Most of us who live in urban or suburban settings really don’t know what a healthy stream looks like. In some cases, we can’t even see the streams that run under our roads and shopping centers because they’ve been forced into pipes; out of sight, out of mind. The remnants of streams we can see have often been filled with sediment and other pollution, their ecology altered. The plants and animals that used to live there have long since departed, their habitat destroyed. This didn’t happen overnight. The environment is suffering “a death by a thousand cuts.”
I recently got the chance to visit the Cabin Branch stream restoration project, not far from my neighborhood in Annapolis, Md. The project is being undertaken by Underwood & Associates on behalf of the Severn Riverkeeper Program, and is one of many stream restoration projects taking place across the Chesapeake Bay watershed.
In 2005, a volunteer cleanup removed 40 tons of tires and debris from Cabin Branch. Image courtesy Severn Riverkeeper Program.
Cabin Branch discharges to the streams and wetlands of Saltworks Creek and the Severn River, which bring water into the Bay. Aerial photos taken after a modest rain are dramatic testament to a severely damaged ecosystem that causes the Severn to run the color of chocolate milk. This same phenomenon—one of sedimentation and stormwater runoff—is repeated in streams and rivers that run through thousands of communities throughout the watershed.
Image courtesy Severn Riverkeeper Program.
It was gratifying to see the Cabin Branch project firsthand—one of many efforts to heal the damage done unknowingly by many decades of development. Like many projects of this nature, the Severn Riverkeeper Program had to overcome some bureaucratic red tape to get the permits they needed, but their perseverance will be worth the impact in helping clean local waters and the Bay.
Image courtesy Tom Wenz/EPA CBPO.
Fortunately, we are learning better ways to manage stormwater runoff through low impact development and the use of green infrastructure, which help to mimic the cleansing functions of nature. It will take some time before this patient is restored to good health, but we are on the mend.
Part construction site, part mud pit and part wildlife refuge, the Paul S. Sarbanes Ecosystem Restoration Project at Poplar Island, Md., tackles two unique challenges in the Chesapeake Bay.
First, sand and sediment accumulate in the Bay’s vital shipping channels—particularly during heavy rain events like Tropical Storm Lee in 2011—and threaten to block cargo ships that allow the Port of Baltimore to contribute $2 billion each year to the region’s economy.
On the other hand, sea level rise, sinking land and increasingly frequent strong storms are quickly eroding away the Bay’s few remaining islands, threatening the survival of iconic wildlife species and critical habitat.
Poplar Island, for example, spanned more than 1,100 acres in the mid-1800s and supported a small community of families, farmers and fishermen until it was abandoned in the 1930s. When restoration began in the 1990s, four scattered acres were all that remained—less than half a percent of the island’s historical size.
But the island that was nearly destroyed is now destined to be rebuilt using 65 million cubic yards of sedimentary silt—imagine a giant cube of mud a quarter mile long in each direction—dredged up from the bottom of the Bay.
In 1998, the U.S. Army Corps of Engineers began to construct stone “containment dykes.” The walls are 10 feet tall and surround Poplar Island’s former footprint, and the island has been divided into six massive containment cells for building island habitat.
The western half of the island, surrounded by an inner ring of 27-foot dykes, is being transformed into 570 acres of forested upland island habitat similar to that of neighboring Coaches Island.
Coaches Island, once vulnerable to the same forces that washed away its neighbor, supports upland species like bald eagles and provides a shallow inlet utilized by nesting diamondback terrapins in the summer and migratory waterfowl during winter.
The eastern half of Poplar Island is further divided into 14 “sub-cells” undergoing various stages of wetland construction and management.
Low-lying wetlands are created through a four-step process. First, dredged sediment is brought in on barges by the Maryland Port Administration, mixed into a watery slurry, and pumped into each cell at precise levels.
As the slurry dries, it forms a massive crust—a vast, other-worldly landscape—that is the base for building habitat.
Next, heavy machines carefully grade the crust and excavate ditches that will function as tidal creeks in the completed marsh.
Then a spillway is opened to expose the new landscape to tidal flow, and water is allowed to move between the Bay and the newly built marshland.
Finally, individual plugs of smooth and saltmeadow cordgrass are planted row upon row into the nutrient-rich soil.
These native plants are capable of withstanding strong storms while offering food and shelter to the 175 species of shorebirds, songbirds, waterfowl and raptors that now visit Poplar Island.
Poplar Island's marshes offer protection and isolation from human and mammalian predators, and the open waters along its perimeter provide feeding opportunities for diving ducks like buffleheads, scaups and long-tailed ducks.
The U.S. Fish and Wildlife Service (USFWS) manages the island’s vegetation and wildlife—including less welcome species like the Canada goose. Fences and fluttering pink flags help deter geese and prevent them from overfeeding on expensive marsh grass.
On our visit in January 2013, USFWS wildlife technician Robbie Callahan led a monitoring team to assess the density of muskrat huts in the marsh. The semiaquatic rodents, though a critical part of the wetland ecosystem, are controlled to prevent damage from overpopulation.
The USFWS also monitors avian predators—like the northern harriers that feed on small rodents—and migratory waterfowl, attracted to Poplar Island during their spring and fall trips along the Atlantic Flyway.
With the help of USFWS experts, Poplar Island is able to provide a range of Bay species with the safe nesting habitat that only a protected, well-managed island can.
