In Baltimore, MD, multi-disciplinary architecture firm Ayers Saint Gross has completed the National Aquarium Harbor Wetland. Ayers Saint Gross worked with the National Aquarium to develop this first-of-its-kind, sustainable, high-performing floating wetland intended to restore natural habitats and significantly improve biodiversity and water quality, reversing years of environmental degradation while creating a renewed, thriving ecosystem.
With a prime location in Baltimore’s Inner Harbor between Piers 3 and 4, The Harbor Wetland is a free exhibit on the National Aquarium campus. Over the 10,000-square-foot habitat, visitors can immerse themselves in a salt marsh habitat like those that existed in this space hundreds of years ago.
Featuring over 30,000 grasses and shrubs combined with water aeration technology, the design differs from conventional systems by introducing a new kind of floating wetland with layered topography and planting surfaces at tiered elevations to promote a variety of microhabitats and attract a greater diversity of species to the area. It also features an adjustable—rather than static—buoyancy system that is essential to promoting greater longevity.
Harbor Wetland is a functional constructed wetland. The habitat is made up of recycled plastic matting planted with tidal wetland shrubs and grasses native to the region whose roots will grow down into the water. The roots will provide microhabitats for dozens of native species and draw nutrients and contaminants from the water. The matting is coated with a UV protectant for durability and fixed to a system of air-regulated pontoons that allow for adjustable buoyancy of the wetland to offset weight gain from the growing biomass.
Water circulated through the wetland’s shallow channel by compressed air pumped into the channel using strategically placed airlifts. Compressed air is supplied to ceramic airstones positioned at the bottom of custom-designed six-foot-long airlift pipes. Thousands of tiny bubbles produced by the airstones rise to the surface, moving water through the wetland’s shallow channel. Bubbles also release oxygen into the surrounding water, benefiting aquatic species by raising dissolved oxygen levels and keeping water moving throughout the wetland during tidal changes in a natural tidal marsh.
The Harbor Wetland project was born from an earlier Waterford Campus Plan, also completed by Ayers Saint Gross. That project led to the design of a Floating Wetland Prototype, on which Ayers Saint Gross worked with the National Aquarium and Biohabitats, McLaren Engineering Group, and Kovacs, Whitney & Associated in continuation of Studio Gang’s EcoSlip concept. The knowledge gained from years of studying and refining the prototype became the basis for the design process of the implementation of the full-scale Harbor Wetland.
The wetland is already attracting wildlife, including river otters, fish, ducks and Maryland blue crabs.
