Floating Wetlands Bring Nature Back to Baltimore’s Inner Harbor

Harbor Wetland at National Aquarium, Baltimore, Maryland. Ayers Saint Gross / Phillip Smith, courtesy of National Aquarium

The National Aquarium’s new Harbor Wetland shows the great potential of creating wildlife habitat in cities. With just 10,000 square feet, it has already drawn otters, herons, ducks, crabs, fish, eels, and jellyfish.

Harbor Wetland at National Aquarium, Baltimore, Maryland. Ayers Saint Gross / Phillip Smith, courtesy of National Aquarium

The $14 million constructed wetland in Baltimore, Maryland was designed by landscape architects at Ayers Saint Gross, a multidisciplinary firm. It improves the harbor environment and advances research and innovation. It’s also a free educational landscape that inspires the public to reconnect with nature.

“Harbor Wetland is an example of how to marry science and art,” said Amelle Schultz, ASLA, PLA, a principal and landscape architect with Ayers Saint Gross. “It leaves no doubt that landscape architecture is a STEM discipline.”

Schultz said the floating wetland may look simple but in reality it’s a complex work of design and engineering. “Only about one-third of the project is visible; two-thirds is below the surface.”

Harbor Wetland at National Aquarium, Baltimore, Maryland. Ayers Saint Gross / Phillip Smith, courtesy of National Aquarium

The wetland has many layers. More than 32,000 native tidal marsh shrubs and grasses form the top. They were planted in recycled plastic matting that will allow the plant roots to grow down into the water, providing habitat for dozens of species and filtering harbor water.

Harbor Wetland at National Aquarium, Baltimore, Maryland. Ayers Saint Gross / Phillip Smith, courtesy of National Aquarium

Amid these plants are shallow channels, with beds of oyster shells that provide additional habitat. Compressed air is pumped into these channels, bringing dissolved oxygen into the harbor and keeping water circulating, like in a natural tidal marsh.

Harbor Wetland at National Aquarium, Baltimore, Maryland. Ayers Saint Gross / Phillip Smith, courtesy of National Aquarium
Harbor Wetland at National Aquarium, Baltimore, Maryland. Ayers Saint Gross / Phillip Smith, courtesy of National Aquarium

This entire system sits on top of another layer of custom pontoons. Their buoyancy is adjusted as the weight of the wetland increases with plant growth. The pontoons also support the walkways and outdoor classroom spaces that line the installation. “Traditional constructed wetlands eventually sink under their weight — this one won’t,” Schultz said.

Sitting at the end of the classroom space, hundreds of feet into the harbor, there is a moment of serenity. It’s easy to forget about all the engineering and technology and just imagine you are in a natural wetland.

Harbor Wetland at National Aquarium, Baltimore, Maryland / Jared Green

And the project also makes it easy to imagine more wetlands. The project supports the aquarium’s long-term ecological research and will inform the creation of future constructed wetlands. The system is designed to help make the case: Sensors embedded in the wetland test the water quality, and researchers are documenting species populations.

Schultz thinks one measure of the project’s success is the incredible range of species that now visit. “The aquarium’s interior exhibitions are built to be natural, but the animals can’t leave. The animals that visit the wetland choose to be here,” she said. Some of the species that visit were a surprise: “American eels are really hard to find in the harbor.”

The grasses are important habitat for many species the aquarium wants to track. As they were growing in, the aquarium even added a plastic coyote to scare off geese, which would have made a meal of them. “It’s more of a joke now than a deterrent,” said Shelley Johnson, ASLA, PLA, senior associate with Ayers Saint Gross.

Harbor Wetland at National Aquarium, Baltimore, Maryland / Jared Green

Harbor Wetland also builds on research conducted on a smaller prototype just a few feet away in the same bulkhead, which was initiated more than 10 years ago. Ayers Saint Gross worked with Biohabitats, McLaren Engineering Group, and Kovacs, Whitney & Associates to advance an initial concept created by Studio Gang.

National Aquarium wetland prototype, Baltimore, Maryland / Jared Green

“Even in the prototype, the aquarium team saw small fish come to the small stream in the middle of the wetland. No one expected that to happen,” Schultz said.

