Water Ways – Researchers Dream of Sculpting Streams
Steve Luoni points to side-by-side photographs, a juxtaposition of images that illustrates — better than 1,000 words can explain — how engineers, developers and urban planners have failed with water. The pictures document the same scene, but the images are very different. On the left is a small creek dominated by a wide, concrete sidewalk. On the right, the sidewalk has disappeared and the creek dominates everything.
Ripples on the surface illustrate the stream’s violent surge. The bank is gone, and the water is poised to invade a large, flat lawn where children normally play safely. It’s no surprise that people are conspicuously absent.
The volume of water in such a confined space is hard to fathom. It looks like someone’s trying to pour a gallon of chocolate milk into a shot glass. The image is disturbing because the bloated creek is completely out of control. There’s a kind of anarchy to it. You sense the water could do anything, go anywhere, in the blink of an eye.
“My guys have taken pictures in dangerous places,” said Luoni. “They aren’t easily scared, but they said they were pretty anxious when they took those shots. And that was just ten minutes into a typical storm.”
The photograph captures the awesome power of hydrology and the dangerous consequence of burying creeks underground, turning them into concrete ditches or otherwise destroying their natural structure. In this case, the creek is College Branch, a first-order stream — which means it has no tributaries — buried under Donald W. Reynolds Razorback Stadium, Bud Walton Arena, a large parking lot and other structures on the western edge of the University of Arkansas campus.
The stream is the focus of an innovative community design project inspired by collaboration between Luoni’s center, which includes students from the School of Architecture as well as permanent project designers from the center, and a group of ecological engineers led by Marty Matlock, associate professor of biological and agricultural engineering. Matlock’s group consists of faculty, students and research engineers who also work closely with faculty in other UA schools and colleges.
In addition to the College Branch project, officially called Campus Hydroscapes, Luoni and Matlock have reached beyond the UA campus and Fayetteville to help an Arkansas town begin the arduous process of turning a polluted, flood-prone creek into an ecologically healthy stream that will serve as the core of an urban greenway and park. Another project, an innovative Habitat for Humanity housing development in Rogers, will be the first totally “green” neighborhood in Arkansas and possibly the Midwest. With hydrological analysis by the ecological engineering group, landscape design by Mark Boyer, associate professor of landscape architecture, and community and building design by staff and students at the design center, the Habitat development will reduce stress on municipal services by absorbing and treating storm-water runoff on site. Design of the Habitat development will also promote environmental responsibility and a deeper sense of community among residents.
buried pipes and concrete ditches: the legacy of ‘command and control’
Sadly, College Branch is the rule rather than the exception. Urban streams in virtually every American city suffer from the effects of conventional civil engineering — what a new breed of urban planners call “command-and-control” design. Chronic and flash flooding due to the elimination of flood plains and wetlands, stream-bank erosion that encroaches on and threatens property, sediment migration, loss of wildlife habitat and inferior water quality are all consequences of relegating streams to underground pipes or paved culverts.
Luoni and Matlock say these and other problems exist because planners, developers and engineers do not understand the relationship between hydrology and the value of essential ecological services provided by streams. Command-and-control strategies are ineffective in some contexts because they do not respond to environmental change. They’re inflexible; they lack the ability to adapt or self-correct. This static nature complicates environmental problems and makes them more expensive to correct. The result is that cities and counties have been forced to spend taxpayers’ dollars on more infrastructure and services to correct problems that could have been better addressed in the beginning.
“If we keep shoving water down a concrete ditch, somebody, somewhere has to treat it,” Matlock says. “If we can increase the ecological services upstream and preserve them, it will ultimately reduce costs of treatment and increase public confidence in water quality.”
Like the human body, the earth is a dynamic system with awesome power to regenerate and heal. Of course, humans have exerted their influence on the environment and severely limited the earth’s propensity to self-correct. Almost daily, we see how man-made inventions threaten the earth’s ability to achieve what Matlock calls dynamic equilibrium. Water is an integral part of the regenerative and healing process. If streams can exist in something close to a natural state, they will help the earth absorb, disinfect and treat nutrients, such as nitrogen and phosphorous, and toxic compounds, such as pesticides and cleaning products. This is what Matlock means by “services.”
“Ecological services are the key,” he says. “It’s not ecosystem function or ecosystem process. It’s service. It’s the things we get from the ecosystem that we value.”
These services include food, fiber and other raw materials, aesthetics and recreation. However, the mundane but probably more valuable services are waste treatment, disinfection, nutrient cycling and carbon sequestration in trees.
