sell my GF house before I could put up a seawall...I could not stomach the thought that I might be contributing to the ultiamte loss of what I consider to be the most beautiful American beach. But I am a lightweight.

3. Ecopal came off as very reasonable, and your repeated attacks on him/her came off as defensive and petty. His/her questions were valid and on the minds of most of us. Why not address them (calmly, and without caps)?

I don't envy the position you're in. Once again, I appreciate --very much-- your posts. Lengthy and defensive as they often are, there's a lot of information contained within, and it's jumpstarted an intelligent debate.

<edited out because I just need to bite my lip instead...>

As a result we have spent approximately $600,000 for just the wall itself (yet another identity hint). I stuck out my neck with my own money and my own reputation (that's called putting your money where your mouth is).

I knew the wall were pricey and the sand even more so. However, I it had not occured to me until just now, but after reading your post, I wonder how you spending, maybe $800,000 idontno: )on protecting your property will effect its market value? Will it make it more likely to sell if listed? Probably. Will a buyer be more willing to fork out the additional $800K for a property which still may not get knocked out by another storm? If a storm hits, is it likely to lose $100K worth of sand? Insurance tough to get, if at all? I really wonder if the property is over-improved, at least for the near term. From the words you write, it doesn't sound like you are a short-term person anyway, so these questions probably will not affect you, but it makes me wonder about other GF properties too. Would they be better off financially just selling (if there was a buyer looking), rather than improving the property?

Cross fire is hell!!

I knew the wall were pricey and the sand even more so. However, I it had not occured to me until just now, but after reading your post, I wonder how you spending, maybe $800,000 idontno: )on protecting your property will effect its market value? Will it make it more likely to sell if listed? Probably. Will a buyer be more willing to fork out the additional $800K for a property which still may not get knocked out by another storm? If a storm hits, is it likely to lose $100K worth of sand? Insurance tough to get, if at all? I really wonder if the property is over-improved, at least for the near term. From the words you write, it doesn't sound like you are a short-term person anyway, so these questions probably will not affect you, but it makes me wonder about other GF properties too. Would they be better off financially just selling (if there was a buyer looking), rather than improving the property?

Interesting questions SJ. I have more.

And BMBV, I am in no way attacking you our your decisions -- just to be clear! -- but I'm wondering in general what is the value in these pre-1985 structures? Why armor at all? It seems like a 600K gamble, albeit in your case a well-researched gamble. Maybe I am missing something, but wouldn't it be logical in many (most?) cases to just use fill sand where the land has eroded, keep the building insured, and if the building and land are washed away by the next storm, rebuild as far back as possible to the newest building codes?

My new insurance policy for our primary residence has a clause where I can pay a higher premium to get 50 percent more money in the event of a total loss, just so I could rebuild to meet the new building codes. Since it is a new state law I assume that option would be available to gulf front owners as well.

When I have peeked at the property appraisers' website it always looks to me like the GF lots are very long and narrow. I'm sure altering or waiving the setback requirements so GF owners could build farther back would not be an issue. So why risk the health of the beach? I'm not saying you, BMBV. I'm saying why is the state allowing the seawalls at all? Or is it likely that many gulf front owners in your situation just would not have enough depth to their property if they had to rebuild?

In North Carolina's outer banks, which are subject to severe erosion, homeowners are not permitted to build seawalls or retaining walls period. They are expected to move their houses back as needed, and in some cases they may lose their property entirely. Obviously it is a different situation (Atlantic vs. Gulf, narrow barrier islands vs. high bluffs) but it is interesting. The culture is different. The risks have always been part of the discussion. As a relatively newly developed area, 30-A hasn't had years and years to hammer out these issues. I appreciate discussions like this because they help advance the dialogue, because it's clear that as a whole the solution has not been reached yet.