The aquarium thinks Harbor Wetland will boost the local economy. “The wetland will bring more people to the inner harbor,” Johnson said. “Not everyone can afford tickets to the aquarium, but they can visit this.”

School groups are already visiting, where they are given tours by aquarium researchers. The mural that frames the project expresses the aquarium’s hope that more young people in Baltimore will be inspired to join the effort to restore the Chesapeake Bay.

Harbor Wetland at National Aquarium, Baltimore, Maryland. Ayers Saint Gross / Phillip Smith, courtesy of National Aquarium

“Landscape architects led the team to the solution — the technical and scientific aspects, and married that to the public realm,” Schultz said.

The technical work alone realized benefits: their innovations led to a new patent application focused on the integrated buoyancy and aeration system.

Co-Creating a Future That Heals Land and Culture

Bison in Yellowstone National Park / Fokusiert, istockphoto.com

“Indigenous Peoples were the first landscape architects of this continent,” said Lyla June Johnston, during the opening general session of the ASLA 2024 Conference on Landscape Architecture in Washington, D.C. “We have been stewards of this land and made it beautiful and edible. We fed the Earth instead of just letting it feed us.”

Chestnut forests once spanned the east coast from Maine to Georgia, before a blight decimated the trees. “These were not wild forests, but planted by Indigenous Peoples. And Native land stewards evolved those landscapes over time.” Scientists know this from studying soil core samples and fossilized charcoal going back 10,000 years. The data shows that chestnut and hickory trees dramatically spiked 3,000 years ago, and black walnut 2,000 years ago.

Chestnut Grove, Virginia / AidanWarren, istockphoto.com

In the Pacific Northwest, there were once vast, cultivated clam gardens. “You can see them from ancient clam garden walls that augmented natural clam habitat.” These gardens were co-designed with clams because “they are equal to us and have their own nationhood status.”

Clam garden in the Broughton Archipelago, British Columbia, Canada / Wikipedia, Simon Fraser University, CC BY 2.0

In the Illinois region, Indigenous People burned prairies for thousands of years to “maximize productivity and regain nutrients,” Johnston said. “Fire brings new life to the prairie. Flowers emerge in the spring.” Ash from fires also nourished soils and created nutrient-rich grasses that made habitat for bison and deer. “Indigenous Peoples passed on this great heirloom for thousands of years to their children— a living soil system.”

In the Washington, D.C. area, Indigenous Peoples cultivated oyster fisheries for more than 3,000 years. Oyster populations of the Chesapeake Bay are less than 1 percent of what once was.

Johnston is an Indigenous Artist, Musician, Scholar, and Community Organizer of Diné (Navajo), Tsétsêhéstâhese (Cheyenne), and European lineages. She argues that land stewardship should be restored to Indigenous Peoples given they are far better at creating and restoring habitat than Western people.

“People can be a gift, not a virus. We can be creators and a keystone species. We can be in service to the land. We can create edible landscapes that support the well-being of all,” she said.

But to become a keystone species and support global regeneration once again, people need to “first landscape their inner world before they landscape the outer world.” Our global society needs to shift its mindset. Instead of exploiting nature, we need to be its guardian. “Think of a bird bath — it’s not for us, but lets birds rest, drink, and bathe.”

Johnston argued that communities could give more land back to Indigenous Peoples because their guardian mindset is so crucial to protecting biodiverse places and restoring them. “Worldwide, Indigenous Peoples are 5 percent of the population but we manage 80 percent of global biodiversity. Give us more land to manage. We are good at this.”

Johnston was followed by Julia Watson, Author, Lo—TEK Design by Radical Indigenism; Principal, Julia Watson llc; and Co-founder Lo—TEK Institute. She understands traditional ecological knowledge as “inter-related networks of knowledge.”

After many years of working with Indigenous communities and designers, “I came to understand this knowledge is relational and shaped by time and place. It’s different from Western science; Indigenous knowledge is interconnected.”

“There are vast networks of knowledge developed over long periods of time. These networks of knowledge enabled ancestral people to survive and adapt to climate change over thousands of years. You can’t separate their technologies from the people; they are co-evolutionary.”

Watson offered an example: the sea fishing techniques of the Yap people of Micronesia. They created artificial reefs and weirs that catch fish in the outgoing tides. “The technology is 1,000 years old.”

