Floridas East Coast - How Much Has It Changed?

[bigscoop]

Florida's East Coast - How Much Has It Changed?

I am curious as to just how much the East Coast of Florida has changed since the New World shipping era? Was the beach much wider and the typical waterline further out then, or was it possibly narrower, or was it pretty much just the same as it is today?

 

[Diver_Down]

No one classification will adequately describe such a dynamic environment. In one area where it builds, the sand is being stripped away. A spot north of St. Augustine has remnants of tree stumps that are periodically exposed in the surf zone. Looking at Matanzas Inlet: The original inlet back at the time of Spanish settlers was where the current access ramp is today. The current sand buildup continues. The current inlet has a pair of concrete pillars on the bayside. 5 years ago, these pillars were always in the water. Today, they are part of the beach with an additional 30 yards of sand southward.

 

[GMD52]

Just returned from annual trip to south Fla. and the one thing that was dramatic this year was the large beach reclamation projects up and down the east coast.
a lot of new sand was being dredged from the intercoastal and spread on the ocean side.

 

[Red_desert]

Makes the waterline out further, wouldn't it? Tourism, I suppose would benefit from more beach, harder for treasure hunters to get at the good stuff.

 

[bigscoop]

But I wonder how much actual beach there was during the New World era. Everything would have still been in it's natural state, unaltered by man. It's interesting that some long time residents claim that the ocean is slow encroaching closer and closer to beachfront properties, which would offer the sense that beach is slowly being lost, or at the very least, flattened out.

 

[Diver_Down]

But I wonder how much actual beach there was during the New World era. Everything would have still been in it's natural state, unaltered by man. It's interesting that some long time residents claim that the ocean is slow encroaching closer and closer to beachfront properties, which would offer the sense that beach is slowly being lost, or at the very least, flattened out.

And my first point supports that conclusion. This stretch of shore does not receive renourishment. It is just south of GTM NERR. Tree stumps in the surf are exposed at low tide and after storms.

 

[SorryDangDog]

Back before Florida was developed, the barrier islands that are now Miami Beach, Jupiter Island, Hutchinson Island, all the way up to Sebastian were uninhabited barrier islands that had beaches that ebbed and flowed with the seasons and the storms. Some had mangroves, some didn't. Across what is now the ICW, it was solid mangroves and there were no inlets at Bal Harbour, Haulover (Miami) Lake Worth and a number of other places up and down the SE coast. There weren't any levees draining the Everglades either and contributing even more to the monster tidal flows the were the result....so WAY back when, Florida was a calm sheet of water flowing to the sea and the barrier islands were dynamic and always moving according to the seasons..... who knows where the beaches were and how far in or out they went from what we now know as "mainland". On top of that, after the WW II days and the installation of steel piling breakwaters installed all up and down the coast to try to make waters calmer right at the beaches, those breakwaters disrupted the flow of water and sand and cause even more erosion, just like all the man made inlets, still do to this day....

Look at all of the man made inlets, they all have annual shoaling problems that were created by the digging of the inlets themselves....

So a trivia question of which I don't have the answer.....if the prevailing winds the majority of the year in South Florida are southeasterlies and the Gulfstream flows South to North......why does the sand along the coast flow North to South. I don't know, but it's so!

 

[bigscoop]

I was talking to guy (a native Floridian) today about this topic and he was telling me that there use to be a lot more beach between the dunes and the waterline. He told me he still has pictures that he is going to try to round up showing just how much more beach there use to be. He said if he were to guess from memory that the typical waterline use to be about where the first bar is now.

 

[Diver_Down]

So a trivia question of which I don't have the answer.....if the prevailing winds the majority of the year in South Florida are southeasterlies and the Gulfstream flows South to North......why does the sand along the coast flow North to South. I don't know, but it's so!

Answer: Longshore Current.

 

[Southern_Digger]

I still believe some beaches were further out; and others have since been dredged further out. Today we have Inlets; however, during pre-1900 dredging, we actually had outlets. These were form along the coast when the buildup of fresh backwater washes out to sea. Hence, that is how Spanish obtained fresh water in their casks just by anchoring off the mouth of the Miami River, without ever having to set foot on shore (i.e.: was called the Devil's Punchbowl). Not sure when that name first found its way on early maps but recall seeing it printed in the past. On the other hand, examples that some beaches are now extending further out than in historic past is proven everytime someone goes to excavate for a hotel and discovers the ruins of an old ship: schooner or otherwise. In my area, some have been found while hotels were constructed along Miami Beach; and a few were found farther north.

 

[Jolly Mon]

The real answer is that in some places the beaches have built much further out, while in others, the beaches have eroded. Some of the processes are natural, some are manmade. Check out this study: Characteristics of the Shoreline Change Along the Sandy Beaches of the State of Florida: An Atlas. The data is generally from the mid to late 1800's to the present time and is organized as "historic", "recent", and "total".
http://www.google.com/url?sa=t&rct=...eD5aVLj0UbC3rr1Tg&sig2=_Ws_-Td6KosmdSBWqHGbKA



Sample pages from Indian River County:


If you want a really good idea of deposition vs. erosion on the beaches of Florida over time, this is a great resource. The data is organized county by county and is thus somewhat large scale, but it can definitely point you in the right direction.

As for longshore drift:
GeoBytesGCSE: Coastal Processes: Erosion, Transport and Deposition

 

[bigscoop]

Awesome. Looks it's like time to go to beach school.

 

[Bum Luck]

Awesome. Looks it's like time to go to beach school.

Well, if you want to understand your environment - yes. Knowledge always beats no knowledge.

It helps you to be more effective and successful.

Here's an informative article on beach dynamics for an oft-discussed topic on this board:
Erosion and Coastal Management in Florida - Beachapedia
from that page:
When development and a moving beach come into conflict, a limited number of options present themselves. We can "armor" the beach by constructing sea walls, bulkheads, revetments, or other structures designed to stop erosion. This protects the development in the short term but, without other action, leads to elimination of the beach. Armoring is also very costly, possibly not technically feasible for the long term, and may lead to the perverse result of more development.

Instead of armoring, the development could relocate back from the beach as the beach moves. This has only seldom been used as an approach in Florida, and for large structures is all but impossible. The third option, "nourishment," has been Florida's dominant approach since the 1980s. Nourishment consists of placing sand, usually dredged from an offshore site, on the beach to make the beach higher and wider. For many years nourishment has been presented as a panacea to the conflict between dynamic beaches and development, but it in some cases increases the conflict by promoting more development than otherwise might occur on the beach. In addition, it is increasingly understood that nourishment has severe limits as a general policy for managing beaches. The environmental impacts of beach nourishment on coastal resources may be greater than often realized. Some property owners now fight against beach nourishment as a violation of their property rights. Limited sand supplies and the energy-intensive nature of beach nourishment raise questions about the sustainability of nourishment as a "solution" to dynamic beach movement.

Read the whole page though.