The United States has had a “no net loss” wetlands policy since the concept was embraced by President George Bush in 1989. That same year, the Bay Program went a step further, calling for a short-term wetlands goal of no net loss, and a long-term goal of a “net resource gain.”

These concepts stemmed from concern that four centuries of settlement and development had left huge amounts of wetlands drained, paved, flooded, or converted to other uses. Lost with them were wildlife habitat, the ability to retain flood waters, and a natural water-filtering capability. Roughly half the nation’s wetlands — and slightly more in the Bay watershed — are thought to have been lost since colonial times.

But years after no net loss became the rule of the land — and the Bay region — wetland scientists and government officials are still struggling to decide what the terms “no net loss” and “net resource gain” mean, how they are measured, and how they are to be achieved.

The Bay Program has set no baseline to determine whether it is gaining — or losing — wetland acreage. Even less clear is how to determine whether manmade wetlands constructed to replace natural ones actually replace the functions of those that are destroyed.

“No net loss and net resources gains are very attractive concepts,” said Diane Eckles, of the U.S. Fish and Wildlife Services’ Annapolis Field Office, who has been active in Bay Program wetlands issues. “But I think when you start applying them ecologically, it becomes a real challenge.”

The Bay Program is not alone. The Clinton administration last year released a new wetlands policy, developed by an interagency task force, that promised an executive order “embracing the interim goal of no overall net loss of the nation’s remaining wetlands resource base, and a long-term goal of increasing the quality and quantity of the nation’s wetlands.”

That executive order, which will give federal agencies policy development guidance, has not been issued. In part, that’s because of lingering questions as to how to define — and meet — those goals.

“They have not come up a good way to measure losses and gains of wetlands around the country,” said Dail Brown, of the National Oceanic and Atmospheric Administration’s Chesapeake Bay Office, who served on the task force. “In that sense no net loss is a philosophical goal.”

One problem with meeting the goals is defining exactly what is a wetland.

During much of the 1980s, different federal agencies involved in wetlands regulation — the EPA, the Army Corps of Engineers, the U.S. Fish and Wildlife Service, the Soil Conservation Service — used different identification criteria.

To clarify things, a common manual was adopted in 1989. But the new manual created an uproar because its broader definition classified some farm fields, forests, and other areas that seemed dry most of the year as wetlands. Many people suddenly found they needed a permit to develop their land.

That led the Bush administration to develop a new manual with a narrower definition that required areas to remain wet longer and to have a greater variety of plants. That manual also created an uproar, this time from environmentalists who said it would exempt millions of acres with wetlands functions from regulation.

Finally, federal agencies were instructed to follow an earlier 1987 manual, with some supplemental guidance on how to use it. The National Academy of Sciences was given the job of reviewing the issue and is expected to release its conclusions this fall. After that, the federal agencies will consider whether the NAS findings should be used to again change the manuals.

Even that may not be final. Several bills in Congress could affect wetlands if passed; some by expanding wetland protection, others by narrowing the definition so fewer areas would be covered.

And apart from those regulatory definitions, there is the identification method the USF&WS has used for years to inventory and track wetland trends. Its technical definition, which is similar to that used in the 1989 manual, was developed by a team of scientists from the USF&WS, the U.S. Geological Survey, the National Oceanic and Atmospheric Administration, and the University of Rhode Island in the late 1970s.

As a result, the task of meeting no net loss can be made easier or more difficult by the wetlands definition used as a baseline.

In the Bay Program, for example, some believe that a soon-to-be completed USF&WS wetlands status and trends report [see related story] should serve as a baseline. But others point out that such a baseline would include many wetlands that are not covered by state and federal wetland regulatory programs.

“We need to ascertain some kind of a baseline, but I’m not sure this status and trends report is going to give us that,” said Frank Dawson, chairman of the Bay Program’s Wetlands Workgroup which is grappling with the no-net-loss definition. “When most people first thought of no net loss, they though of it from a regulatory standpoint.”

In developing a goal, Dawson said officials first need to focus on regulatory programs and determine whether they are adequate to stem the losses of those areas identified as “regulated” wetlands. “In looking at what we have a greater ability to affect, first we need to look at it from a regulatory standpoint,” he said.

