I’ve seen some puzzled faces and been a bit puzzled myself as I’ve watched the rain gardens being built as part of our Prior/Goodrich RSVP project. Today I gave Forrest Kelley from the Capitol Region Watershed District a call and asked a few questions. I thought I’d share what I learned.
There are actually two different types of rain garden being built on Lincoln as part of the RSVP project. One is the shallow depression that will be planted with native grasses and flowers, the second is a deeper tree trench.
The tree trenches have been “maximized for water retention” (in other words, made pretty deep) in order to feed the trees that will be planted there. These tree trenches are also the rain gardens being planted with regular grass sod. Right now they make the boulevard look a bit like a mini-golf course, but that will change once the trees are planted and grow larger.
The native plant gardens will not get sod, they will remain a dirt boulevard for now. They will probably get some soil treatment (a few inches of special soils), but the plantings won’t arrive until Spring. Forrest said a date in the spring is being worked out by CRWD and Saint Paul, and we’ll get word of what it is once it is set, but that date is likely not till next Spring.
All of the rain gardens will get the small concrete ledge in the boulevard, next to the curb cuts. These help manage erosion and give us a place to gather up soil that might otherwise get out of the garden.