Even sunken barges—placed here in the mid-1990s as “breakwaters” in an attempt to retain the island’s remnants—have become host to nesting ospreys and black-crowned night herons.
According to the USFWS, Poplar Island is well on its way to becoming a keystone wildlife refuge. “Poplar Island is an important refuge,” said USFWS biologist Pete McGowan, who specializes in waterfowl and island restoration. “There are species that are highly dependent on these remote island habitats. And this is a habitat type that is rapidly disappearing from the Chesapeake Bay. We need to do what we can to maximize the remaining island habitat that we have, and create new island habitat whenever possible.”
The Paul S. Sarbanes Ecosystem Restoration Project is scheduled for completion in 2041, with a final price tag estimated at $1.4 billion over 45 years. Rebuilding Poplar Island is an enormous, expensive and painstaking process—but its virtues of “beneficial use” have been extolled throughout the conservation and business communities alike, and it has become a "win-win" for the Bay and all the watershed provides.
View more photos on the Chesapeake Bay Program Flickr page.
The District of Columbia has outlined the steps it will take to become the healthiest, greenest and most livable city in the United States.
The Sustainable DC Plan, released this week by the District Department of the Environment (DDOE) and Office of Planning (OE), sets forth more than 100 actions that are meant to improve the District’s energy consumption, waste generation, stormwater management and access to open spaces, clean water and fresh, local food—all in just two decades.
At an event that celebrated the release of the plan, District of Columbia Mayor Vincent C. Gray called Washington, D.C., a “model” of sustainability for cities across the nation and around the world.
“Things are changing. Times are changing. And we are changing,” Gray said.
In recent years, the District has become a leader in planting trees, installing green roofs, boosting public transportation and curbing greenhouse gas emissions.
The Sustainable DC Plan will build on these actions with ambitious goals to clean up local land, water and the Chesapeake Bay. The District will ensure, for instance, that all residents live within a 10-minute walk of parks or natural spaces; that 40 percent of the city is covered with a healthy tree canopy; and that all of the District’s waterways—including the long-polluted Anacostia River—are made fishable and swimmable by 2032.
Read more about the Sustainable DC Plan.
On private piers up and down Harris Creek, hundreds of metal cages hang from ropes into blue-green water. Inside each cage are countless little oysters, which will grow here, safe from predators and sediment, during their first nine months of life. Once the spat are large enough, they will be pulled out of their short-term shelters and put onto boats to be replanted on protected reefs just a few short miles away.
The cages—along with the bivalves inside them—are cared for by volunteers with the Tilghman Islanders Grow Oysters (TIGO) program, itself a local branch of the Marylanders Grow Oysters program that is managed by the Phillips Wharf Environmental Center (PWEC).
Now in its second season, TIGO has recruited more than 80 volunteers across the so-called “Bay Hundred” region—from Bozman and Neavitt to Wittman and Tilghman Island—to further oyster restoration efforts in the Chesapeake Bay.
Over the past two centuries, native oyster populations have experienced a dramatic decline, as habitat loss, disease and historic over-harvesting have taken their toll. But programs like this one give hatchery-grown oysters a head start before they are put into the Bay to replenish critical underwater reefs.
The TIGO program has attracted a wide range of restoration enthusiasts, from the middle-school student who has tracked her oysters’ growth for a science fair project to the neighbors who have competed against each other to grow more and bigger oysters. The main draw? What little effort is involved.
“Growing oysters is an effort, but it’s a really easy effort,” said TIGO coordinator Carol McCollough. “And we remove as many of the roadblocks as we possibly can for people who want to do this.”
Aside from a promise to keep cages free of excess sand and silt, the program doesn’t ask too much of its volunteers—and this has worked to its advantage.
H. Truitt Sunderland is a Wittman resident whose cages are filling up fast after six months of growth. The oysters have gone from mere millimeters to one and two inches in size, and a host of other critters—like grass shrimp and gobies, mud crabs and skillet fish—have taken up residence on this makeshift reef just as they would do on oyster bars in the Bay.
Sunderland’s home sits on Cummings Creek, and Sunderland has used the ease of the work involved—“I don’t even know how they can call this volunteer work,” he laughed—to involve his neighbors. Now, there are 24 cages on 12 piers in this single stretch of water.
Tilghman Island resident and fellow volunteer Steve Bender has had a similar experience. “The process is simple,” Bender said, standing on a wooden pier that juts into Blackwalnut Cove. “It’s not that demanding. It’s not that difficult to care for [the oysters].” And in response to his encouragement, Bender’s neighbors have been “glad” to join.
While projects like this one are a small drop in the restoration bucket, McCullough hopes that TIGO can cast a personal light on conservation for all those who are involved.
“We [at PWEC] inform, inspire and involve,” McCullough said. “We’re all about getting people to commit to [changes in] behaviors. It’s very easy to give money. It’s less easy to write letters. And I think in many ways, it’s even less easy to do something personal—to do restoration work on your own.”
But for McCullough, it’s possible that the simple act of caring for a cage of oysters could act as a stepping stone toward further involvement in the Bay.
“Oysters have become very exciting to people,” McCullough said. “They recognize that every single additional oyster in the Bay is a positive thing. That oyster restoration is something that’s bigger than they are.”
For more photos, visit the Chesapeake Bay Program Flickr page.
Photos by Multimedia Coordinator Steve Droter.