Wetland Mitigation Banks
Natural Wanders…
exploring the natural world through writing

Wetland Mitigation
Times of the Islands Magazine
September/October

 Images: Copyright Steven David Miller, protected by international copyright laws.
Do not copy or reproduce in any manner. All rights strictly reserved.
Text: Copyright Linda Lee Rathbun, protected by international copyright laws.
Do not copy or reproduce in any manner without the express permission of the author.
All rights stricly reserved.

Banking on Wetlands
by Linda Lee Rathbun
Photography by Steven David Miller

Florida’s nature is such that she has never fully committed herself to being a landmass. Instead, she has bathed herself in one form of wetland after another; in fact, before development, 20 million acres of the state's 38 million acres were wetlands. This is a truly special place with forested freshwater swamps and sweeping expanses of non-forested freshwater marshes and prairies. Fringing the land are saltwater and brackish wetlands such as mangrove swamps, salt marshes, estuaries, and lagoons.

Those of us lucky enough to live in or visit Southwest Florida, can see that development is occurring at a frightening rate. We are gobbling up available land as fast as we can, and this leads to the loss of wetlands. Fortunately, there are government and state agencies with a mandate to preserve our precious wetlands. However, what happens when development requires that a wetland be destroyed? Well, a whole set of regulations is in place to force developers to compensate, or mitigate, for the loss of one wetland by restoring or creating another. This is known as Wetlands Mitigation and it aims for no net loss of wetlands.

Though a lofty ideal, in practice, mitigation does not always work. The Department of Environmental Protection issued a report in the early 1990s that revealed some alarming problems. 75% of man-made wetlands did not function as they should, and 34% of the mitigation that was required to take place never did. When a wetland was mitigated successfully, there were problems ensuring that it was maintained over the long-term. Another concern was that mitigation was happening in patches: a pond at the back of a shopping center over here, a small lake in a housing development over there; it became known as "postage-stamp mitigation". While these pocket wetlands served a purpose in that they restored or created at least some habitat for wildlife, there had to be a better way. Large tracts of land were also needed, and if there was a way of preserving or restoring one wetland before another was degraded or destroyed, that would be even better. So, in an unlikely marriage of capitalism and conservation, mitigation banks were created.

A mitigation bank is an organization, either public or private, that takes on the responsibility of creating, restoring, and maintaining a wetland. Once the wetland has met vigorous criteria for being viable and fully functioning, the bank is issued credits which can then be sold off. Developers can buy these bank credits as part or all of their mitigation responsibilities. Once the bank has received and sold all the credits available for a particular wetland, the wetland can then be handed over to a government or non-profit organization that will manage it in perpetuity. The bank must also provide enough money to properly manage the wetland by creating a trust fund. This is really an over-simplified explanation of the process, which is, in fact, very complicated. So, let us look at an example, in our very own backyard so to speak, of how it works.

Mariner Properties Development in Fort Myers recognized the potential of mitigation banks. No one can say for sure if their motivation was economic or environmental, but that really doesn't matter if the results work. They had their eye on Little Pine Island, 4,670 acres of public land sitting in Matlacha Pass between Cape Coral and Pine Island. In its pristine days, Little Pine Island was fringed by coastal wetlands, and had a varied interior of wet savannas, buttonwood hammocks, and pine islands. Small variations in land elevation, along with fresh rainwater pooling in the middle of the island, created a patchwork of ecosystems that supported hundreds of species of flora and fauna. The island was privately owned in the 1960s, and our knowledge of the delicate balance of nature was in its infancy. Miles of drainage ditches were dug to drain off the island's surface water in the hope this would control mosquitoes. It did. It also destroyed many natural habitats, and as these died out, melaleuca, Brazilian pepper, and Australian pines took over. Within a matter of decades, the melaleuca trees were so thick no other plant could grow (let alone sprout), and the heart of the island was totally degraded. The Department of Environmental Protection acquired the island in the mid 1970s, but they did not have the funds to restore it.

