Saving and Restoring the Everglades
From the Enviornmental Review Newsletter Volume Two Number Three, March 1995
Introduction:
Steven Davis is the senior ecologist in the executive office of the South Florida Water Management
Agency. He earned a masters degree in resource management in 1970 from the University of Georgia
and has conducted research on nutrient cycling in the Water Conservation Areas for the agency for
many years. He and John Ogden of the Everglades National Park, are editors of the proceedings of a
1994 book titled: Everglades: The Ecoystem and its Restoration. This book brings together the
contributions of numerous scientists who have spent many years studying some aspect of the
Everglades and presents much of our current knowledge about the history, ecology and hydrology of
the Everglades.
ER: Mr. Davis, how big is the Everglades?
SD: There are different definitions, but what we use in the book is the so-called river of grass south of
Lake, which used to flow south out of lake Okeechobee all the way down to Florida Bay, and
extended from the Atlantic coastal ridge of Florida over into a low ridge to the west that separated the
Everglades from Big Cyprus Swamp. The original Everglades was about 4,800 square miles.
ER: How far is it from the south end of Lake Okeechobee down to the Everglades National Park?
SD: About eighty-four miles to the northern Park boundary and about 130 miles to Florida Bay.
ER: And it's all wetlands?
SD: Well no, not now; it was all wetlands. It is almost exactly fifty percent the size it was at the turn
of the century.
ER: What happened to that fifty percent that is no longer wetlands? What is that land now?
SD: The majority of it has been drained for what is now the Everglades Agricultural Area [referred to
as the EAA. ed.] which is the big sugar cane and vegetable producing area south of the lake. There
has also been encroachment along the east coast into the Everglades. The Everglades used to go all
the way to the coastal ridge which is very close to the Atlantic ocean, and now encroachment has gone
fifteen or twenty miles into what used to be Everglades.
ER: What was done to reclaim the wetlands? Much of the water that used to go into the river of
grass is now diverted out to the ocean isn't it?
SD: That's right. In the natural system - it was very flat terrain to begin with - there would be
spillover from Lake Okeechobee plus nearly sixty inches of local rainfall directly on the Everglades.
And this water very slowly moved south. The estimates are that it would take a year for a drop of
water to go from Lake Okeechobee to Florida Bay.
Beginning in the 1920s, developers started dredging canals. The first were up in the
Kissimmee Basin, above the Everglades but then they extended the canals southward from the lake to
the Atlantic coast. Then, as a result of a couple of major hurricanes in the forties, Congress authorized
the Corps of Engineers to develop a massive flood control project expanding these canals. And the
project built four major canals - huge conveyance capacities and pump stations - from Lake
Okeechobee to the Atlantic coast. They also channelized the river flood plain flowing west out of Lake
Okeechobee and dredged a new channel eastward from the lake to drain Okeechobee water more to
the ocean rather than have it go south over the land.
The project created below what was going to be the Everglades Agricultural Area, the
impoundments called the water conservation areas. To do this a dike was built along the entire east
coast separating the remaining Everglades from what would be urban and agricultural development on
the east coast. The idea was to hold the water back from the east coast so that land could be
eventually developed. And, at the same time, when the water got too high, there were pump stations
and flood gates to release that water through these canals to the coast rather than have it flood the
land.
So we ended up with a series of four major drainage canals that flow through these water
conservation areas and divert a lot of the water that went southward naturally through the Everglades,
now directly out to tidewater.
ER: Is this water being discarded into the ocean?
SD: That's right. And at the same time, doing environmental damage to the saltwater estuaries.
ER: What is being planned for the conservation of the Everglades?
SD: The most comprehensive planning is called the Central and South Florida Restudy being done by
the Corps of Engineers. The Corps has been directed to reevaluate the water management project in
South Florida and to come up with a plan to restore the Everglades ecosystem to the extent possible,
while trying to maintain the present level of flood control and water supply for the human population.
This is a massive undertaking. The Corps has just finished the reconnaissance phase, which has taken
about two years. And assuming they establish a need for the project - which I think they will - then
they go into a planning phase which should last a number of years.
