Wetlands

Wetlands are some of the most valuable and yet most overlooked resources in our country. For years, we have drained, cut off, and destroyed wetland areas to provide more farmland, flood control, or recreational facilities. Wetland acreage has shrunk drastically in the past 100 years, but some progress toward restoring these resources is being made.

Wetlands are valuable as habitat for wildlife, fish, and birds; as protection from storm surge; and as recreation areas. Half of the population of the United States lives along the coasts, where many marsh and wetland areas are affected, but, as well as along the seacoasts, many wetland areas occur naturally in other parts of the country.

Losing Louisiana
Louisiana has the largest coastal wetlands in the United States. The state also accounts for about 90% of the coastal marsh lost each year in the US. Approximately 70% of waterfowl species migrate through Louisiana, and loss of habitat affects their numbers. The fishing industry in Louisiana is the largest in the lower 48 states, and this industry relies heavily on wetland habitat. Since the 1930s, Louisiana has lost 1.2 million acres of wetlands. In the 1970s, the loss was calculated at 25,200 acres per year. By the 1990s, conservation efforts had slowed the loss to 15,300 acres per year, and the estimate for 2000 on was 6,600 acres per year. The challenge is to decrease these losses even more and to restore damaged wetlands.

Constructed terraces and wetland vegetation from the air

Reasons for losses include natural and manmade factors, and many areas must be considered to prevent further destruction. After the recent hurricanes, many area residents contended that previous loss of wetlands and barrier islands increased the damage. Studies are being conducted to see how this can be prevented in future storms. Human factors can drastically change the hydrology of an area, affecting the wetlands. As an example, levees along the Mississippi River provide flood protection but also prevent sediment buildup essential for wetland health.

The Coastal Wetlands Planning, Protection and Restoration Act (CWPPRA) was passed by Congress in 1990 to address these issues. Also known as the Breaux Act, this law has supported more than 150 projects around the country, especially in Louisiana.

Wilco Industrial Services Inc. in New Roads, LA, and its sister company, Wilco Marsh Buggies in Harvey, LA, are one of the leading wetlands restoration outfits in the Gulf Coast region. Executive Vice President Micheal Johnson notes that the companies have been involved in numerous restoration projects.

One project was carried out on and near the Rockefeller State Wildlife Refuge in Cameron and Vermilion parishes. The project goal was to restore intermediate and brackish marshes. High water levels were found in the Lakes portion of the project, due to a highway and a gate and locks system designed to prevent flow of saltwater into nearby lakes. Another sub-basin, the Chenier, suffered from high salinity, and that caused loss of marsh habitat.

Wilco Industrial dredged the existing shallow water canal and installed four 42-inch pipes to provide water control in both directions. This technique gives control of both water level and salinity by allowing the flow direction to be driven by current conditions.

The next step was the installation of 26,000 linear feet of earthen terraces. The terraces trap sediment, creating a marsh area, and reduce erosion caused by wind-driven wave action. Wetland vegetation was planted on the terraces. Construction of the terraces provided about 14 acres of marsh.

A joint project between Wilco Marsh Buggies and Dredging Supply Co. of Reserve, LA, produced an innovative piece of equipment. One disadvantage of the bucket dredge is that as a channel is dredged and the sediment is piled on the bank, the channel is deepened. To keep this from happening, the refuse can be trucked away, but this involves high transportation costs and the need for a disposal area. The Amphibian Spray Dredge disperses the sediment over a larger area, depositing only small amounts in any one place. This dredge is also built to be used in shallow water and minimizes impact to the ecosystem.

Industrialized Massachusetts
Chelsea, MA, is one of the most urbanized towns in the United States. Local officials contacted the National Oceanic and Atmospheric Administration (NOAA) to propose a wetland restoration in the area. Mill Creek, the headwaters of Chelsea Creek, is Chelsea’s only remaining salt marsh and only site not designated for industrial use. A section of the heavily industrialized creek was chosen as a pilot site for wetland restoration. The 0.75-acre site is surrounded by a shopping mall, public housing, and a busy highway.

The Chelsea Green Space and Recreation Committee, NOAA, the City of Chelsea, and other local, state, and federal agencies and corporations came together to restore and maintain the wetlands.

According to Eric Hutchins, National Marine Fisheries habitat restoration coordinator, the first step was to persuade the Highway Department of its responsibility in the project. Stormwater runoff from the highway was piped into the salt marsh and sediments were clogging the marsh. In some places, the sediment was 5 feet deep. Debris such as shopping carts and trash also littered the marsh.

The Corporate Wetlands Restoration Partnership, pioneered in Massachusetts, led the way for this project. Local communities lacking matching funds depend on private companies to provide money. For the Mill Creek Restoration Project, five companies donated money or services, predominately in in-kind donations. Eastern Analytical offered sediment sampling; Charter Environmental handled the excavation; Waste Management waived many of its fees to truck the contaminated sediment away; ERM coordinated sediment sampling; and BSC Group took on permit coordination. Without the donations of these companies, the project would not have been feasible.

