Rain Gardens for Clean Streams

1. Rain Gardens
for Clean Streams

2. Did you know?
Up to 70% of pollution in streams,
rivers and lakes comes from storm
water runoff.

3. Planting a Rain Garden…
• reduces the amount of storm water entering
storm drains
• helps reduce the amount of flooding by
keeping water contained so that it can drain
slowly over a period of time
• allows soil to filter out pollutants and reduce
the amount of nonpoint source pollution
entering our streams

4. Nonpoint Source Pollution (NPS)
is caused by many reasons.

5. Excess fertilizers, herbicides, and
insecticides from agricultural lands and
residential areas

6. Oil, grease, and toxic chemicals
from urban runoff and energy
production

7. Sediment from improperly managed
construction sites, crop and forest lands,
and eroding stream banks

8. Salt from irrigation
practices and acid
drainage from abandoned
mines

9. Bacteria and nutrients from
livestock, pet wastes, and faulty
septic systems

10. Rain and snow melt pick up these natural
and human-made pollutants, finally
depositing them into lakes, rivers,
wetlands, coastal waters, and even our
underground sources of drinking water

11. Impervious surfaces (ones that do not allow water
to percolate or drain through soil such as
buildings, parking lots, etc) contribute runoff water
and increase the amount of pollutants in runoff.

12. Rain Garden
A garden designed specifically to
improve water quality.

13. Rain Gardens allow approximately 30%
more water to soak into the ground.

14. Is a rain garden hard to install ?

15. Rain Garden Installation
Before

16. During

17. During

18. After planting

19. After one season

20. Before

21. During

22. After

24. Determine the location
Near the house to catch only roof
run off or out on the lawn to
catch water from the lawn and
roof

25. Location
• A gentle slope (no more than 10%)
– Remember that the garden needs to be dug into a
bowl shape and the greater the slope the deeper the
bowl that will need to be created
• At least 10 feet from your foundation
• Near a downspout or where water naturally
drains
• Away from areas where water already ponds as
there will be little infiltration in this area

26. Planning stage
• Estimate the area which will drain into
your garden (roof and/or lawn)
• Determine the type of soil (sand or clay)
• Gardens planted in sandy soil should be
20-30 % the size of the drain area
• Gardens planted in clay soil should be
60% of the drain area

27. Example
Dylan’s house is 50 feet by 40 feet so the roof area is 2000
sq ft. (50 x 40 = 2000)
He has two downspouts and will plant a rain garden in the
back yard which will collect water from approximately
half of the roof area or 1000 sq ft.
His soil is sandy so the size of the rain garden should be
approximately 250 sq ft. (1000 x .25 = 250)

28. Remember that a rain garden
of any size will help to control
storm water runoff

29. Building the Rain Garden
• Be sure you check with your utility company
before attempting to dig in your yard.
• Lay out the garden with a garden hose or
landscaper’s spray paint.
• Start digging on the uphill side of the garden
• Remember that you will be moving soil from the
uphill to the downhill side of the garden to
create a berm and the bowl shape of the rain
garden

30. Creating the berm
• The berm will be the highest on the downhill
side of the rain garden
• The berm will gradually decrease as you go up
the sides of the rain garden
• After shaping the berm be sure to stomp it down
so that it is well compacted
• Cover the berm with compost/mulch or plant
grass or a dry tolerant native plant to control
erosion on the berm

31. Planting the garden
• Consider the height, color, moisture
tolerance and bloom time of plant material
• Plant in groups of 3, 5 or 7 of the same
variety
• Add rocks, boulders or other ornamental
features to add interest
• Water at least once a week until plants are
established

32. Maintaining the garden
• Weed out any invasive or non native
plants until natives are established
• Stems and seed heads can be left to stand
for winter interest and to attract birds and
other wildlife to the garden
• As spring approaches cut back all standing
growth and compost or discard
• Occasionally the plants should be divided

33. During and after

34. Before and after

35. Why plant a rain garden ?
• To prevent flooding and excess storm
water damage
• To limit the amount of erosion and cut
down on sediment entering our waterways
• To filter out and limit the amount of
pollutants reaching our waterways
• To provide habitat for wildlife

36. Rain Gardens for Clean Streams

37. Financial and other support for this project is provided by the
Pennsylvania Association of Conservation Districts, Inc. through a grant
with the U.S. Environmental Protection Agency’s Section 319 Program.
The mission of the Bucks County Conservation District is to provide for the
wise use, management and development of the county’s soil, water and related
natural resources. This is accomplished with the cooperation of public agencies,
private groups and individuals

38. For more information:
Mary Ellen Noonan
Environmental Educator
Bucks County Conservation District
1456 Ferry Road, Suite 704
Doylestown, PA 18901
215.345.7577
www.bucksccd.org