A. WETLANDS PROTECTION AND RESTORATION

SCOPE OF THE ISSUE

Coastal wetlands form transitional areas between permanently flooded fresh and marine aquatic environments and well-drained uplands. The boundaries of wetlands in coastal environments are often subtle, phasing gradually from saltwater to freshwater. As transition areas, these habitats have features of both aquatic and upland ecosystems and form some of the earth's richest and most diverse and productive habitats, often rivaling our most productive agricultural operations. Wetland habitats fringe the ocean coastlines, the Great Lakes, and the various riverine areas of the United States, with major concentrations found within the estuaries of the Gulf of Mexico and the South Atlantic coast.

Wetlands provide numerous important ecological functions. They provide protected areas that act as nurseries and temporary shelter to many aquatic species, including numerous endangered species. Two-thirds of all commercially important species, such as flounder, menhaden, shrimp, oysters and clams, spend either a part or all of their lives in estuarine waters and adjacent wetlands. In addition, nearly all waterfowl, wading birds and shorebirds migrating along the North American flyways find abundant food, rest stops and/or suitable nesting throughout the fresh and salt marsh complexes and mudflats of coastal estuaries.

Wetlands losses have resulted from a number of natural events and human activities. Some of the human activities include dredging and filling; resource extraction, such as oil, gas and sand; contaminated stormwater runoff; introduction of non-native species; and, the construction of features which reduce tidal flow and/or influence the amount and duration of freshwater inflows into estuarine systems. Natural events include coastal storms such as hurricanes and floods; salt water intrusion due to sea level change and land subsidence; the natural succession of wetlands into coastal upland habitats; and the introduction of exotic species.

Coastal America's wetland projects are examining and restoring some of the damage caused by man's intrusion upon these natural systems. Projects are being implemented to address the impacts from roads and railbeds which have constricted tidal flow into coastal salt marshes. Other projects are restoring historic hydrologic patterns disrupted by other types of construction, enabling degraded wetlands to return to productive conditions. Still other projects are examining the restoration of degraded wetland communities impacted by diking for agricultural purposes. Finally, a number of projects are restoring degraded wetlands impacted by diffuse and unwise land use practices.

SELECTED PROJECT SUMMARIES

For the purposes of this discussion and for ease of analysis our Wetland Protection and Restoration Projects have been divided into four categories: Restoration of Transportation Related Impacts; Restoration of Hydraulic Patterns; Restoration With Dredged Sediments; and the Restoration of Degraded Aquatic Sites.

Critical to the nation's economy is its ability to transport goods and people from one location to another along safe and efficient waterways, roads and rail systems. Manufacturers, commuters, tourists and federal and state governments all depend on these systems. These transportation systems are designed to connect areas of commercial, industrial and residential development. In the northeastern U.S. the development of transportation infrastructure historically occurred within the coastal wetland environment, an area once considered undesirable at the time of the infrastructure's construction. Many of these transportation projects are now in need of major rehabilitation in order to meet the challenges of the twenty-first century. Their rehabilitation provides a unique opportunity to undertake wetland restoration projects and thus, correct some of the unintended environmental mistakes of the past.

There are two major coastal estuary projects that are located in Coastal America's Northeast region, the Connecticut Coastal Embayments project and the Cape Cod Coastal Embayments project. These two projects have the potential to restore nearly 1500 acres of coastal wetlands by re-establishing tidal flows to many of the isolated wetland areas that were cut off from normal tidal influence.

Connecticut Coastal Embayments, CT

In 1991 the Connecticut Department of Environmental Protection (DEP) requested a study be conducted by Coastal America to identify salt marshes that have been degraded as a result of tidal flow restrictions caused by the placement of transportation facilities, especially roads and railroads. An initial $100,000 study was conducted by the Army Corps of Engineers (COE) under Section 22 of the Water resources Development Act of 1974 (WRDA, 1974) which authorizes the COE to cooperate with any state, at their request, in the preparation of cost shared, comprehensive plans for water resources development, utilization, and conservation, i.e., the Planning Assistance to States Program. Matching funds were provided through Connecticut DEP's Long Island Sound Cleanup Account for the restoration of degraded coves, embayments and tidal wetlands. The study was to determine the locations of salt marshes degraded by roadway and railbed construction, which sites would most benefit by some form of tidal restoration, and to evaluate the relationship of transportation crossings to wetland degradation. Particular attention was given to sites where the dominant species was the common reed, Phragmites australis, a highly invasive plant that dominates disturbed and tidally restricted areas and is considered ecologically less productive.