They are looking at replumbing the entire system, even to the extent of tearing out levees and
pump stations and reflooding portions of the EAA as possible proposals; regaining some of the
undeveloped land along the eastern coast and turning that into buffer marshes and reservoirs to hold
the water that needs to be rediverted back to the Everglades, and to capture some of this runoff that is
being lost to tidewater now, and to reestablish natural flows down through the system, all the way
down to Florida Bay. It is a very comprehensive undertaking.
That is the good news; the bad news is whether they are going to be able to do it or not. And
I don't think there is any question about the sincerity of the effort in the Corps in this regard, but the
problem is its time frame and its cost, which are in the range of hundreds of millions of dollars and
decades. And frankly, over that period there are going to be a number of different political
administrations and philosophies in office at the federal and the state level. And to think any political
action is going to stay on course that long is something that needs to be examined. On the other hand,
unless we take a regional view we will probably not do much to correct the situation. We have tried
quick fixes in small areas and have usually made matters worse someplace else in the process.The
only real solutions are regional solutions.
So there are several efforts that are going on in the shorter term that will be happening in the
next two to five years. The district is preparing what we call a lower east coast regional water supply
plan, and it is meant to take the fresh water available in South Florida and allocate it according to the
needs of urban agricultural populations and the natural system. And the expressed priority of this plan
is to fill the natural system water needs first, while maintaining at least status quo for urban and
agricultural areas in for flood protection and water supply.
ER: It sounds like they are trying to make everybody happy.
SD: I think it is politically unreasonable and socially unreasonable to think that we are going to flood
out major agricultural industries and some four million people living down here who are taxpayers and voters. So anything we do down here has to be a balancing act between the urban and agricultural
populations and the environment.
The difference now is that under past attitudes and political regimes, the natural system has
not been given equal consideration. In fact, through most of the century the goal has been to drain the
natural system.
ER: We hear a lot about how important wetlands are for flood control and biological diversity. Is that
true in the Everglades? Is that a good model for wetlands?
SD: I think the Everglades is probably the most important model on earth for several reasons: it is one
of the largest subtropical wetlands and it has been drastically altered in less than a century. And it is a
model in the sense that other countries are looking at the Everglades to see if ecosystem restoration at
this scale can be done. It has never been attempted at this scale. And it is also a model in that we are
preaching wetland conservation to the third world countries - Africa and South America - and if a
country with our economic resources fails to do this, it is a pretty dismal commentary for the rest of
the world. The Everglades is also a model in that it is an essential part of the human life support
system here. It is the major recharge area for the aquifer, from which we get all our drinking water
and irrigation water. The surface water in the Everglades seeps down and recharges the aquifer and
also keeps back salt water intrusion from the ocean into the groundwater. And as far as biodiversity
goes the Everglades is internationally recognized as an international biosphere reserve, as a world
heritage site and one of the most important biodiversity preserves in the world. So I think the
Everglades is a model wetland in all those respects.
ER: Even though its size is reduced by half, it is still a world heritage site?
SD: Sure, it is still huge. Most people do not realize that for all the development that has occurred,
most of the interior of South Florida is undeveloped because it has been so hostile to development.
ER: Why is there more biological diversity in the Everglades than nearby areas on the Gulf Coast?
SD: The biodiversity in the Everglades comes from three sources. The area is unique in that it has
contributions from both the tropical flora and fauna and the temperate flora and fauna, both converging
on South Florida. It is a subtropical environment that can support both of those types. There is a great
amount of diversity in the wetlands system because of this convergence of tropical and temperate
fauna and flora.
The endemic species are mostly relicts from when sea level was much lower in the last 10,000
to 30,000 years and what is now the Everglades was a drier savanna type of habitat. And then with the
rising sea level, all that is left of that savanna is a series of islands going out in the Everglades called
the Miami Rock Ridge. And so the real concentration of endemics are actually terestrial species on
these islands in the Everglades.
ER: The Everglades was a tropical grassland 30,000 years ago?
