The three-year process of installing a rain garden at Thrasher Elementary is finally complete.
Signal Mountain-based TenneSEA (Student Environmental Alliance) received a $90,000 grant from the Department of Agriculture to develop an Education into Action program to reduce non-point-source pollution in the area. Through the grant, rain gardens were established at Thrasher as well as Red Bank High School and Scenic Land School.
“The purpose of a rain garden is to filter and clean up stormwater so pollutants don’t go into the streams, and it also provides a great habitat and learning station on campus,” said Mary Beth Sutton, a Signal resident and director of TenneSEA.
She said too much of the land around Thrasher has been paved, which prevents stormwater runoff from getting cleaned by going through the soil and tree roots. Normally, water would be recharged by passing through the water table before running into streams, she explained.
“If it flows too fast, the stormwater goes straight into streams and rivers full of all sorts of pollutants,” said Sutton.
STEM teacher and Thrasher Environmental Club faculty sponsor Heidi Mies taught her students about stormwater and the benefits of a rain garden and how it works, and the students came up with rain garden designs that they presented to principal Regina Brock.
They used fluorescent dye to determine the course stormwater was taking in the Thrasher parking lot and created a planted depression where the runoff was draining. Paul Thomas of Stantec explained the engineering aspects of the project to the students and helped with the garden’s installation.
Students voted on components of their designs that they wanted included in the rain garden. They incorporated meditation rocks as well as native plants that, in addition to absorbing runoff and pollutants, also attract butterflies and songbirds.
“It was good to get the kids to realize they have to work together to solve problems,” said Sutton.
Types of plants used include flowers to attract butterflies, such as azaleas, black-eyed Susans, irises and daylilies, as well as cardinal flowers, rushes, cattails, tulip poplars and river birches.
“It’s neat to have lots of different habitats in the same space,” Sutton said.
Mies said she plans to use the rain garden for all types of STEM activities, from tracking the types of animals the garden attracts to figuring out the volume of water that flows through the system.
Since the garden is filled with native plants, it is relatively low maintenance, said Sutton.