Aech Fish Weirs of the Yap People of Micronesia / Bill Jeffrey, courtesy of Julia Watson
Aech Fish Weirs of the Yap People of Micronesia / Bill Jeffrey, courtesy of Julia Watson

With the colonization of the region, this Indigenous technology was no longer used for fishing. But even after falling into disrepair, the legacy of the infrastructure forms breakwaters that protect these communities today.

Watson said these systems can be brought back along with other traditional ecological knowledge (TEK) systems created by Indigenous communities around the world.

After the success of her book Lo-TEK, Watson has written a follow-up – Lo-TEK: Water, which focuses on ancestral aquatic technologies. It will be released in the spring of next year. The new book includes 22 case studies of traditional infrastructure and 22 contemporary projects infused with TEK that “rebuild ancient knowledge and highlight Indigenous traditions of adapting to climate change.” She organized these technologies in multiple categories: living, co-evolutionary, sovereign, symbiotic, and cyclical.

Watson’s goal is to bring ancestral technologies back into the global discussion about solutions to the biodiversity and climate crises. “Ancestral infrastructure has been deliberately excluded from these conversations. There has been an unlearning of these histories, even though Indigenous People have created the oldest man-made structures on Earth.”

A young fisherman walks under a living root bridge at Mawlynnong village, India. In the relentless damp of Meghalaya’s jungles the Khasi people have used the trainable roots of rubber trees to grow Jingkieng Dieng Jri living root bridges over rivers for centuries. / © Amos Chapple, courtesy of Julia Watson

Books are just one way she advocates for the inclusion of Indigenous design knowledge. The Lo-TEK Institute also offers a Living Earth curriculum for high-school and college level students, featuring 10 Indigenous, nature-based innovations.

And she’s working with firms like Buro Happold to “co-create hybrid technologies of the future” and with attorneys like Comar Molle to protect the intellectual property of Indigenous Peoples. “We can co-create infrastructure with Indigenous knowledge,” protecting their intellectual property at the same time.

Symbiocene exhibition / Dezeen, courtesy of Julia Watson
Symbiocene exhibition / Tim P. Whitby, courtesy of Julia Watson

Watson used her keynote to announce a historic call to action with ASLA and Indigenous partners: Co-create a future that heals land and culture. The call to action was developed by Watson, Johnston, the Indigenous Society of Architecture, Planning, and Design (ISAPD), and ASLA and its Biodiversity and Climate Action Committee. It outlines three key strategies:

  • Respect Indigenous Knowledge
  • Empower Future Generations
  • Help build an Indigenous landscape architects’ network of ASLA members and work in collaboration with groups like ISAPD

During a follow-up conversation with Watson and Johnston, José de Jesús Leal, ASLA, Principal and Director, Native Nation Building Studio, MIG, and member of the ASLA Biodiversity and Climate Action Committee, kicked-off the discussion by asking: “Can Indigenous knowledge outpace our current problems?”

Paul Fragua, a Tribal Elder and architect at MIG, said that while landscape architects and ASLA are celebrating 125 years of American practice this year, Indigenous Peoples have 3,000 years of experience stewarding landscapes. “We need to get started on the next 3,000 years. There is an urgency not for me, but for future generations.”

Johnston sees the landback movement, which has grown in the past five years, as a key way to address our current challenges.

While Native communities are buying land themselves, it’s usually less than 100 acres at a time. “The U.S. government, churches, and private landowners in the U.S. have hundreds of thousands of acres that could be returned to Native stewardship.”

In a few instances, public parks are now being co-managed by the National Park Service and Native Nations. “Having Native Americans in positions of leadership in the Department of Interior and National Park Service enabled that,” she said.

“There are two barriers — getting land back plus a lack of resources,” Leal said. “Native Nations have to be able to take care of the land they get back. It’s not just the actual property, but deep collaboration with the land.”

One approach may help increase resources. In the San Francisco Bay Area, there’s a voluntary land tax people can pay to support local tribal communities. “You can pay it whether you rent or own,” Johnston explained. The funds enable Native communities to buy back more land. Johnston wants to see more of those kinds of funds go directly to grassroots Native community leaders and non-profits that are “revitalizing land and culture.”

To outpace our problems, Watson thinks the “software” that runs our societies needs to change. “A value system is a compass of how to live. These value systems are rooted in a cultural worldview.”

