8/3/2019 Maryland; Rain Garden Project Klinken Residence - City
of Davidsonville
2/8
Stormwater Management Issues
The stormwater from the highlighted roof area is creating
significant run-off during heavyrain, even with the use of rain
barrels that were installed to slow the rainwater discharge.
Rainwater needs to be directed away from the structure and kept
from racing down a slope,
which runs east to west.
A solution would be to install a rain garden for the stormwater
to collect and slowly percolateinto the ground. A secondary rain
garden would serve as an overflow area for situations
where the primary rain garden could not handle the water volume.
Currently, both areas arcovered with sparse grass and located in
full sun.
A percolation test shows that the soil drains fairly quickly
well within the tolerance of 24hours for a hole one foot wide and
two feet deep.
Three downspouts from the roof area will drain into the rain
garden. The calculations are
below:
38 18 684 21 12 252
14 13 182 24 12 288
14 14 196
14 14 196
total sq ft 1258 540
Rain Garden to Roof Ratio 43%
Roof Areas Rain Gardens
The Design
The design of the rain garden will be informal, with river stone
and larger stones to hold the
soil berms and direct the water. The size of the primary rain
garden will be approximately 2
x 12, with a depth of 6 to 12. The overflow area and future rain
garden will beapproximately 24 x 12.
The planting material for the rain garden will be primarily
native species that take full sunand are attractive to birds,
butterflies, bees and beneficial insects, which will help
control
pests in the organic garden adjacent to the rain garden.
Page 2 of 8
8/3/2019 Maryland; Rain Garden Project Klinken Residence - City
of Davidsonville
7/8
Chelone(Turtlehead)
Chelone ob l i qua
Chelone is comprised of a handful of perennials from
NorthAmerica grown for their sturdy dispositions and white, pink,
or
purple flowers that resemble turtle heads. The spikes of
tubular,
2-lipped flowers bloom late in the summer to the middle
ofautumn. Chelone work well in a damp border, bog garden, shade
garden, or at waterside. Blooms from late summer into
fall.Weather resistant. Tolerates boggy soil. Turtleheads need
part
shade or full sun and deep, moist, fertile soil, and can take
heavier or boggy soil as well.
I r i s Vers ico lo r
Generally grows less than 2 feet tall, grows best at waters
edge,but they can also grow in a perennial border with a little
extra
attention to watering. All are hardy at least to Zone 5, and
they
do best in rich, heavy, moisture-retentive soil. These species
are
best established when planted in groups of three to five
fans.Divide and transplant them in early spring or fall, keeping
theroots moist.
Cal tha pa lus t r i s (Marsh m ar igo ld )Native to northern
states and Canada, this little beauty is at home atpond's edge or
along a stream. It is clumping by nature, but can seed into form a
dense groundcover in a consistently moist site. In early
springhundreds of bright yellow buttercup flowers dot the green
carpet ofcordate foliage. Deer usually leave this alone! Found in
marshes,swamps, and wet meadows from North Carolina to
Alaska.Height: 10-12 Inches Spread: 12-18 Inches
USDA Hardiness Zone 3-7Caltha palustris likes moist conditions
and rich soils. It is most at homenear a pond or stream, but can be
happy in a low area that stays wetmost of the time. Marsh Marigolds
do tolerate periods of drought, butwill go dormant, losing all
their leaves.
Rudbeck ia f u lg ida (Black-eyed Susan)Large flowers consisting
of brassy orange-yellow rays surrounding browncones are what make
this plant so popular. It blooms for 7 or 8 weeksbeginning in
midsummer. The flowers top 18- to 30-inch-tall plants that
willreadily self sow in cultivated soils.They are suitable for
mixed borders, meadows, native gardens, open woods,
and large annual displays.Grow in average, slightly heavy but
well-drained soil in full sun to partialshade.
Page 7 of 8