But others say wetlands provide ecological values regardless of their definition. Mike Hirshfield, senior science adviser for the Chesapeake Bay Foundation, said CBF would likely use the broad definition in the status and trends report to judge the Bay Program’s success in protecting wetlands.

“You don’t want to be looking at a purely regulatory based perspective on wetlands because, as we’ve seen, that changes,” Hirshfield said. “And a lot of the debate about what the baseline should be has been about what definition should you use. The Bay’s health doesn’t suddenly change each time we change definition.”

Even tougher than defining wetlands is figuring out how to create them. Achieving no net loss rests heavily on the assumption that regulatory programs can offset destruction through mitigation — the practice of requiring developers to construct new wetlands to make up for those destroyed.

But replacing wetlands — particularly nontidal wetlands which have complex hydrological and ecological linkages — is difficult. While some may support wetland plants, many scientists say, they often don’t perform all the chemical and habitat functions of a “natural” wetland.

In the past, the mitigation record has been poor. Numerous reports show widespread failure for wetland creation projects in the 1980s. A USF&WS review of 60 projects in Delaware, Maryland, and Virginia during that period found that 70 percent of those projects failed.

“In many cases, no one even attempted to begin the mitigation,” said Bob Zepp, of the USF&WS’ Annapolis Field Office. “Some people thought it was a joke and didn’t bother with it. Some attempted it halfheartedly and scratched the ground a little bit, cut off a little brush and hoped it would become a wetland, and it didn’t. Sometimes they were supposed to create 2.6 acres, and they created 0.6. We were getting shortchanged on a lot of them.”

But some, like Leonard Shabman, a resource and environment economist at Virginia Tech, attribute the poor mitigation record to “institutional failure.” Agencies that required mitigation in the 1980s often failed to require adequate follow-up steps to ensure success. “We know how to do it,” he said. “We just haven’t had the people out there making sure it was done right.”

Understanding what makes mitigation — and mitigation programs — a success has lagged because of controversies between environmental groups and developers during the past decade, said Dennis King, of the University of Maryland’s Chesapeake Biological Laboratory. Developers were interested in doing cheap mitigation so they could go ahead with projects while environmentalists opposed mitigation because they feared it would be used to facilitate wetland destruction. As a result, little work has been done to guide officials developing mitigation programs. “We’re playing catch up and studying a lot of things at once,” he said, “meanwhile the mitigation train has left the station.”

King has built a database of more than 1,000 mitigation efforts across the country to help determine what cost-related factors lead to successful wetland creation. On the average, he has found that successful mitigation costs about two-thirds more than failures, and most historical projects have been funded at levels that almost assure failure. And economic incentives — such as requiring bonds — also help promote success.

Increasingly, states and the federal government are adopting tougher requirements. The Corps of Engineers and all of the Bay states require follow-up monitoring and maintenance of sites — usually for five years — to improve chances of success.

Maryland has gone even further. It requires someone who destroy a wetland to not only replace it — which costs on average $55,000 an acre on the Western Shore — but to also post a $20,000 per acre bond. DNR staff inspect the sites each year as well.

“You need to monitor, you need to bond, and you need to actually go out and look at these sites on a somewhat regular basis,” said Kevin Smith, who oversees wetland mitigation efforts for the DNR.

Still, he said, Maryland’s program is too new — it began in 1991 — to determine whether the mitigation projects have succeeded. “If you create a wetland area, plant it with all these wetland species, and you go out there the next day, it looks beautiful,” he said. “Is it a success? Well, not really. Let’s give it some time to adjust itself, see what kind of vegetation is going to become acclimated, and then we can start making some determinations as to whether we have successes or failures.”

Even if mitigation projects succeed in replacing acreage lost to development, they still would not meet the federal and Bay Program goals. Those goals, after all, call for a no net loss of “acreage and function.”

While many wetlands scientists and regulators agree that wetlands can be created under the right conditions, few argue that the new wetlands replace the functions — such as wildlife habitat, water filtering ability, nutrient removal capacity, and other benefits — of natural ones, which took years to develop.

Many functions are difficult to replace. Most nontidal wetlands in the Bay watershed are forested, which are almost impossible to replace — at least quickly.