In New Zealand, the Maori have a “software that guides how they take care of the land.” That software shapes their language, which is place based. In effect, their beliefs and worldview and how they communicate are tied to places. “So when we design systems in these places, we need to build the cultural framework of the communities. The belief system is the core.”

Fragua noted that in New Mexico, Pueblo peoples view some mountain peaks as sacred. They are places that transcend this world and connect us to the spiritual world. That is another example of a belief system rooted to a place.

Shiprock, Diné (Navajo) Nation, New Mexico / Wikipedia, Bowie Snodgrass, CC BY 2.0

Landscape architects asked the group questions about how to implement these ideas in contemporary projects.

Johnston and Watson said it’s important to hire Indigenous designers. And Leal added that it’s important to set those relationships in truth. “We need to start fresh relationships and beat stereotypes.” When reaching out to Indigenous designers and communities, “reach out and ask for their voice, but respectfully.”

They also noted that Indigenous design doesn’t necessarily mean creating room for nature at the expense of people. “Indigenous people designed some of the most densely populated cities in South America,” Johnston said. And it’s also not about rewilding landscapes. “American landscapes were never wild to begin with. They were always managed.”

Non-Indigenous designers can also work to “interrupt the harm,” Watson said. “You can document what has been erased and ensure Indigenous landscapes aren’t forgotten.”

Fragua said that many Indigenous communities follow the “great law of peace because there has been so much war. Resilience comes now from resistance [against inequality]. The creator wants us to live as equals.”

And for too long, there has been a separation between people and nature. “We need an integrated approach, a unity where we are part of the world,” Johnston said. Communities need to return to an ancient Indigenous philosophy: “We live in Earth and are born of the Earth. Landscape is a part of ourselves.”

“Culture is living and can change.”

Landscape Architecture Solutions to Climate Change Generate Significant Economic Benefits

Thornton Creek Water Quality Channel, Seattle, Washington / MIG

ASLA Fund releases new research on the economic benefits of nature-based solutions

The American Society of Landscape Architects (ASLA) Fund, a 501(c)(3) organization, has released a new brief on the economic benefits of landscape architecture and nature-based solutions.

The brief is developed for global and U.S. economic policymakers meeting at the UN Framework Convention on Climate Change (UNFCCC) COP29 in Baku, Azerbaijan. ASLA is an official observer of the COP process, and its representatives have attended COPs for the past three years. Pamela Conrad, ASLA, PLA, Founder, Climate Positive Design, is ASLA’s delegate this year.

Dr. Jennifer Egan, PhD, program manager, University of Maryland Environmental Finance Center (EFC) in the School of Architecture, Planning, and Preservation developed the summary and economic benefit estimates. The EFC received a grant from the ASLA Fund to develop these analyses, which summarize findings from research literature, national and international reports, and 175 case studies.

The brief finds that landscape architects increase economic value through their approach to planning and designing nature-based solutions.

Their work on nature-based solutions creates economic benefits in five key areas:

  • Improved Human Health and Livability
  • Expanded Investment and Sustainable Jobs
  • Increased Biodiversity
  • Going Beyond Net-Zero
  • Strengthened Resilience

The Environmental Finance Center created the brief and a supplementary analysis:

Landscape Architecture: Maximizing the Economic Benefits of Nature-based Solutions Through Design: A 10-page brief that summarizes estimates of economic benefits for global and U.S. policymakers.

An Analysis of Benefit Values: 175 Landscape Architecture Case Studies in the U.S.: A 12-page supplementary analysis for economic and landscape architecture researchers and educators that explores economic benefits found in the Landscape Architecture Foundation (LAF)’s Landscape Performance Series Case Study Briefs.

“We listened to global policymakers last year at COP28 in Dubai. They seek to scale up investment in nature-based solutions but need to know how much these solutions cost and their economic benefits,” said ASLA CEO Torey Carter-Conneen, Hon. ASLA.

“We now have some solid numbers that show landscape architects generate significant economic value through the way they design these solutions. But we’ll also start an ambitious research agenda to calculate the economic benefits we currently can’t measure.”