SD: Yes. There were wooly mammoths and saber toothed tigers. But the Everglades as we see it today
is a very young system. This freshwater wetland is only about 5,000 years old. Before that it was a
drier savanna. And what is now Florida Bay to the south of the Everglades - which is now a salt
water system - was fresh water marsh very similar to the Everglades.
ER: So as the land came up or the sea went down, the wetlands moved north?
SD: Right.
ER: In your chapter of the book you were concerned with both the decrease in size of the Everglades
and its compartmentalization. What can be done to reverse the these trends?
SD: There are opportunities for increasing the size of the system, or at least stopping the loss of the
system: one is saving and restoring the undeveloped lands that are to the east of the water
conservation area levees. And there are still thousands of acres of land in that category that are
threatened now with development. There is action underway to put this land in public ownership. It is
a long process and it usually involves litigation. Of course, land values in South Florida, with growth
as it is, are extremely high and it is a very costly process.
But I think the concept has finally been accepted that even if we are able to recapture some of
this water that we are putting out to tide water now, you have to do two things to that water: you have
to increase the storage capacity of the wetlands so you can hold it; and it is probably not acceptable
water quality to put in what is remaining in the conservation areas, so you have to treat the water in
an open marsh system.
So there is a recognition that land is needed for both of these purposes. The land to the east of
the conservation area is the obvious location for this, so there are efforts underway now by this agency
to buy up that land whenever it is available and even request condemnation on particularly key
portions. There is a controversy going on over a piece of that land now, called the Frog Pond, to the
east of Everglades National Park. It was the headwaters of one of the major drainage systems in the
park called Taylor Slough. That land has been converted to agriculture, and to maintain agriculture
now, water levels have to be maintained at a low level. That being the headwaters of Taylor Slough,
Taylor Slough is now almost dry. And so last week the Florida cabinet authorized the district to
proceed with condemnation procedures on a portion of this land.
The other area that is receiving a lot of attention and debate is the EAA. There are proposals
from conservation groups, and even an alternative listed in the Corps of Engineers Central and South
Florida Restudy Report, that would take major portions of the EAA and turn them back into marsh
flowways to transmit overland flow from Lake Okeechobee down to the conservation areas.
There is already - as a result of the Everglades lawsuit over water quality issues - a plan
underway to convert about 40,000 acres of EAA land into stormwater treatment areas, which are
marsh filtration systems for the agricultural runoff to remove phosphorus before it enters the water
conservation areas. [Phosphorus in the runoff water from agriculture may change the types of plants
and animals that live in the Everglades. ed.]
And with the drainage of the Everglades Agricultural Area - the soil, the peat soil which is
what makes it so productive - is disappearing by oxidation at a fairly rapid rate to the point that
there is speculation as to how long that land will be farmable before it is down to rock.
ER: That shouldn't be so speculative. You've got an established rate of soil loss.
SD: Yes, I tend to agree with you. You hear estimates of maybe thirty years left for parts of the EAA,
and I tend to believe that myself. The speculation comes in when the agricultural industry says no, that
is not the case - that with improved land management and water management they can slow that rate
of subsidence and farm indefinitely into the future. Now the question is whether they are doing that.
At least in the past, farm management in the EAA has been more tradition than advanced water
management to prevent subsidence. Traditionally they pump like crazy every time it rains and irrigate
like crazy when it does not.
I think that there is no doubt that soil is going away in the EAA; it is just the rate. The
question then becomes what happens to that land when it will no longer support sugar cane. Probably
the worst case scenario is that it would go into urban development, an extension of the Miami and Ft.
Lauderdale and West Palm Beach areas. That is not likely because soil loss has lowered ground
elevations about five feet. We have created a big bowl that is going to be increasingly flood prone and
very difficult to drain. You cannot dismiss urban development but it would be difficult to sustain.
ER: The path of least resistance would be to let the EAAs go fallow and build back up, to let the
natural system fill back in.
SD: That has been proposed by a number of organizations. It has been considered in seminars and
workshops by Palm Beach County - most of the EAAs are in Palm Beach County. My feeling is that
there is an opportunity to reclaim some of that as wetland, and also provide better water treatment
before water enters what is left of the Everglades.
