Environmental science students find restoration project in Norwich’s back yard© Sept. 10, 2010, Norwich University Office of Communications
The Dog River, which flows through Norwich University’s Northfield, Vt., campus, is shifting and changing, causing no shortage of problems for the college and the town.
Norwich stands to lose a rugby pitch and a soccer field due to natural erosion and movement of the stream bed. The vegetation along the buffer zone—35 to 50 feet on both sides of the river—is inadequate, which leads to faster erosion. To add to the difficulties, banks of the river are choked with Japanese knot weed, an invasive species that prevents the growth of more beneficial plants. This has led to a decline in the fish population due to loss of habitat. In fact, fishing along the Dog has been limited to catch-and-release in recent years.
It’s exciting that, this early in your life someone might actually use your ideas to help save a river.
~ Chris Barber,
environmental science student
The Dog River needs some intervention, but controlling the natural path of a river is a difficult task. Water tends to go where it wants to go.
“It will always win,” said Richard Dunn, a Norwich geology and environmental science professor. “Always.”
Fortunately, the Northfield Conservation Commission and Norwich, the country’s oldest private military college, have formed a partnership that is paying off in a variety of ways. Students are taking the lead in determining how to stabilize the river’s natural erosion with fewer side effects, and putting the plan into action.
“We’re trying to use new, green techniques instead of the old riprap, which actually speeds up the erosion,” said Chris Barber, an environmental science major who spent his summer working with Dunn to map the 3.2-acre section of the river corridor that lies on Norwich property.
The riprap he refers to is part of a common method of protecting banks with heavy rubble and boulders, and known to cause unintended speeding of erosion in other sections of the river. Barber surveyed the river and its banks and used an AutoCAD drafting program to create a minutely detailed picture of the Dog, which included a cross-sectional profile showing the depth of pools and height of banks. In addition, he determined the areas of highest erosion capacity, and worked out a plan to slow and channel water in ways that will hopefully stop, or at least decelerate, the process. The river is changing very fast, he said.
“If you saw this river just four years ago, it looked very different,” said Barber, who minored in environmental engineering.
After weeks scrambling through dense underbrush and pools of water, he began work on a report. Barber’s recommendations included techniques such as burying the trunks of willow trees so the root structures rise above the water, creating frameworks that hold earth and allow plants to take root. He also advocates use of tubular “logs” made of rocks, wire and coconut fibers that compress and hold the banks temporarily while plants grow.
Among other ideas for “training” the river, he would like to see Norwich engineering and architecture students redesign a footbridge over the river and change it into a mobile structure, allowing them to pull out the bridge foundation and open up the channel.
Environmental science student Brian Demers approached the problems from a different angle, performing geochemical testing of the soil and vegetation in the river buffers. This helps them determine which plants will best hold the banks in place, according to Dunn, and also starts a database of knowledge about the moisture, carbon levels and acidity of the soil. Students will stay involved with this project, recording how the system evolves over time, he added.
“We’re going to document every year how things are changing,” said Dunn, who has been involved with smaller studies of the corridor since 2004. “We’re going to continue to monitor it.”
The project escalated when Leslie Matthews, a member of the conservation commission, approached Norwich with a plan to have students and faculty study the Norwich land. This came after an assessment of the river from its headwaters to the confluence with the Winooski River. Securing a grant through the state’s Lake Champlain Basin Program, she will work with Norwich to set up a volunteer effort in the spring of 2011. Students and other volunteers will landscape the area, planting trees and shrubs purchased with grant money. Details of the plan will be based on the student recommendations and existing “best practice” habitat restoration procedures.
Matthews also plans to set up educational signs to teach people from the community about restoration efforts. She wants this awareness to spark similar projects.
“There are a lot of people from the community who use that area for recreation, which Norwich generously allows,” said Matthews. “We’re hoping this project serves as an example to other private land owners.”
Although he’s completed his class requirements and will graduate in fall 2010, Barber intends to stay involved with the project and see how his recommendations are implemented.
“It’s exciting that, this early in your life someone might actually use your ideas to help save a river,” he said.