8,000 square foot Inner Harbor Wetland attracting nature to downtown

Charmaine Dahlenburg, Director of Conservation at the National Aquarium took us on a tour or their wetland project. It's been going on for over ten years, seeing several variations in structure and content of floating platforms that helps bring the natural environment that once existed in Baltimore's Inner Harbor back to life.

"It takes a little bit of a man and a little bit of nature and putting it together." ​

The Aquarium has used a combination of state and federal funds to build this eight-thousand-foot floating habitat. It's the first of it's kind ​in the United States to be installed in a tidal area. Dahlenburg tells us the technology being used is most often used in retention ponds for developments. But as it turns out, it provides the right kind of waterflow for what she and the team are trying to accomplish.

It's been a bit of trial and error. Their first structure, a two-hundred-foot platform, attracted so much nature it eventually sank. So the team started expanding and adjusting the design to better deal with the site's popularity with the harbor's animal population.

Kristi Harper

Dahlenburg explained that the Inner Harbor was once a brackish tidal marsh made by the mixture of sea water flowing from the Chesapeake and fresh water coming in large part from the Susquehanna River. She said that the specific environment was why the area was so attractive to not only wildlife, but Baltimore's original inhabitants.

"But with all of our urbanization and our development a lot of those tidal wetlands have been lost." ​

That loss is important because wetlands clean our water.

​ "The Chesapeake Bay has three major pollutants that we're concerned about. Nitrogen, phosphorus and sediment. People really flocked to Baltimore because of the water source. Because there were um abundance of oysters and striped bass and everything like that. And unfortunately, we saw a lot of decline of that as our economy grew." ​

That growth overwhelmed this natural resource but efforts like the harbor wetlands seek to bring the balance of human and nature back.

But how exactly does the habitat clean the water? Dahlenburg says the two native grasses they've planted take up pollutants and provides a home for wildlife. Conservationists have also allowed biofilms to flourish on the structures.

That's the slimy stuff you see just under the water's surface on many harbor structures. That biofilm provides a food source for mussels, barnacles and small worms that filter harmful pollutants from the water. But the key is balance. While walking around the habitat Dahlenburg pointed out just some of the trash they collect daily from the site.

Kristi Harper

Plastic straws, balloons, even a fishing lure that looked dangerously like some of the fish other wildlife love to eat, "So this can be really harmful to birds." ​

The habitat is already attracting wildlife. Faster than the project's goal. Recently, a night security guard got video of two otters playing in the wetland. They've also observed native turtles, herons, frogs and even more fish. In fact, while we were there, we saw a cormorant catch a snack out of the water right behind Dahlenburg.

Above and below, there is a return of many native species, like the Menhaden fish that forage for food while they swim in a beautiful circle formation.

The team of conservationists at the aquarium would love for the public to help. They recommend snapping a picture or getting video if you see a creature in the wetland.

They recommend uploading it to i-Naturalist, a free open-source database for nature observers. This helps conservationists track the progress of restoring the balance of nature and a vibrant downtown.

​ "I don't expect this habitat here to solve all of Baltimore's problems with water quality. But it's one part of that puzzle." ​

In doing our part to keep pollutants out of the water and giving space for nature to do it's part, our city is starting to be healthier for all. The National Aquarium's wetland is free and open to the public during normal business hours starting August 9.