Page 47 - 7166 - Rain Garden Handbook
P. 47
Build
Create a Flat, Place the Rain 2 41
Level Bottom Install the Inflow Garden Soil Mix
If applicable, install any pipes, runnels, roof downspout extensions, Place the soil mix in the rain garden about 6 inches at a time and
or other features that will carry water to your rain garden. This should walk on each layer to lightly tamp down. Fill the soil up to a level that
be done at the end of excavation and before placing your rain garden provides the desired ponding depth (6 or 12 inches is recommended)
soil mix. Install pipes so that they slope toward the rain garden for and overflow containment area (6 inches above the overflow minimum).
the most efficient water flow. Downspouts and waterworks designed Be sure to keep the bottom of your rain garden flat and level.
as attractive garden elements and art features can add a nice touch.
Don’t use flexible pipe to deliver water to the rain garden. Rigid pipe
is easier to maintain and doesn’t settle as much over time, which
can impede drainage. Be sure to test that water flows freely to the
rain garden and adjust placement as necessary before permanent
installation. Remember if water is directed through a swale sloping
more than 2%, consider providing small rock check dams every 5 to
10 feet to slow the water (see photo below).
Teresa Brooks
David Hymel
Erica Guttman Bob Spencer Bob Spencer

