Artificial wetlands restored floating on water
In Baltimore’s Inner Harbor, a 930m² artificial wetland has been created to replicate the salt marshes that existed centuries ago. The ‘Harbor Wetland’, located between Pier 3 and Pier 4 adjacent to the National Aquarium, expands the natural habitat in the area and introduces a new landscape. First established in 1873, the National Aquarium operated for over a century before facing closure. However, it reopened at Pier 3 in the 1970s as part of the harbor’s redevelopment efforts and later expanded to Pier 4. The wetland is accessible to the public via a floating walkway that connects the two piers, offering a unique experience of walking over the water.
The wetland is home to over 30,000 native shrubs and grasses, which take root on recycled plastic mats. These mats provide a habitat for dozens of native species to survive, as well as providing beneficial nutrients and filtering pollutants from the water. The mats are secured by an air-regulated pontoon system, which keeps them floating stably on the surface. The top layer of the mats is coated with a UV protector for durability. Compressed air flows through shallow water channels in the wetland, releasing small bubbles that rise to the surface, oxygenating the water. This process mimics the natural tidal movements that regulate water flow in natural wetlands.
Already, the wetland has become a gathering spot for fish, mollusks, and seabirds. With elevated walkways, benches, and shaded areas, it also serves as a popular destination for visitors. Baltimore’s Inner Harbor has now become a new green infrastructure in the city, drawing both wildlife and people. Over time, as the plants grow denser, the wetland will evolve into a healthier, cleaner aquatic environment and a safe, vibrant habitat.
Project: National Aquarium Harbor Wetland / Location: Baltimore, United States / Architect: Ayers Saint Gross / Project team: Ayers Saint Gross / Use: Landscape Architecture / Site area: 929.03m² / Completion: 2024 / Photograph: ©Philip Smith (courtesy of the architect)
