Two bioswales that were installed by Huron Pines and its municipal partners in Au Gres were planted with native wildflowers by students at Au Gres-Sims High School May 27. These specialized rain gardens, one on school grounds and another near Kinder Platz Park, are designed to capture, hold and filter stormwater runoff before it reaches the Au Gres River and Lake Huron.
Stormwater carries pollutants like road salt, bacteria, sediment and motor oils from roads and other hardened surfaces. Once they enter rivers and lakes, these contaminants can result in beach closures and degraded fish and wildlife habitat, all of which impacts recreation, tourism and the environmental health of a community.
Bioswales channel stormwater from the surrounding landscape and use a combination of soil, gravel and deep-rooted plants to filter the runoff before it reaches nearby waters. Two similar bioswales were installed at Au Gres Riverside Park in September 2020.
As a Lake Huron Forever community, Au Gres is prioritizing the reduction of stormwater runoff from within the city limits by retrofitting existing infrastructure and incorporating nature-based solutions, sometimes referred to as green infrastructure. In January, Au Gres became the first community to take the Lake Huron Forever pledge, committing to the protection of the water quality of Lake Huron by improving the ways it manages stormwater while also inspiring its citizens to action.
The project involved excavating a 150-foot trench along the sidewalk on Court Avenue at the school, and another shorter trench at Kinder Platz playground on Michigan Avenue. These were then backfilled with layers of gravel and soil to allow for the retention and drainage of stormwater, then planted with native wildflowers and grasses by environmental science students at Au Gres-Sims High School. Underground pipes were installed to divert stormwater from the streets into the bioswales.
Michigan Avenue was identified as a high-priority area in a stormwater assessment that Huron Pines completed in 2020. Assessments look at maps of existing infrastructure like storm drains and outlets, combined with precipitation modeling, to estimate stormwater volumes across different parts of a city.
Students of Luke Freeman’s environmental science class helped design the bioswales and grew many of the native plants. Students collected seeds from the rain gardens at their school and Riverside Park last year and grew them in the school’s heated greenhouse. Many of the plants are species which are beneficial to pollinators like bees, birds and butterflies.
The project is funded in part by Saginaw Bay Watershed Initiative Network, Bay Area Community Foundation and National Fish and Wildlife Foundation Sustain Our Great Lakes program.
See photos from the planting day below.