A Technical Advisory Committee (TAC) was formed to select study sites and provide technical review. The TAC was comprised of the Coastal America partners including the COE, the U.S. Department of Transportation (DOT), the Environmental Protection Agency (EPA), the U.S. Fish and Wildlife Service (FWS), the National Marine Fisheries Service (NMFS), Connecticut DEP and DOT, plus other wetland managers and scientists. All degraded or degrading salt marshes between New Haven and the Connecticut - Rhode Island border were considered. The study specifically evaluated the effect of the transportation facilities on tidal flows, documented existing biological conditions and determined, through analysis of historic photographs and other data, the historic wetland conditions, i.e., were these sites formerly salt marsh, brackish meadow marsh, and/or brackish reed marsh. Assessments also considered the potential impacts from increased tidal flow on adjacent land uses such as housing and commercial activities. The importance of the area as habitat for local wildlife was also considered, especially if the species were listed as endangered or threatened, or if there was potential for recruitment of new, desirable species under the anticipated new salinity regime.

From this initial assessment, ten wetland sites were selected for further study and six were found to be experiencing degradation as a result of transportation related tidal flow restrictions. Using the results of the Coastal America study, Connecticut DEP applied for and received U.S. DOT Intermodal Surface Transportation Efficiency Act (ISTEA) funding for the restoration of Sybil Creek and Mill Meadows salt marshes in 1994. The funding was channeled through the Connecticut DOT that was instrumental in convincing the Federal Highway Administration that wetland restoration was an eligible enhancement activity, i.e., it provided for scenic beautification and stormwater mitigation, under ISTEA. This project represents the first commitment of ISTEA funding for salt marsh restoration in the United States. The Northeast RIT provided technical assistance at these degraded salt marsh sites. Additional funding was also provided from EPA's National Estuary Program. It is anticipated that additional restoration projects will be implemented by the State of Connecticut's Long Island Sound Program.

Subsequently, based upon these initial assessments, the Connecticut Congressional delegation drafted legislation to provide for a comprehensive examination of degraded coastal wetlands. Section 346 of WRDA 1992 authorized the COE to undertake a comprehensive examination of potential wetland restoration projects; however, appropriations have not been requested to implement this provision. Additional federal implementation vehicles are being pursued for three additional wetland sites by the Northeast RIT.

Cape Cod Coastal Embayments, MA

In 1990 the Massachusetts Department of Environmental Protection (DEP) initiated a $100,000 study to reconstruct some of the road and railbeds within their coastal zone and to restore any degraded wetlands associated with this infrastructure. This initial investigation was undertaken to examine the potential restoration of 500 to 1000 acres of salt marsh cut off from tidal influence by transportation infrastructure. The Massachusetts DEP requested the COE assist in the investigation. It is anticipated that by designing culverts to provide tidal flows that more closely approximate natural conditions and by constructing larger channels in and around transportation facilities the productivity of these marshes will be restored. Funding for these activities was provided by the ISTEA via the Massachusetts Executive Office of Transportation and Construction. Additional funding was provided by the COE Planning Assistance to States Program. Further, these activities received technical support from EPA's National Estuary Program and the Gulf of Maine Program.

