From Ditch to Delight: Movement Gives 'Daylight' to Lost Streams, Improves Water Quality

FAYETTEVILLE, Ark. — As American cities developed, many streams and rivers flowing through them were buried underground, channeled into huge pipes or relegated to concrete ditches in out-of-sight areas. Today, cities across the country have discovered the economic and ecological value of those streams and have begun to return them to a man-made version of their original, natural state.

The process of restoring streams from underground or back alleys is known as “daylighting.” It is slow and arduous work, but a prominent researcher at the University of Arkansas says the effort is worth it. Marty Matlock, associate professor of biological and agricultural engineering with the Arkansas Division of Agriculture, argues that bringing streams to the front of developments and restoring them to a natural state will yield long-term economic benefits for cities and health benefits for the people who inhabit them.

Communities need the ecological services, such as disinfection and processing of nutrients, that streams provide, Matlock said. Natural streams disinfect water and treat nutrients such as nitrogen and phosphorous. Allowing streams to perform these natural functions will decrease the extent to which cities or other local governments will have to treat water artificially, which is an expensive process.

“We’re drinking that stuff or at least someone else is, and if we keep shoving it down a concrete stream, somebody, somewhere has to treat it,” Matlock said. “If we can increase the ecological services upstream and preserve them, it will ultimately reduce costs of treatment and increase confidence in our drinking water. So, it’s not just aesthetics. This is the direction we’ve got to go if we want continued fresh water at reasonable costs.”

Historically, most stream-restoration projects have been done from the perspective of landscape architecture or restoration ecology. As a licensed engineer and registered ecologist, Matlock is one of the few academic researchers nationwide who is qualified to design stream-restoration projects from an engineering perspective. In applying the science of ecology to engineering practice, he and his research team design natural streams that interact with people and function in an urban environment.

“As ecological engineers, we can predict outcomes with a high level of confidence,” Matlock said. “These predictions, which are based on quantifiable data, satisfy the concerns of community leaders, regulatory agencies, property holders and citizens. We’re moving this from pure science to an engineering practice that uses and respects science.”

Matlock and his research group recently completed the first phase of an innovative greenway development in Rogers, Ark. By returning Blossom Branch Creek to its floodplain and restoring ecological services to the creek, the stream system will control flooding, decrease the need to treat nutrients in the stream and provide a recreation venue for community residents. UA researchers conducted analyses of the ecological services, hydrology and geomorphology of the creek. They then worked with the city of Rogers to design a greenway park, including a recreational trail. The researchers also supervised construction of the project.

Stream restoration activities included decreasing the topographical slope of the stream and creating pools, runs and riffles, or shoals, based on engineers’ designs. Part of this involved converting a straight channel into a sinuous stream. The researchers also stabilized stream banks by planting trees and reconnected the stream’s channel to the flood plain to give water a place to go during floods. Throughout the construction process, researchers hosted technology-transfer workshops at the site to train developers, city planners and engineers on more sensitive drainage practices.

In a similar project, Matlock and his research team conducted ecological, geomorphological and hydrological assessments of a stream near downtown Warren, Ark. The polluted creek frequently floods, causing a public health and safety problem. As they did with the Rogers project, researchers created a design for stream restoration that includes riffle-pool-glide flow structures, landscaping plants for bank stabilization and a plan to return the stream to a more natural, sinuous flow. The last feature, combined with restoration of the stream’s floodplain, will address the flooding problem.

For this project, Matlock’s research team collaborated with the UA School of Architecture’s Community Design Center (UACDC) and members of a city committee to develop an urban greenway along the creek. Earlier this year, the UACDC won a prestigious American Institute of Architects Honor Award for its greenway design.

Matlock’s group has also received a $135,000 grant from the city of Fayetteville to identify and evaluate streams that need to be restored.

Matlock coordinates the UA Ecological Engineering Group (EEG), a concentration of researchers who combine the science of ecology with the process of engineering to solve complex ecological problems. Ecological engineering is a new but rapidly growing discipline. It is emerging from the integration of many areas of practice, including ecosystem management, restoration ecology, ecosystem modeling, and urban planning.

Ecological engineers at the University of Arkansas use these skills to solve problems in source pollution control, watershed management, urban stream restoration, greenways design, and water quality management. The EEG is at the forefront of developing this new discipline. In fact, the University of Arkansas hosted the fourth annual meeting of the Ecological Engineering Society of America in 2004. There are fewer than 20 ecological engineering programs nationwide.

The EEG consists of faculty members from the Department of Biological and Agricultural Engineering, who collaborate with faculty from the UA departments of Civil Engineering, Chemical Engineering, Geosciences and Agricultural Economics. EEG also works with researchers in the Sam M. Walton College of Business and local representatives of the U. S. Department of Agriculture-Agricultural Research Service, the U. S. Geological Survey, the U.S. Army Corps of Engineers, the Nature Conservancy, the Audubon Society, and municipal and state governments.