Basins finished for Thoreau School rain garden

On Saturday, June 1, from 9:00 to 1:00, about 17 people helped dig two basins for the second rain garden at Thoreau School. This included 10 people from Jack's scout troop.

One parent of a scout helped to shape and level the berm.

The basins were completed, then protected against rain with silt socks and tarps.  Excess dirt was piled, for later pickup by the School District personnel.

We ran into an extensive root system while digging the upper basin.  We decided not to cut any roots larger than 1" in diameter.

This slowed us down, and reduced the volume of the basin.

On Sunday, Liz McBride met with Jack to begin planning (in detail) where the plants will go.

On Monday, Liz began to put markers into the basins, indicating zones and plant locations.

At this point, we realized the basins weren't as large as originally planned.  Where to put the excess plants?   David figured out  a design for a third rain garden located upstream,  in dense shade under the basswood tree (see photo above, rear).  This area will be planted with our most shade-tolerant plants.  Instead of digging a basin where roots are dense, we'll hold the water here with silt socks.  While the plants are becoming established, silt socks will divert runoff from this area.

Liz drew up a handout of instructions for planting day.  A teacher is putting up posters outside Thoreau classrooms, soliciting parent and student participation.  One class at Thoreau will "adopt" the rain garden.

On Tuesday, David and Jack laid an erosion control blanket over the berm, to protect against forecast rain.  David and Jack were "on call," to visit the site in case of heavy rain, to shore up erosion controls.

With the help of Rich (Jack's dad) and John Tan, we picked up 3 more gargantuan silt socks from Edgewood, to use in constructing the third area.

One of the silt socks was still alive, and looped a big tentacle around Jack, before he could dodge it.

On Wednesday, David picked up 480 plants from Agrecol, cramming them into every corner of his vehicle.  They all looked healthy.

The garden survived the light rain of Wednesday and Thursday just fine.  Rain garden #1 absorbed all the runoff.

On Friday, David will finish placing stakes, indicating plant locations.

Planting will take place on Saturday, June 8, from 9:00 to 1:00.  Scouts will participate.  Some parents and children from Thoreau School will drop by to help, but no classes will participate.  This time of year is too busy for Thoreau teachers, and Liz was concerned that we weren't quite ready for so many helpers at once.

Several issues still need to be addressed in detail...
  • The garden is down to subsoil.  We may use top dressing of compost--after planting--to enrich it.
  • What kind of mulch?  Most kinds float.  We may use grass clippings, (which form an interlocking thatch) or the contents of Edgewood silt socks.  Mulch and compost will be applied after planting day.
  • Details of protecting the gardens from heavy storms.  We'll wait to see how rain flows through them, then protect the overflow areas. 
  • Watering hardware and schedule.  There is a spigot, though at some distance.
  • The basswood tree needs trimming to increase light levels.
Photos from construction day

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