Technical Lessons Learned:

1. High marshes dominated by the common reed, Phragmites australis, a highly invasive plant with little to no ecological value, are particularly well-suited for restoration by increased saline flushing. The higher salinities tend to help more desirable and productive salt marsh vegetation out compete the Phragmites australis. Further, in addition to being of low ecological value, these woody stands can rapidly accumulate large volumes of combustible plant material creating a fire hazard. Thus, the Northeast RIT has determined that the elimination of these monotypic stands of Phragmites australis is the most significant restoration effort they can undertake.
2. Phragmites australis is generally intolerant of soil salinities greater than 18 ppt and will disappear from a degraded site over a period of from 5-10 years depending upon the size of the marsh. As the Phragmites australis disappears, native salt marsh plants will often recolonize spontaneously, thereby precluding the need for expensive and difficult planting and transplanting projects.
3. Increased salinity conditions may cause some unfavorable ecological consequences, such as subjecting shellfish beds to greater predation and/or the proliferation of protozoan diseases. Thus, care must be exercised in determining the level of salinity desired in any given location.
4. Draining salt marsh peat can lead to the formation of sulfate soils that are highly acidic. Organic leachate from these soils has been shown to cause hypoxia and anoxia in receiving waters and often leads to fish kills. Acid leachate has also been shown to shorten the longevity of metal and concrete structures. Finally, draining of salt marshes can lead to significant subsidence caused by the increased decomposition of the organic material.
5. Restoring tidal flow can be detrimental as well as beneficial, because it can introduce undesirable species into an area that may out compete existing, desirable species based upon the salinity tolerance of the species involved. Restored tidal flows can also flood residential septic systems and potentially impact groundwater supplies.
6. Structures such as undersized culverts and tide gates, which reduce or eliminate tidal flow, cause a progressive but gradual replacement of the diverse salt marsh plant communities with the tall woody and monotypic stands of the common reed. In general, bridges do not cause an overall flow restriction, with any initial constrictions being compensated for by increased water depths caused by scour below the bridge.

Procedural Lessons Learned:

1. The rehabilitation of transportation and water resources infrastructure provides opportunities for ecological restoration of wetland systems negatively impacted by these structures. These restoration efforts can re-establish biological diversity, abate nonpoint source pollution, and enhance stormwater treatment through the incorporation of newer, more environmentally compatible designs. This can be accomplished by utilizing the environmental provisions of the ISTEA and those of the various WRDA's as well as applicable environmental statutes and programs.
2. When designing projects to restore coastal wetland systems, the desired proportion of fresh, intermediate, brackish and saline marshes should be determined in order to assist project engineers in the design and operation of water control structures that will influence tidal flows and ultimately, the nature of the restored marsh system. For example, in marshes that have experienced significant subsidence, replacement structures should be designed to restore tidal flows only to the extent necessary to replicate the hydroperiod of the natural marshes being established.
3. When designing projects to restore wetland systems, existing development and the desires of the local community must be considered so that their needs are also factored into the overall restoration plan. For example, restoring natural tidal flows may increase the risk of flooding to existing residential and commercial establishments, thus, requiring appropriate flood protection measures.
4. Those federal agencies that tend to be project and developmentally oriented, as opposed to regulatory, are very well suited to implementing ecological projects, e.g., the COE provides cost shared planning assistance to states upon request and allows regional analyses to be undertaken. Further, the interdisciplinary nature of the Coastal America Partnership can provide for the comprehensive examination of coastal problems.

Los Manchos Mangrove Restoration, PR

This $1.6 million project lies within the Los Manchos Mangrove Forest, which is composed primarily of black mangrove, Avicennia nitida, with some fringing red mangrove, Rhizophora mangle. The project involves the restoration of tidal flushing to approximately 1000 acres of mangrove forest along the eastern coastline of Puerto Rico, at the U.S. Naval Station, Roosevelt Roads.

Prior to the restoration efforts, the existing mangrove forest had shown signs of stress due to the blockage of four pre-existing natural channels which had stopped tidal exchange along the eastern boundary of the forest. These historic channels were open to the sea prior to the construction of a two mile long road to the Small Arms Range on Roosevelt Roads in the late 1940's. Later, an attempt was made to increase the flow of seawater by placing culverts beneath the road; however, most were inadequately sized and poorly placed. The last open culverts became completely restricted following Hurricane Hugo in 1989. Hurricane Hugo also caused significant wind related damage to the mangrove forest, which in combination with the lack of salt water exchange, is compounding the mangrove's decline in quality and size.

