Centerville, DE

This pair of gardens was installed to reduce erosion on the property and pollution in a nearby stream.

• Funded by: the Flintwoods (landowners)
• Cost:
• Designers: Mike Campbell and Sue Mrugal
• Size: upper garden of 1350 square feet; lower garden of 600 square feet
• Runoff Area: 25 acre agricultural field
• In progress: 2005

Construction:

• Depth: slightly below the existing grade; excavated to a depth of four feet.
• Fill: A foot of sand was put in the bottom of the pit to increase infiltration; the rest of the hole was filled with a 30% sand and 70% topsoil mix.
• Overflow: Water from upper garden runs through a riprap outlet, across a meadow to lower garden. Overflow from lower garden disperses into wet woodland.
• Plant Material: In the upper garden warm season grasses will be planted this fall. The lower garden will be a mulched bed with native trees and shrubs.

Lessons Learned:

• A close relationship between designer and contractor is important, as a contractor inexperienced with rain gardens may not realize the importance of every aspect.
• To reduce soil compaction and damage to soil texture resulting in impermeability, do not work the soil when it is wet and avoid heavy machinery on the garden site. If the soil does get compacted, have the contractor fluff it back up.

Education:

• Private tours of the gardens are offered
• Flintwoods is hoping that Delaware Nature Society will add the rain gardens to the educational classes they already offer on the property.
• Hopefully long-term inspection of three monitoring tubes in the upper garden that measure quantity of groundwater will further the educational value of this project.

AVAILABILITY: Private tours only, reservations required. Appointments can be made by e-mailing the following address.

CONTACT: Bill Haldeman Flintwoods@mindspring.com