Mariner Properties Development applied for a permit to turn Little Pine Island into a mitigation bank. This lengthy process required approval by the Department of Environmental Protection, the U.S. Army Corps of Engineers, the regional water management board, U.S. Fish & Wildlife, and any other government agency with a say in wetlands conservation and/or mitigation. The historic ecology of the island had to be evaluated, and strict criteria for determining the success of the restoration had to be met before a single credit would be issued.

Once Mariner acquired the necessary permits from government agencies, they began the process of restoring the island's 1,600-acre interior. This would be done in seven phases. When each phase reached a determined level of success, Mariner would be issued with a portion of the total possible credits which they could then sell to developers in a designated service area: coastal Lee and Charlotte Counties, southern Sarasota County, and Northern Collier County reaching inland to the 100 year floodplain (roughly in line with Highway 41). The entire island would eventually be worth 800 credits. Habitat that was still in tact, like the mangroves, was worth fewer credits than habitat that required intensive restoration.

On Little Pine, restoration involved removing thousands of melaleuca trees. Each tree would be individually cut down and destroyed, and the stump treated locally with a herbicide. An average of 60 tons per acre of exotic plant matter would be removed. Temporary roads would be laid down and then pulled up. About six miles of mosquito ditches would be filled in. Then, one of Mother Nature's miracles of recovery would hopefully take place: native seeds long dormant would sprout and grow. The tidal zone would extend inland once again, and fresh rainwater would pool as it had in the past. Native grasses and rushes, trees, shrubs, and sedges would take hold. Otters, marsh rabbits, turtles, and birds would return.

To date, 700 acres are in active restoration, and three miles of ditches have been filled in as Phase Four reaches completion. Sections where native vegetation did not naturally take hold were planted with native species. Three more phases will restore the 900 remaining acres and fill in another three miles of ditches. So far, the restoration hasbeen a success, and about 200 credits have been issued to Mariner, which they have been able to sell.

So, is Mariner an environmental good guy? Your conclusion will probably depend on how cynical you are about the possibility of a developer being a conservationist. Let us look at a few of the figures. It was estimated that the cost of restoring the interior of Little Pine would run between 10 to 12 million dollars. Mariner’s media consultant, Richard Anderson, says this could rise to 15 million depending on various factors such as weather. Mitigation credits sold to developers run from $35,000 for one credit of herbaceous freshwater wetland, to $49,000 for one credit of forested saltwater wetland. In other words, if a developer destroys a certain amount of mangrove wetland, part of their mitigation responsibility might require them to buy two credits of forested saltwater wetland.

Let us say then that Mariner spends their higher estimate of 15 million and eventually sells 800 credits at an average of $42,000. They stand to make $33,600,000, or $21,600,000 after their costs. 7% of this must be paid to the State of Florida, and 10% must go into a trust fund to maintain Little Pine for perpetuity. That leaves Mariner with a net profit of about 18 million dollars. In addition, they have done the right thing by Little Pine Island, and scored some positive public relation points.

Critics are not so quick to let Mariner and other mitigation banks be the heroes of our wetlands. In the case of Little Pine Island, this was public land to begin with and fully protected from development. Meanwhile, other wetlands that should have been saved were being destroyed. Little Pine Island is roughly equal to about 400 small wetland mitigation projects that could have been scattered across the various counties. Many species of animals depend on these widely scattered "postage-stamp" wetlands. Most salient of all, critics point out, is that "restoring" or "re-creating" a wetland is not the same as conserving an existing natural wetland, and in fact many wetlands cannot be restored at all.

Another criticism is that mitigation banks are an easy out for developers. A developer can buy a certain number of credits, and all their mitigation requirements are met with no further obligation for maintenance etc., on their part. In fact, mitigation banks sell themselves as a cost-saving alternative. For example, if a developer impacts on 12 acres of wetland, they may be required to mitigate 60 acres of wetland at a sample cost of $364,000. That same 12 acres of impacted wetland could be mitigated with 6 bank credits at a sample cost of $154,000, saving the developer $210,000: a one-time cost with no maintenance. Indeed, that does seem like an easy way out.