“It takes 250 years to produce a 250-year-old woodland with dead trees and rotten logs on the ground and all the rest of it,” said Curtis Bohlen, a wetland scientist who works with King, and who previously worked for the Chesapeake Bay Foundation. “Many of those things that take a long time to develop are structurally important for salamander habitat for wood duck nesting sites — you can tick off a list of wetland characteristics unique to older sites — and you can only rush those things so much.“

To make up for that, mitigation programs often require people to construct more wetlands than they destroy. “By providing more of an area, it’s providing more function — but obviously you’re not going to gain those forested functions until that particular wetland reaches an age where it’s going to perform the same as the impacted wetland,” said DNR’s Smith. Trying to gauge no net loss in terms of wetlands function, Smith said, “would be an incredible task” because so much remains unknown about wetlands.

The Bay Program is considering a research project that would help plug that knowledge gap. Eckles, of the USF&WS, has proposed research in a series of “reference wetlands” — including wetlands of different types and with different degrees of degradation — located in each geologic region of the Bay watershed. The studies would examine wetlands soils, habitat, water chemistry, and linkages to the surrounding land. Findings, which would become available in as little as a year, could help managers better assess the functions being lost when wetlands are destroyed.

“That kind of information is desperately needed in order to really look at the no-net-loss aspect,” Eckles said. “It’s basically trying to understand the processes and functions that are occurring in that wetland and how they fit in a landscape. We are not doing that.”

Too often, she said, small chunks of wetlands are removed with little regard about their relationship to nearby land. In reality, she said, a small piece of wetland — even a degraded one — may provide important functions relative to the nearby landscape. For example, a degraded wetland filled with phragmites — an exotic species — may be important if it is located in a polluted area because phragmites binds soils together, keeping any contaminated soil from washing away, and absorbs pollutants better than some other wetlands species.

“This is complicated, but that is ecology,” she said. “We have reduced what we do in compensatory mitigation to basically something that is administratively easy because it’s part of a bureaucratic process. And that’s not where we should be going.”

And wetland values may not be limited strictly to ecological functions. In some cases, according to King, it may be important to retain wetlands — even poor quality ones — in cities because of their potential educational value.

"If your goal is to have each urban kid under 12 years old hear as many songbirds as gunshots, that’s a value,” King said. “Even if you have a degraded wetland in Baltimore somewhere, it might be important for an urban kid to see a grasshopper now and then.”

Of more than a dozen scientists, economists, and regulatory officials interviewed, none thought the nation or the region would achieve a net gain — and perhaps not even a no-net-loss — objective through current site-by-site regulatory programs.

At best, they said, existing programs may hold the line on acreage and functions lost to development. But some wetlands are lost through natural processes such as beaver dams. In either case, gaining wetlands and functions will require some innovative restoration programs, many agreed.

“It’s difficult to get away from the permit-by-permit philosophy,” said Ken Reisinger, chief of the Pennsylvania Department of Environmental Resources’ Wetlands Division. But in some cases, he said alternatives should be explored. For example, he said that in 1992, the DER issued 117 permits that affected less than a quarter acre of land — 11.5 acres in all. Not only will many of their replacements lack the functions of the destroyed wetlands, many will fail altogether. He said a DER review found that only about 50 percent of the projects of half-an-acre or less become “healthy, viable wetlands.”

In such cases, Reisinger suggested that regulatory programs in the future may include innovative mechanisms. He suggested, for example, that people destroying small wetlands could pay into a fund which would be used to underwrite local efforts of conservation groups or others who want to build wetlands — and often build significantly more wetlands than were being destroyed. “We need to incorporate these kinds of things in our programs,” he said.

Many suggested that more thought needs to be placed on what roles wetlands are playing within a particular watershed. If that were done, they say, it would be easier to determine which wetlands should be most protected, where mitigation is most important, and where replacement wetlands should be built.

Carin Bisland, living resources coordinator in the EPA Chesapeake Bay Program Office, suggested that restoration efforts within a given watershed might be directed at target species — such as spawning habitat for anadromous fish — rather than being strictly tied to an accounting mechanism aimed at offsetting acreage losses and specific functions. “I’d like to have a vision of where we’re going based on the resources,” she said.

