Page 19 - 7166 - Rain Garden Handbook

Where NOT to Locate PLAN 1 13

a Rain Garden

DON’T LOCATE YOUR RAIN GARDEN:

1. Within 10 feet of a building foundation—to avoid water getting into
basements and crawl spaces. David Hymel

2. Over utilities—to prevent extra expense and hazardous conditions, make sure
to have all utilities located and marked before digging. Utility companies
typically locate and mark power, gas, phone, water, and other lines and
facilities. Contact utility locate services by calling 811. DIAL 811—
3. Near the edge of steep slopes or bluffs—the additional water soaking into Call Before You Dig!
the ground on steep slopes can cause landslides or unwanted settling. In
general, slopes should be less than 10% for a conventional rain garden. If Be sure to have all your utilities (gas, power,
the rain garden is within 50 feet of a slope that is more than 10%, consult water, communications, etc.) located and marked as you
with a geotechnical engineer. plan where to build your rain garden and before digging to
test for soil and groundwater conditions. In addition to the
4. Near a septic tank, septic drainfield, or reserve drainfield area—generally, 811 service that primarily locates utilities in public rights-
if uphill of a septic system, provide at least 50 feet and if downhill provide of-way, utility locate businesses can be retained to locate
at least 10 feet between the rain garden and the existing or planned septic and mark public and private utilities. You also can contact
system. Consult your local health department for specific setback requirements. the utility providers directly for more information. Note:
Utility locates expire after 45 days, and the property owner is
5. In low spots that do not drain well—these areas may be helpful for naturally responsible for calling 811 to have utilities re-marked after that.
slowing and storing stormwater on your property, but poorly draining
depressions will not support rain garden plants very well.
6. In areas that would require disturbing healthy native soils, trees, and other
vegetation—these areas already do a good job of filtering and storing stormwater.
7. Where there is high groundwater during the winter—if groundwater rises to
within one foot of the bottom (excavated soil surface) of your rain garden
during the winter (highest level), you should consider another location.
In areas of high groundwater, a rain garden will not drain or function properly.

8. Near wells—your rain garden must be set back a minimum of 100 feet from
drinking water wells.

David Hymel