Those who support mitigation banks defend Mariner’s restoration of Little Pine Island by pointing out it would not have been restored otherwise, public land or not. Also, the failure rate of small wetland projects is so high as to be useless in many cases. Richard Anderson of Mariner feels that critics are not looking at the entire process when they say it is an easy out for developers. Developers must still:
1)Do everything possible to avoid developing a wetland.
2) Minimize damage to the wetland as much as possible.
3) Mitigate by restoring land on-site if possible.

Government agencies, not the developer, determine how mitigation will take place. This might be on-site wetland restoration, off-site restoration, purchasing and donating wetlands to the State to save acreage from future development, and/or buying a determined number or a portion of mitigation bank credits. In most cases, mitigation is a combination of the above. How many credits the developer must buy depends on the quality of the wetland destroyed on-site.

Anderson points out that Little Pine Island can only serve as mitigation for about 1% of the area it services. Most important of all, mitigation banks present one huge advantage over all other forms of mitigation: they provide a proven, fully functional wetland vs. a wetland that may or may not be restored and may or may not be maintained sometime in the future.

Anyone who fully understands the critical role that wetlands play in our environment would hopefully concede that the ideal would be to leave them alone. In the real world, that does not seem possible. Therefore, any and all measures taken to achieve no net loss of wetlands is a good thing. The goal is to have successful mitigation banks that restore large acreages to wetlands, and smaller wetlands scattered across developed areas with wildlife corridors connecting them. The various responsible departments must carry out strict supervision and enforcement of existing rules. Leaving it up to the developers has not worked in the past, and this is a silly expectation given that their interests do not lie in the conservation arena.

All of these arguments aside, it seems that back on Little Pine Island, restoration is working. Close monitoring reveals that: "11 species of mammals, 16 species of reptiles, 7 native species of amphibians, 13 species of native fish, and 46 wetland-dependent bird species are utilizing the restored areas". Many other species continue to use the areas that were not degraded. Migratory birds, and even a pair of nesting bald eagles, are taking advantage of the "new" Little Pine Island.

Little Pine Island Mitigation Bank was the first in Southwest Florida. Mariner is currently going through the permit process to turn 640 acres of land east of I75 into the Corkscrew Regional Mitigation Bank. This will service South Lee County, and be the third mitigation bank in Southwest Florida. Mariner won the bid to be the banker for this land owned by the Corkscrew Regional Ecosystem Watershed. All banks are now required to restore private land, not public land like Little Pine Island.

Panther Island Mitigation Bank was the second to be granted a permit in our region. It acquired 2,775 acres that will be worth 936 credits once success criteria have been achieved. The acres consist of developed agricultural land, degraded wetland, and functioning wetland. The company will be issued with one credit for every 10 acres of the functioning wetland. The pastureland, once it is restored to a functioning wetland, will be worth one credit for each acre of wetland: more costly to achieve, and more valuable in the long-term. The permit took 21 months to obtain, and the bank is finishing up Phase Two of a 7-phase project that will take about five years.

Lew Lauton, the CEO of the Panther Island Mitigation Bank, hopes that eventually Audubon’s Corkscrew Swamp Sanctuary will take over Panther Island. Lauton believes this is logical, given that the land borders Corkscrew Swamp’s 11,000 acres on two sides, and given that Audubon does such a superb job or managing the land they already own. Accompanying the land, will be a 1.5 million-dollar trust fund to pay for all future maintenance.

Audubon has not yet accepted the offer. Ed Carlson, manager of the Sanctuary, says that they have adopted a "wait and see" approach. If and when the wetlands are fully restored, and if Audubon feels they can maintain the wetland with the provided trust fund, then they will be happy to accept Panther Island. Audubon looked at the original plans, and on paper, Carlson says it sounds good. Herbaceous wetlands constructed in tiers to compensate for falling water levels in times of draught would be a boom for wetland dependant birds like the federally endangered wood stork. If all goes well, Audubon’s Corkscrew Swamp Sanctuary will gain 2,775 acres of land.

Most conservationists look at growth in Southwest Florida with a heavy heart--it poses such an overwhelming risk to our wetlands. Let us hope that Mitigation Banks work. Only time will tell if they, and other mitigation restoration projects, restore and maintain the places that attracted so many of us to Southwest Florida in the first place.

THE END