Rain gardens along the Green Line

CGEE Student Voice
Water & Watersheds
by Jenni Abere


On a rainy Friday afternoon, my Environmental Studies class went on a tour of some of the stormwater features along University Ave in Saint Paul. When the Green Line was constructed here five years ago, Capital Region Watershed District took the opportunity to integrate some rainwater best practices. This was possible due to CRWD's regulatory authority; the Green Line route in Minneapolis does not have the same features.

The first feature we learned about is the tree trench system. The Green Line project led to a much greener University Avenue: there are trees on both sides of the street. The bricks around the trees are pervious, allowing rainwater to soak through the cracks instead of running off into the street. The picture above also shows the informative signs that are on display. The sign, titled "Rooting Out Pollution," explains the many benefits of permeable land and plants; less water runoff, cleaner water, and cleaner air.

In this rain garden, water from a nearby parking lot is piped in, and water from the street runs through the decorative grate. The plants here, mostly grasses, are selected specifically for their ability to withstand high levels of pollution. In the time that we stood there, I watched the rain carry some oil from the road along the curb, and into the rain garden. Despite these tough conditions, the plants looked healthy. All things considered, it's better for pollution to end up in a rain garden than directly in the river. CRWD performs regular maintenance on rain gardens.

The above rain garden is located next to a McDonald's. Because of this, there is a fair amount of litter. But the plants and trees are doing very well. It's great to be more aware of rain gardens, because once you notice them, you see them in a lot of places. But after this field trip, every time I see a regular patch of grass I just want to plant a rain garden there.

The good news is, a large rain garden will be planted near Hamline this month! Seeing the nearby rainwater infrastructure made me very excited to participate in this project.