Currently, there are several steps being taken to restore the Los Manchos mangrove forest. An environmental assessment of the area has been conducted by a private contractor, "Geomarine", and includes hydrologic studies, aerial photographic coverage, and field reconnaissance of the area. Construction phasing of the project, which will be led by the COE with assistance from the U.S. Forest Service includes: the demolition of existing causeways; construction of a new causeway with bridges to allow greater tidal flow and saltwater exchange; and the clearing of damaged and fallen mangroves that are restricting existing culverts. The Puerto Rico Trust will be involved in the planting of new mangrove plants in areas that were severely damaged. Technical assistance for a number of phases of this project are being provided by the Universities of West Virginia and Puerto Rico, the EPA and the FWS.

Galilee Bird Sanctuary, RI

In 1992, the Rhode Island Division of Fish, Wildlife and Estuary resources requested the COE to act as the federal lead in the restoration of tidal flows into a portion of the salt marsh at the Galilee Bird Sanctuary, Narragansett, Rhode Island. Historically, the 128 acre Galilee Bird Sanctuary was mostly salt marsh. However, the placement of fill material from navigation projects adjacent to the marsh and the construction of an escape road through the middle of the marsh complex has significantly restricted tidal flow. Prior to the initiation of this restoration project less than 20 acres of salt marsh and open water existed within the sanctuary, of which only nine acres was vegetated salt marsh supported by adequate tidal flow.

Up to one-half of the sanctuary qualifies for salt marsh restoration under the authority of Section 1135 of the Water resources Development Act of 1986 (WRDA, 1986), which allows the COE to modify existing project operations or features to improve the environment. The remaining half of the site will be restored under the program authority of the State of Rhode Island. However, the overall design and implementation of the restoration will be closely coordinated. Maximum allowable water levels on site were governed by acceptable flood risks to neighboring properties and the presence of two active dredged sediment placement sites which diminished the area available for restoration. Of the total restoration acreage, 2 acres will consist of intertidal habitat within tidal channels, 24 acres will be fully restored to salt marsh and 8 acres will be partially restored to salt marsh. The area will be restored by re-excavating natural channels and installing twin box culverts beneath the escape road to improve tidal exchange.

The COE is contributing $850,000 under its Section 1135 Program which represents 75 percent of the project costs. Local partners include the Rhode Island Department of Environmental Management, which is contributing 25 percent of the cost ($350,000), and the Rhode Island Department of Transportation which has agreed to construct another project's required mitigation feature on site. The EPA is contributing funds under a Clean Water Act Section 319 Grant and, together with the NMFS, is providing technical assistance and consultation. The FWS and Ducks Unlimited are also contributing funds to this effort.

Sagamore Salt Marsh Restoration, MA

In 1990 the Cape Cod Commission identified from 300 to 500 acres of salt marsh in the Sagamore area as degraded due to significant fire damage caused by the presence of dense monotypic stands of the common reed, Phragmites australis. In conjunction with restricted tidal flows, this salt marsh has significantly degraded ecologically and become a breeding ground for mosquitoes. The state requested that the COE, using its authority under Section 1135 of WRDA 1986, modify the Cape Cod Canal structure to increase tidal flushing of the area. The COE is providing 75 percent of the funding for this project in partnership with the Massachusetts Executive Office of Environmental Affairs, which is contributing the remaining 25 percent of the costs. The complex hydrology of the Sagamore salt marsh has increased the up-front planning costs. An analysis of the potential for introduction of saline waters into a fresh water aquifer, residential flooding, and interference with septic systems will require in depth evaluations prior to initiating the ecological restoration of this major salt marsh. NOAA, EPA, and the FWS are providing technical support activities and may provide additional funding, which collectively will aid in the restoration of the 300 to 500 acres of salt marsh adjacent to Scusset Beach State Park.

