While fairly common with homeowners, rain gardens are typically not public projects. But that is about to change in 2023. The Minnesota Department of Transportation is exploring budget-friendly green stormwater infrastructures across the state. Two cities have been selected to pilot the program; rural Bemidji and urban Columbia Heights.
Rain gardens collect water from impervious surfaces such as roads and sidewalks. The collected water soaks into the soil, which helps remove harmful pollutants and allows them to break down naturally. This keeps those pollutants out of our lakes and rivers, and reduces the stress on our existing storm drain infrastructure.
MnDOT is interested in rain gardens as a simple, low-cost way to mitigate storm water without the need for underground pipes, major construction, or long project timelines.
Columbia Heights is a prime candidate for a rain garden project for two reasons:
- MnDOT is already planning to conduct a pedestrian safety project on Central Avenue in 2023.
- MnDOT recognizes HeightsNEXT as the leading volunteer organization that cleans Central Avenue twice per year.
Specifically, a 600 square foot area on the southeast corner of Central and 49th Avenues is being considered for the rain garden project near the pedestrian foot bridge. Site selection and a feasibility analysis are underway, including soil tests. Layout and planning are set to take place this spring, which will include the marking of nearby utilities. Various types of native plants and grasses are still being considered. Any successful rain garden will need to contend with extreme weather conditions, road salt, and other long-term factors.
During construction, MnDOT will implement a traffic control plan that may include a lane closure on Central Avenue. This is to ensure safety of the crew and any volunteers that are welcome to help with the construction of the rain garden. Installation is expected to take only a half day. If all goes according to plan, the new rain garden will be complete by June 2023.
Maintenance is part of any long-term project. MnDOT programs such as Adopt-A-Highway and Adopt-A-Drain have long relied on volunteer efforts to keep their infrastructure projects in good shape. Now, adopting a rain garden will be added to their practice in Columbia Heights, thanks to the ongoing efforts of HeightsNEXT.
Although the Central Avenue rain garden project is still being explored, MnDOT will continue to gather feedback from the public through surveys and a new website that is coming soon.