A few non-regulatory approaches to wetland creation are under way. The Bay Program, for example, is involved in several wetlands construction projects, including one that uses dredge spoils dug out of shipping channels.

On a smaller scale, the USF&WS’ Partners for Wildlife Program provides technical and financial assistance to private landowners to convert their property to wetlands that will provide wildlife habitat. Also, the federal government has proposed expanding the Department of Agriculture’s wetland reserve program which reimburses farmers who agree to let portions of their cropland return to wetlands.

There are barriers, though. While the USF&WS has had success with its Partners for Wildlife Program in Pennsylvania and Virginia, it has had less luck in Maryland. Some say that is because restoration programs often lack enough incentives for people to sign up.

“In the Bay region, there are grossly inflated expectations of land prices,” Shabman said. “Everyone thinks lightning will strike and their land will be the next shopping center or highway interchange, and they will get rich. If you go to a landowner and say, ‘how would you like to put your land into a perpetual wetland easement and we’ll give you 50 bucks a year,’ and the landowner thinks he’s going to be the next Wal-Mart location, he’s not interested.”

“In order for these kind of acquisition programs to work well in the Chesapeake Bay basin, we’re going to have to do something about property price expectations. That means we’re going to have to do something about land settlement — which gets us back to the population-growth issue.”

Tidal and Nontidal Wetlands

Two major groups of wetlands are found in the the Bay watershed, coastal (estuarine), and inland (palustrine) wetlands. Coastal wetlands are influenced by tides and contain waters that range from nearly fresh to fully salt water. Inland wetlands include freshwater, nontidal areas.

Salt marshes are coastal plant communities dominated by herbaceous (nonwoody) vegetation subject to tidal flooding. Salt marshes consist of low marsh zones, flooded by every high tide, and high marsh zones, flooded only by extremely high tides or storms. Salt-tolerant plants such as smooth cordgrass are found in the low marshes, whereas high marshes may contain saltmeadow hay, black needlerush, switchgrass, saltgrass, and marsh elder.

Freshwater tidal marshes also have low and high marsh zones, similar to salt marshes. The degree of flooding determines where certain plant species occur. Commonly found along the water’s edge are wild rice, arrow arum, pickerelweed, and yellow pond lily. In the higher tidal fresh marsh are often cattails, big cordgrass, and marsh hibiscus.

Nontidal wetlands, which are beyond the upstream limit of tidal influence, are more abundant than tidal wetlands. Nontidal marshes frequently contain bulrush, broad leaved cattail, spikerushes, jewel weed, soft rush, woolgrass, and sedges. River floodplains and streamside forests, called riparian areas, often contain large expanses of forested wetlands.

Swamps are a type of forested wetland which may have permanent surface water, or may be seasonally inundated with water. Common trees in a wooded swamp include red maple, black gum, river birch, black willow, Atlantic white cedar, and bald cypress. Shrub swamps may contain willow, alders, and buttonbushes.

— Source: U.S. Fish and Wildlife Service

Wetlands and their Functions

A wetland is generally defined as an area where the saturation of the soil is the dominant factor determining plant, animal, and soil composition. Typically, these lands are transitional areas between terrestrial and aquatic systems. Because of this relationship with both land and water, wetlands provide critical food and habitat for a wide variety of fish and wildlife.

In contrast to their past, when wetlands were considered to be unimportant, wetlands are now recognized for a variety of important functions:

  • They provide vital resting, breeding, and feeding habitat for birds, including migratory waterfowl such as ducks and geese. More than half of all threatened and endangered species depend directly or indirectly on wetlands during their life cycle.
  • They provide economic benefits, including spawning grounds for commercially valuable fish and shellfish.
  • They help maintain water quality by filtering out pollutants to purify water before it enters streams, lakes, or oceans.
  • They control floods by slowing down and absorbing excess water during storms and then slowly releasing the stored water to reduce peak flows.
  • They protect coastal and upland areas from erosion by absorbing and dissipating the impact of waves.
  • They provide aesthetic and recreational opportunities, including fishing, hunting, and birdwatching.

— Sources: National Oceanic and Atmospheric Administration, U.S. General Accounting Office.