Dutch Kills Green, Queens, New York (before). WRT and Margie Ruddick Landscape / WRT
Dutch Kills Green, Queens, New York (before). WRT and Margie Ruddick Landscape / WRT

Highlights include:

  • Nature-based solutions such as rain gardens, bioswales, and green roofs effectively manage stormwater. These features can be constructed for 5-30 percent less and maintained for 25 percent less than conventional gray infrastructure.
  • Every dollar invested in ecosystem restoration returns $5 to $28 in benefits, depending on the ecosystem.
  • Urban trees provide approximately $88 billion (US$ 2024) in carbon sequestration annually.
  • Every dollar invested in parks and green space can generate between $4 and $11, due to increased tourism, improved property values, and enhanced community health.

ASLA’s Climate Action Plan identified the need for this economic benefits work.

At COP29, Landscape Architects Will Workshop Landscape Solutions to Climate Change with World Leaders

Pamela Conrad, ASLA / Climate Positive Design (left); Kotchakorn Voraakhom, International ASLA / Landprocess (right)

Delegates will highlight the key role of landscape architecture strategies in maximizing the benefits of nature for people and communities

ASLA will be represented by two delegates at COP29 in Baku, Azerbaijan. This is the third year ASLA has been an NGO observer to the UN Framework Convention on Climate Change (UNFCCC) Conference of Parties (COP) process.

ASLA’s delegate:

And the landscape architect delegate of the Government of Thailand:

At COP29, Conrad and Voraakhom will host Working with Nature: Landscape Action in National Adaptation Plans, a workshop for global policymakers in the blue zone, the delegate area of the conference. The event is organized by the UNFCCC, Climate Positive Design, ASLA, Landprocess, and IFLA. Location, date, and time: Blue Zone, Thailand Pavilion, November 18, 2-4 PM, Azerbaijan.

“Every member nation of the UN has committed to creating National Adaptation Plans by 2025. These plans can either continue business-as-usual – or advance smart nature-based solutions. Pamela and Kotch will show policymakers how to design with nature, so communities can adapt to climate impacts but also reduce emissions and restore ecosystems at the same time. It’s the start of such important global work,” said ASLA CEO Torey Carter-Conneen, Hon. ASLA.

“This is the first major blue zone workshop on landscape solutions hosted by the UN and guided by landscape architects. We’re excited to lead an event where notable country leaders and technical experts will present success stories and lessons learned throughout the world. Together, we will explore pathways to scaling up nature-based solutions,” Conrad said.

At the event, Conrad will introduce WORKS with NATURE, a new guide being developed by Climate Positive Design in collaboration with Landprocess. The guide has been spearheaded by Conrad as part of her two-year ASLA Biodiversity and Climate Action Fellowship.

The guide highlights 100 low-carbon nature-based techniques that help communities adapt to extreme heat, flooding, wildfire, and drought while supporting health and biodiversity.

Half of the techniques are found in developing countries and half in developed countries, with 38 countries represented. There is also an even mix of rural and urban techniques.

ASLA 2019 Professional General Design Honor Award. Chulalongkorn University Centenary Park. Bangkok, Thailand / LANDPROCESS, Suratchana Pakavaleetorn

Landscape architecture delegates will also present at these blue zone sessions:

Rethinking Our Cities: Leveraging Urban Planning and Design Solutions for Sustainable Buildings, Neighborhoods, and Lifestyles
Location, date, and time: Buildings and Cooling Pavilion, Blue Zone, International Code Council (ICC) Pavilion, Number G10, 20 November 20, 5-6 PM, Azerbaijan
Organizers: UN-Habitat, Laudes Foundation, ASLA, IFLA, Climate Positive Design, Architecture 2030, and Harvard University Graduate School of Design

Strategic Foresight in Support of Visioning for Future Resilience
Location, date, and time: Blue Zone, November 20, 1:45-3:45 PM, Azerbaijan
Organizers: UNFCCC, IFLA

Pathways to Nature-Positive Solutions: Integrating Nature-Based Solutions into Urban Infrastructure Design
Location, date, and time: Buildings and Cooling Pavilion, Blue Zone, November 21, 4-5.30 PM, Azerbaijan
Organizer: UN Habitat, IFLA

Nature Positive Cities: Pathway to Urban Adaptation and Transformation
Location, date, and time: Thailand Pavilion, Blue Zone, November 14, 11 AM-12 PM, Azerbaijan
Organizers: UN Habitat, World bank, Bangkok Metropolitan Administration, Japan International Cooperation Agency, United Nation University, IFLA

“Key topics include integrating green infrastructure, restoring biodiversity, and using nature-based solutions for flood management and air quality improvement. Experts will discuss the role of financial tools, which provide funding for climate resilience projects and support urban areas in recovering from climate-related disasters. This comprehensive approach prioritizes ecological health and urban livability, offering adaptable frameworks for building climate-resilient cities.”