Lost Creek Restoration, FL

The project site is a salt marsh complex located between Lost Creek and the Halifax River northwest of Ponce Inlet along the Atlantic Intercoastal Waterway, in Volusia County, Florida. Sometime before 1943, sediments from the dredging of the Intercoastal Waterway were deposited in such a way that they completely blocked a natural tidal creek, i.e., Lost Creek, and isolated approximately 200 acres of adjacent salt marsh. The original dredged sediment island at the mouth of Lost Creek has been expanded considerably and has served to further isolate a section of Lost Creek from the main stream body. The isolation of the creek and lack of tidal flushing resulted in an increase in siltation, decreasing the creek's depth to between two and three feet. Additional impacts to the salt marsh complex have included the loss of nearly 225 acres of productive low salt marsh, frequent fish kills during the summer months when dissolved oxygen is low, and a constant state of semi-high tide which altered the natural tidal regime.

The original plan for the salt marsh complex was to use the COE engineering expertise to re-establish the connection between Lost Creek and the Halifax River using drag line equipment to restore creek contours that would closely match the original creek's contours. The COE was to use the authority of Section 1135 of WRDA 1986. However, independent from this project, the Volusia Country Mosquito Control Agency, in order to reduce the breeding of mosquitoes in the area, cut small channels through the salt marsh. Unexpectedly, these small channels have remained open and as of early Spring, 1995, have grown to allow a semipermanent connection between the Lost Creek area and the Halifax River. The COE and its other partners have now surveyed the area and have determined that the proposed project is no longer necessary in the near future.

Technical Lessons Learned:

1. Bridge crossings, culverts and tide gates, if properly designed to consider the hydraulic requirements of adjacent tidal wetlands, do not have to restrict tidal flows to the extent that they negatively impact existing wetland systems.
2. Concerns related to residential flooding, especially impacts to septic systems as a result of increased tidal flows, can be alleviated by encouraging an active public involvement program beginning with a public meeting to initiate the investigation. Flapgates and floodgates may be necessary to protect against significant flood events potentially impacting residential and commercial facilities adjacent to the restoration site.
3. Aerial photography is a good screening tool for identifying degraded wetland sites in large watersheds and estuarine areas, as the unique photographic signature of Phragmites australis has shown in the Northeast. Using older photography is particularly helpful in determining whether a predisturbance marsh type was in fact salt marsh. Where predisturbance marshes were brackish to fresh tidal however, the salt concentration of increased flooding will not be enough to replace existing stands of Phragmites australis, thus, other methods of removal must be examined.
4. An analysis of the potential for introduction of saline waters into a fresh water aquifer, residential flooding, and interference with septic systems all require in depth evaluations prior to initiating the ecological restoration of a salt marsh via increased tidal flows.

Procedural Lessons Learned:

1. The occurrence of natural disasters may provide opportunities to undertake collaborative environmental restoration projects and simultaneously rehabilitate damaged infrastructure with replacement features that are more environmentally compatible.
2. The support of the Coastal America partners makes it possible to address the needs of the overall project. In the case of the Sagamore salt marsh project, the DOT was allowed to delay implementation of off site permit mitigation requirements and incorporate those requirements into the implementation of the overall Coastal America project.
3. The narrowness of some individual agency programs can be enhanced by the Coastal America partnership. For example, with the Galilee Bird Sanctuary project, the COE could not add an interpretive feature to the restoration site; however, the FWS agreed to fund this and other features that collectively enhance the project, thus establishing "value added."
4. The success in other Coastal America projects within neighboring states was the basis for a meeting where the Sagamore salt marsh project in Massachusetts was originally identified. Thus, the ability to promote Coastal America's accomplishments to other potential partners provided the basis for new activities, i.e., nothing promotes success like success.
5. Some Coastal America participants find the Section 1135, WRDA 1986 program to be "maligned in bureaucracy." The associated paperwork requirements and project delays have been disenchanting to local sponsors; however, recently instituted administrative procedures, as of 27 April 1995, for the Section 1135 program should improve its efficiency and acceptability to non-federal interests.

Continue with Subsection A Project Summaries