Before the project began, the grade of Mill Creek had built up to a high enough level that only two tides a month arrived in the upper reaches. Many sections received water only during stormwater events, so no fish could survive in the environment. The animals seen in the area were rats and skunks. The plant life was almost entirely invasive species.

The surface grade was reduced by 6 to 12 inches, allowing daily tidal flow. Pannes and pools were incorporated in the design to encourage diversity of wildlife, such as salt marsh minnows. Approximately 1,200 cubic yards of invasive plants were ripped up and disposed of. Planting of native species will occur in spring 2006.

Education of schoolchildren and nearby residents increases the likelihood that they will value the wetlands and fight to keep the area healthy. Schoolchildren are monitoring water quality and soil salinity levels and observing diversity of wildlife.

The project appears to be healing the marsh. Egrets and great blue herons have been sighted.

Going Natural in Virginia
In 1995, the EPA, the Natural Resources Conservation Service, the Fish and Wildlife Service, the Army Corps of Engineers, and NOAA issued “Federal Guidance for the Establishment, Use and Operation of Mitigation Banks.” This document has provided the guidelines for wetland mitigation banks. Marsh Resources Inc. is one of the largest mitigation banks, and it has contracted with Greenhorne & O’Mara Inc. for several projects in Virginia.

James Ingram, senior environmental scientist for Greenhorne & O’Mara, has managed several of the projects in the last six years, working in almost every Potomac watershed in Virginia. As project manager, Ingram identifies the potential mitigation sites, negotiates with landowners and drafts option agreements, performs technical studies and testing, and designs the project. The technical studies include Section 106 clearance with the state historical office because of possible artifacts from Civil War battles or earlier times.

Once a site has been identified, Ingram negotiates with landowners for either easement for the project or purchase of the site. Most of the areas were historically wetlands that have been drained by farmers. Some still are so wet most of the year that farmers use them as “summer pasture” during July, August, and September, the only months they are dry enough. One site that Ingram recently bought flooded frequently, and stormwater had deposited woody debris. The conditions made the site difficult for the farmer to use but invaluable as wetlands.

Extensive onsite soil testing provides clues to the historical wetland properties of each site. Ingram says he believes in doing minimal work to undo what human activity has done to a site over the last 200 years. If the right site is chosen, “We don’t do a lot of earthwork,” he says. Minimal disturbance will push a site back to wetland status. “The less push needed, the better the site is.”

Farmers have often dug ditches or installed French drains on the upland side of a property to handle the seepage. Ingram says that by choosing sites that were once wetlands, the areas can be restored easily. For many sites, simply installing ditch plugs provides the needed water for wetland restoration.

Another technique used in the restoration process is root raking. Removing the turf layer and restoring hydrology exposes seed banks, and native herbaceous plants begin to grow. For most projects in Virginia, trees and shrubs are planted to restore those species, but other seeds are present already.

Once plant life has been restored, animal life follows. Amphibians, eagles, coyotes, fox, deer, and wood duck return to the wetland. One benefit of the approach, according to Ingram, is that these areas with tall plants are not attractive to Canada geese, a nuisance species for the region. Canada geese require large open spaces, which are not found in these wetlands. The habitat is more conducive to wood ducks and other native birds.

Working with Ingram on several projects was Gary Jellick of Acorn Environmental Inc. The Bender Farms project involved an active dairy farm. Cows roamed near and in the stream, Cedar Run, and sediment flowed into the creek during storms. For the farmer, the wet field was more trouble than it was worth, according to Jellick. The EPA requested that some pretreatment be done for the water before it entered the wetlands that were being restored, so a ponded area was created to capture the first flush of stormwater. Shrubby plants, such as buttonbush, were planted to increase the uptake of the nutrient load. The pond is only about 6 inches deep to provide a good growth environment for the shrubs. Two outlets at grade level of the pond provide overflow into the wetlands during rain events. The setup mimics natural wetlands.

The Howser’s Branch project was undertaken at the request of the Mount Zion Church Preservation group. The property was slated to be developed, but the group wanted to preserve the church and have a place for cavalry reenactment troops to practice. They sold an easement for 45 acres of floodplain that had been used to grow hay. By waiting until the wetland credits through the mitigation bank were sold, they received a higher price for the land. According to Jellick, an acre of wetlands usually equals one credit. If the project is preserving an existing wetland, 10 acres equals one credit; for upland components needed for the project, the amount is 20 acres for one credit. Designs for the project have been submitted to agencies, and construction is to start soon.

Jellick states that the process is all about how much water comes into a site, how much leaves, and how fast. Ingram mentions what he calls “Jellick’s 180 Rule”—you face the stream and then turn around to see what the land 180 degrees away is like—adding, “We let the information confirm the design, not drive the design.”