We are going to get 40,000 acres for these stormwater treatment areas. That is the heart of the
settlement agreement, as well as the Everglades Forever Act that the Florida legislature passed last
summer. But I think most people feel that 40,000 acres is minimal to do the job. And so my thinking
is that we ought to be picking up land as it goes out of production where there is a willing seller.
ER: How has the Everglades been compartmentalized?
SD: When the conservation areas were constructed, they were divided into three major areas. Area one
is known as Arthur R. Marshall Luxahatchee National Wildlife Refuge. There is a dam at the bottom
of each Water Conservation Area [WCA ed.] to hold water because there is a major water supply
function in that system in groundwater recharge and aquifer recharge.
They then found a couple of WCAs leaked out the bottom. Because of the porous lime rock,
they could not hold water. So they divided the WCAs up further; that is why there is area 2A and 2B
and 3A and 3B; the B's are the leaky part. And they diked that off so they could hold water in 2A
and 3A. And between the conservation areas and the park there was a major dike which is also
Tamiami Trail. And of course, Lake Okeechobee is isolated now from the Everglades because of the
EAA.
The question is, how do you decompartmentalize it without damaging the system further? The
reason for this concern is that in the original everglades system there was a huge storage of water and
a very slow flow of water through the system. All the way from Lake Okeechobee to Florida Bay
during a normal year, most of the land was flooded with a very slow movement of water from the lake
to the bay.
Less than half the storage is left in the system. We have lowered the lake; it used to be about
fifty percent bigger than it is now. We have decreased the size of the Everglades below the lake by
about fifty percent. This was all water storage. We have decreased the storage so once it stops raining,
there is not a residual supply of water to keep this gradual slow movement of water south and keep
the land flooded.
ER: The river of grass?
SD: Yes. The river of grass. When it would rain on Lake Okeechobee or the northern Everglades, it
might take up to a year for that water to get to the south. And in place of that now, we have these
humongous canals and pump stations - the intakes are big enough to put Volkswagens through -
that are meant to get rid of that water in a matter of days rather than over a year.
If we took the divisions out of these compartmentalized areas now, we would end up with
desert in the northern end of the Everglades and lakes in the south end. Because to get the whole area
reflooded would take this slow conveyance which would require this large storage of water to
continually supply that water flow. So I do not think the solution is tearing out all the dividing levees
in the conservation areas. It sounds attractive from an environmental ethics standpoint. And I am not
saying I do not think we should be taking out some levees and pump stations eventually, but it has to
be done carefully or we are going to create a much worse situation. Somehow we have to get that
water storage and that slow conveyance back into the system before we start tearing out the dikes that
are holding back the water and keeping some water in the system now.
You will get people who are not familiar with the system who are well meaning, who see these dikes
and levees and say, "They've gotta go." The real question is whether they should have been put in in
the first place. But now that they are here, it is more than just the dikes and levees that are the
problem. Unless we can reestablish that hydrology, they are almost necessary. We have to manage
these areas as impoundments right now.
ER: Why is it important that the Everglades be expanded? You said it is still huge.
SD: The point is that the Everglades - the park is a relatively a small part of the Everglades, and the
system as a whole is in danger. If you isolated the park as an island, it would not survive as the
Everglades as we know it. It is too small. In fact, the freshwater Everglades in the park is very small.
Most of the park is brackish or saline. The park and the water conservation areas are totally linked and
interdependent - sadly, because of water management practices, all the major wading bird nesting
colonies in the park mainland have now been abandoned and those colonies have moved to the water
conservation areas.
So we view the Everglades as not only the National Park, but the Park, the water conservation
areas, and some of these outlying areas that are not developed. So that argument has been made that if
we have good quality water entering the park in the Luxahatchee Refuge, what's the big deal? Well,
those areas cannot survive as islands on their own. I think we have conclusive evidence that the
ecosystem size of those areas is inadequate to support that biodiversity in those populations of wide-ranging animals.
Copyright 1995 Environmental Review