Allowing water and streams to perform these natural functions will decrease the extent to which cities and other local governments will have to treat water artificially, which is an expensive process. Matlock and Luoni argue that developers, planners and engineers have either ignored or failed to consider these important ecological services and their long-term benefits.
“These services are hugely valuable on a per-unit-area and per-unit-volume of soil,” says Matlock. “We don’t think about these things at all when we pave over rich, loamy earth to put in a Wal-Mart or housing addition. When this happens, we don’t consider the fact that we’ve just encapsulated so many thousand cubic meters of living soil forever.”
stream restoration, urban greenways and low-impact development
Matlock and his team put streams back together, make them into something that closely resembles what they were before humans mangled them. Property owners, developers, government officials and environmentalists ask Matlock to share best practices for developing property around a stream.
It sounds weird that someone would design a stream, but that’s exactly what members of the ecological engineering group do. They use the science of ecology to design and build natural streams that not only process pollutants and control flooding but also interact with people by providing recreational space or something pleasing to look at. In essence, Matlock’s group converts lifeless, artificial conveyances into dynamic, robust and diverse ecosystems that respond and adapt to environmental change.
How do they do this? The process begins with a fundamental understanding of hydrology, stream geomorphology and wildlife habitat. After assessments of the aquatic and terrestrial environment, the researchers develop a plan that may include some or all of these strategies: decreasing the topographical slope of the stream; restoring the stream’s basic structure by creating a series of pools, runs and riffles, or shoals; converting a straight channel into sinuous stream; reconnecting the winding channel to the flood plain; and stabilizing stream banks by planting trees and other native plants.
As Matlock says, the priority of every engineering project is to ensure the safety of people and property. Design to maximize risk reduction. Because water has such a powerful effect on the environment and can threaten the safety of people and property if the natural systems that convey it are abused, sound hydrological design is the foundation of the collaboration between Matlock’s engineers and Luoni’s designers. They agree that hydrology is the base of everything else.
“First, we take care of the stream,” Luoni says, “and then we take care of the urban systems around it. Improvement of ecological services in the stream serves as a platform for community development.”
Beyond hydrological design, the line separating engineering and community design often blurs. While Matlock’s engineers create a plan to return a stream to its floodplain, Luoni’s planners visualize and design human spaces within the floodplain. Discussion between the two groups ensures that designers consider ecological services as part of a community development plan. Although areas of expertise overlap, Luoni’s shop generally takes over at that fuzzy place where people can begin to occupy outdoor space without damaging the stream.
The result of this discussion is Campus Hydroscapes, which includes three design concepts for the remediation of College Branch as well as campus improvements on both sides of the stream, and Riparian Meadows, Mounds, and Rooms: Urban Greenway for Warren, Arkansas, a study and design model for an approximately half-mile-long public greenway along a polluted and flood-prone creek that runs through heart of Warren, Ark. In addition to the plan for stream restoration, Riparian includes a series of outdoor rooms, a landscaped walking loop and raised mounds for performances, picnics and plays. As part of a broader plan for development, the study suggests refurbishing existing buildings and converting them into valuable space for public events.
The Warren project generated notoriety for the design center in 2005. In January, the center won an American Institute of Architects Honor Award for Outstanding Regional and Urban Design. The AIA honor awards constitute the highest recognition in the nation for design accomplishment in architecture, interior design and urban planning. The award is the first national AIA recognition for an Arkansas project since the late architect Fay Jones was designing homes and chapels in his native state. The design also won an Honor Award from the Arkansas Chapter of the AIA.
In September, the Holcim Foundation for Sustainable Development, an organization that has developed a worldwide forum on design and sustainability, awarded $10,000 to the center for its work on the Warren Project. Luoni is particularly proud of the Holcim award in light of the center’s emphasis on sustainable design and its collaboration with Matlock’s group.
“In the architecture profession, sustainability and good design have been seen as antithetical for last 50 years,” he says.
Although it is located in an upland area and not focused on a specific stream, the current collaborative project will benefit water quality downstream by processing nutrients and pollutants onsite. This summer, the Benton County, Ark., chapter of Habitat for Humanity will begin construction on Habitat Trails, a radically different kind of residential development.. Staff members and students at the design center created a neighborhood model with architectural and landscape-design features that promote community and encourage social exchange among residents. The homes — 17 units in 14 structures — will face each other and a large, open green space. As part of a Habitat project, the homes will be affordable and not too big; each unit will be approximately 1,100 square feet.
Without compromising architectural aesthetics, the structures will be simple and flexible in terms of multiple uses for indoor and outdoor spaces. Carports, which may be used to park a car in or create an outdoor or indoor room, will be at the back or recessed on the side of the homes. Welcoming neighbors, open porches will face the street and common area.
