Second rain garden planned for Thoreau School

Construction will take place Sat., June 1, 9:00 am to 1:00 pm.  
At Thoreau School, along Nakoma Rd.
Cookies and lemonade will be served.  
Bring a shovel and gloves.


At Thoreau School, runoff from the roof and a paved playground was causing a large gully to form in Nakoma Park.

Parents and the Parks Division stepped up to the plate--to help solve the problem.

A group of parents and teachers, spearheaded by parent Stephanie Robinson, built a large and beautiful garden just downstream from the playground.

Stephanie received several grants to buy plants.  Parents and teachers involved the children in planning and construction.  Every child had a hand in planting.

Meanwhile, the Parks Division sent heavy equipment to repair the gully.  A ways down the slope, they built a channel to redirect runoff towards a basin of stone riprap.

Unfortunately, the rain garden was badly damaged by snowplows during the winter.This spring, the damage was repaired.

But runoff problems persist.  Garden #1 isn't large enough to absorb all the runoff.  Below that garden, substantial new erosion is starting above where repairs were made.  So additional rain gardens are needed.

Last fall, Jack Nolan volunteered to build a second rain garden at Thoreau, for his Eagle Scout project.  I offered to help, since it's a large and challenging project for an Eagle Scout.  The Friends of Lake Wingra provided a grant of $1,500 towards construction costs.

Recent progress

Yesterday, Jack and I dug a 1/4 scale model at Vilas Beach, learning a few things about design of berms. We learned how to take the substantial slope at our location into account.

We also inspected rain garden #1.  Recent rains have eroded a breach in the downstream berm (below, center).

Today, we went to Edgewood College to try to get permission to use silt socks leftover from construction on campus.

Next, we went to Thoreau School and used yellow rope to lay out the boundaries of the new rain garden, #2.  Due to slope and limited space, we are going to build two basins.  And each basin will be terraced, with a silt sock across the middle, so less excavation will be required.  The gardens will be located in the turf area in the photo below (right rear).

While we were laying out the garden, a large snapping turtle arrived to inspect our work.  Traffic was backed up while she crossed Nakoma Rd.

Some of the plants have been picked up from Prairie Nursery.  The rest will be picked up from Agrecol on June 5.

A few challenges remain
  • Edgewood college is donating silt socks left over from construction.  They are bulky--can anyone with a pickup truck help move them?
  • Four blue cohosh plants from Praire Nursery didn't emerge from dormancy, and died.
  • Some plants ordered from Agrecol weren't available, and had to be substituted. 
  • We haven't decided what kind of mulch to use.  Most mulch floats--not good for a rain garden.
  • Next week, Jack will work with Liz McBride to design locations for the plants.
Planting is scheduled for Saturday, June 8.  Help is needed!  (Rain date--Sunday June 9.)

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