Dredging From Kansas City
It may seem strange to find a dredging company in Kansas City, MO, but that’s where Dredge America Inc. is located. President Dan McDougal says the advantage is that the company can have a dredge anywhere in the country in about two hours because of its central location. The company owns five portable dredges. One project that Dredge America tackled was on the backside of Galveston Island in Texas.

Wave action was causing severe erosion of the bank, so Dredge America personnel installed 9,000 feet of geotubes to create a backwater. Then marsh buggies were used to create a matrix for plant growth. The area was replanted with wetland plants, and the plant life is thriving. This project was contracted by the Texas Parks and Wildlife Department.

Along the Mississippi Gulf Coast, a wetland channel had filled in with sediment, obstructing flow from uplands into the gulf. Dredge America was contracted to dredge an 8-foot-wide channel. Managing the job without negative impact on the wetlands is the goal of Dredge America. If the project is designed properly with the geotubes placed correctly and the sediment pumped behind them, the wetland area is stabilized even during high tides, according to McDougal.

“Once dredging was seen as a bad thing,” McDougal says. Now people have seen that it can be a useful tool for wetland preservation and restoration. Once dredging is finished, the wetland habitat begins to recover and the number of species just explodes. Dredging can create channels for recreational or industrial use and provide good habitat.

Once the innovative permit was received, NAWE designed and constructed a wetland area to bring it about. Floodplains near the Minnesota River and the Cottonwood River had historically functioned as forested wetlands. These areas, 40 and 110 acres in size, would trap and store water during the spring runoff. The land had been converted to row crops, primarily corn and soybeans. A study by the Corps of Engineers showed that in past years, 3 feet of topsoil had been lost during flood events. At the beginning of the project, a major flood had scoured holes in the ground.

Some minor grading started the project, mostly to fill the scour holes. Hybrid poplar cuttings were planted as a living picket fence. A variety of native wildflowers and grasses was planted in the area. Not only did the project meet the trading program parameters, but during a flood event three years ago, the area did not lose any additional topsoil. Instead, sediment was deposited there, keeping it out of the rivers.

Since 1997, the project has continued to fulfill its function as a wetland area. Rahr Malting was awarded a Minnesota Environmental Initiative Award for its effort to improve river water quality.

Another NAWE project includes education of schoolchildren. The Indian Creek Nature Center in Cedar Rapids, IA, is visited by about 10,000 schoolchildren each year. One area of the Nature Center was a historical wetland that had been drained during construction of the Transcontinental Railroad. NAWE restored the wetland by diverting Bena Brook into the area and then into the Cedar River. Underwater species, tall grass prairie plants, and sedge meadows were planted, and the area has been used as a reintroduction site for the grass pickerel fish species. Because the area matched the fishes’ natural habitat and provides a section isolated from the river with protection from predator species, the pickerel have thrived.

Wallace says the ultimate driving force behind wetland restoration is the acknowledgement that water needs to be stored and the quality needs to be improved. One of the best ways is through wetlands. His company prefers to build 1,000 wetlands of 100-acre size rather than huge 100,000-acre sites. The split between restoration and creation of wetlands by NAWE is about 50-50. Some projects in developed areas or brownfields must be created wetlands, while other sites that were historic wetlands need only a little encouragement to return to that state. The created wetland projects mean starting from scratch and often require harder work and more extensive grading.

Louisiana Damage
Plaquemines Parish, LA, was right in the center of Hurricane Katrina. Most of the wetland projects suffered some damage, according to Andrew MacInnes, GIS manager and coastal zone administrator for the parish. The barrier shorelines were especially hard hit, and wetlands that included only such natural elements as a cut through a riverbank show significant damage. Other projects constructed of more durable materials fared better.

A siphon system at the community of West Pointe a la Hache had significant damage. Eight pipes divert water from the Mississippi River, over the levee, and into a wetlands outfall. The wetlands receive inundating water when the river level is high, and that helps decrease the salinity. The infrastructure of the siphons is torn up because of the hurricane, and the outfall received some damage. Some of the marsh washed out, but because winter is the dry season, the siphons will likely be replaced before needed in the spring.

A project constructed by Wilco Industries for the parish included building 150 earthen terraces near Alexis Bay. The terraces had just been finished in July 2005, and 1,000 container plants had been placed around the terrace perimeters. Hurricane Katrina did some damage to the project; some terraces were washed away, but others only sustained minor hits. MacInnes thinks once wetland vegetation is in place on the tops of the terraces they will fare better in another storm. The planting will take place in spring 2006. Despite the damage that occurred, he was pleased that the terraces were able to withstand so much punishment.

Wetlands will continue to be a valuable resource, and they need to be built, restored, and protected. “We need to build more projects and more quickly,” says MacInnes, adding that the dispersed patchwork of projects in southern Louisiana is not enough to adequately protect the wetland environment. One positive effect of the recent spate of hurricanes might be to focus attention on the wetlands and what they need to thrive.