When talking about the development, Luoni uses the word “neighborhood” or “community,” not subdivision. “Subdivision is a real-estate phenomenon,” he says. “A neighborhood is a social, civic and cultural phenomenon.”
If things go according to plan, the development will also be a mini water-treatment plant. The streets will not have expensive catchment infrastructure to convey storm water off the property. There will be no buried pipes or culverts, no curbs and no storm-water drains or inlets. Rainwater and its accompanying pollutants will be retained onsite and percolate into the soil via a series of infiltration systems called bioswales. The runoff will be treated by natural bacteria in the soil via a wet meadow at one end of the development.
Matlock said the site will handle 100-year-flood volumes of water and will also meet the pre-construction, even pre-development conditions. In other words, hydrological design of the development and the plants used in the bioswales and wet meadow will ensure that the five-acre site will hold more water than it did before humans came anywhere near Northwest Arkansas.
“That means remediation is happening,” he says. “We’re not just treating the problem we created, we’re remediating other people’s problems. It shows the power of these ecology-based systems.”
ecology, oikos and the re-convergence of divergent disciplines
Matlock, Luoni and Boyer, the landscape architecture professor, agree that planners’ and engineers’ poor understanding of the connection between hydrology and the ecological services streams provide is indicative of a deeper problem: Humans don’t understand their relationship with the environment in which they live. Nowhere is this more evident than in the things we build. Roads are under water, buildings are crumbling, homes are on fire or falling off mountains and entire cities are sinking into the earth because man builds anywhere and everywhere without respect for or even fundamental understanding of ecology.
Luoni reminds us that ecology is more than a word tossed around by biology professors and environmentalists. He points to Frederic Migayrou, an influential French architect and philosopher, for a deeper understanding. Migayrou traces the etymology of ecology to the Greek “oikos,” which means habitat. In Migayrou’s view, ecologyis a dynamic system, a dialogue between man and nature. It is the place we live, our home. Luoni says this deeper understanding of ecology explains and strengthens the convergence of his and Matlock’s disciplines.
“I think the thing that binds us is the notion of ecology. … If the examination of all habitat, including human habitat, suggests that you look at everything as a resource, then there is no boundary between nature and what we construct as habitat. For me, that’s always been a very important definition that binds our disciplines.”
Luoni says this meaning of habitat and ecology challenges engineers and urban planners to figure out what is fundamentally ecological about environments dominated by humans. A basic principle of ecology, says Matlock, is that pristine or static ecosystems do not exist. Movement and change are constant.
“In ecology, nothing is natural,” he says. “There is no such thing a pristine state, an ideal or undisturbed system. Everything is in the process of changing. There’s one fundamental concept in ecology and ecosystems, and that’s change. So we have to understand that and live within those constraints.”
So far, planners, engineers and developers haven’t done a very good job of designing and building within these constraints. Too many public spaces are planned and built as if rain were not supposed to fall and trees were not supposed to grow. Even more absurd, design of many structures seems to assume that people will not inhabit the structures. Once designers and engineers understand the fundamental concept that everything is in the process of changing, then they can begin to design systems that are robust enough to adapt to changes of the landscape.
Luoni and Matlock agree that one of the big challenges for their disciplines is how to design in human-dominated ecosystems. For this to happen, it is essential that designers and engineers examine ecology. It’s not living in harmony with nature; it’s living in dynamic equilibrium.
“We need to study human-dominated ecosystems as they are, not as we wish they were,” Matlock says. “It’s about adaptation, interaction and dynamic systems.
We are part of that system, but not the sole part. We have to make where we are livable.”
For Matlock, the beauty of his group’s collaboration with the design center lies somewhere in his effort to rediscover the art of engineering and re-converge divergent disciplines.
“Two hundred years ago, the planners of Washington, D.C., New York and Boston got all this,” he says. “Our disciplines diverged, so we’re rediscovering what we already knew. Our collaboration has been incredibly robust and successful because we see the same opportunities before us with the landscape and we have different tools in which to approach those opportunities. The skills are so complementary that after working with them, I don’t see how I could do my job without working with them. Sometimes there are collaborations of convenience; this is now one of necessity.”
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Steve Luoni is director of the University of Arkansas Community Design Center.
Marty Matlock is an associate professor of biological and agricultural engineering in the Dale Bumpers College of Agricultural, Food and Life Sciences, the Division of Agriculture and the College of Engineering.
Mark Boyer is an associate professor of landscape architecture in the School of Architecture.