Building Inclusive and Resilient Communities: From Net Zero Campuses to Sustainable Urban Development
Location, date, and time: Thailand Pavilion, Blue Zone, November 16, 10-11 AM, Azerbaijan
Organizer: National Higher Education, Science Research, and Innovation Policy Council (NXPO), United Nation University, IFLA

“This discussion will explore innovative strategies for fostering sustainable and inclusive communities through diverse lenses of development. NXPO will share insights on creating Net-Zero campuses as models for sustainable education and research spaces that drive climate action.”

Nature-Inspired Design for Resilience: Redefining Sustainability in Climate Action
Location, date, and time: Thailand Pavilion, Blue Zone, November 16, 2-3 PM, Azerbaijan
Organizers: IFLA, Dersyn Studio, Chulalongkorn University, United Nation University

“This session focuses on the role of architecture in advancing climate resilience, focusing on sustainable design, adaptive building materials, and energy-efficient systems. It will showcase strategies for creating climate-responsive structures that reduce emissions, manage resources sustainably, and integrate seamlessly with local environments. These strategies promote resilience and adaptation in urban spaces.”

Harmonizing Futures: Bridging the Digital Divide with AI and Indigenous Knowledge for Climate Action and a More Inclusive and Sustainable World
Location, date, and time: Thailand Pavilion, Blue Zone, 1-2 PM, Azerbaijan
Organizers: United Nation University, Intergovernmental Panel on Climate Change, Center of Excellence in Indigenous Knowledge Systems, University of KwaZulu-Natal, South Africa, Institute for Environment and Human Security, United Nations Economic Commission for Africa, IFLA

“This high-level dialogue addresses the urgent intersection of climate change and human health, focusing on how environmental shifts impact public health and healthcare resilience. Experts and policymakers will discuss strategies to bridge climate and health policies, explore adaptive healthcare infrastructure, and assess risks posed by climate-induced diseases.”

Urban Climate and Human Health: Building Resilience for Thriving Cities
Location, date, and time: Thailand Pavilion, Blue Zone, November 20, 10-11 AM, Azerbaijan
Organizers: The Cultural Landscape Foundation, Monash University, IFLA, and National Health Institute

“This session explores how resilient infrastructure, green spaces, and sustainable policies can mitigate health risks posed by climate change. Experts will discuss strategies for reducing heat, improving air quality, and creating healthier urban environments, emphasizing the importance of climate-responsive planning to support thriving, resilient communities.”

Yerba Buena Island, San Francisco, California / CMG Landscape Architecture

At COP29, our member leaders will explain how landscape architects design nature-based solutions that create real benefits for people and communities:

1) Increased Biodiversity
Nature-positive landscapes are the foundation of terrestrial ecosystems and efforts to achieve the goals of protecting 30 percent of ecosystems by 2030 (30 x 2030) and 10% net biodiversity, restoring global ecosystems, and increasing and protecting biodiversity.

2) Improved Human Health and Livability
Accessible public landscapes, such as parks and recreation areas, provide proven physical and mental health benefits that reduce healthcare costs and increase community cohesion.

3) Going Beyond Net-Zero
Landscapes are the most efficient way to store carbon and achieve zero embodied and operational emissions and double carbon sequestration by 2040.

4) Strengthened Resilience
Healthy, biodiverse landscapes that store carbon in trees, plants, and soils also increase people’s resilience to climate impacts, such as extreme heat, flooding, drought, and sea level rise.

5) Expanded Investment and Sustainable Livelihoods
When woven into communities, nature-based solutions become resilient assets that lead to increased investment in housing, infrastructure, and public amenities, and create sustainable local livelihoods.

De-Pave Park, Alameda, California / CMG Landscape Architecture