Water & Land Use

Raingardens

A rain garden is a landscape tool that can provide many environmental benefits while adding color and beauty your yard. Rain gardens provide a beautiful solution for yards with poor drainage. A strategically placed and well-designed garden captures excess rainwater from roofs, gutters, and paved areas and uses plants and special soils to absorb the water. Gardens can replace muddy low spots with beautiful planted areas.

33 Ridge after rain

Environmental Benefits

Rain gardens…

  • Collect and filter stormwater from roofs and paved surfaces.
  • Help recharge natural groundwater.
  • Reduce soil erosion.
  • Reduce non-point source pollution to our streams and the Chesapeake Bay.
  • Provide valuable habitat and food source for birds, butterflies and other pollinators.

    • Economic Benefits

    Rain gardens…

  • Reduce outdoor water use for landscaping. Once installed rain gardens seldom need any watering.
  • Improve drainage in yards potentially eliminating the need for very expensive underground drainage improvements.
  • Reduce backups in the stormwater system so GHI will not have to spend as much time pumping out flooded crawlspaces.

    • Rain gardens can be planted in nearly all yard types. Low, sunny spots provide the best sites for maximizing colorful flowers, but many attractive plants are available for shadier spots. GHI has prepared a helpful brochure that provides tips on planning, building, planting and maintaining a rain garden in GHI and a plant list of some recommended plants that will grow in our area.

    Demonstration Garden Sites

    To showcase rain garden techniques in our community GHI is developing demonstration rain gardens at various sites around town. Drop by to check out rain gardens in action.

    • Ridge Road: 33 court

      During summer of 2006, GHI staff created two demonstration gardens along Ridge Road at the intersection of Hamilton Place near 33 court of Ridge. These gardens - one shade and one sun - capture rooftop runoff from a block of rental garages. Prior to installing the rain garden, this site would frequently flood causing erosion and contribute to excessive water in nearby crawl spaces. Now the gardens provide an attractive mix of shrubs, grasses and wildflower that add vibrant color to the court. Funding for this demonstration project and educational brochure was provided by the Chesapeake Bay Trust

      before
      after

    • Plateau Place: 6 court

      During summer of 2007, GHI staff partnered with CPE, Inc. to build a specially designed 600-square foot rain garden near the parking lot at 6 Plateau Place during the major renovation of the parking lot in the court. This high-visibility sight was selected for a demonstration garden due in large part to the damaged caused by storm water runoff into the streams and forest area downhill from the parking lot. Prior to construction of the garden, all rainfall landing on the 12,000 square foot parking lot flowed directly to a storm water drain pipe that dumped into the GHI Forest Preserve. This meant for every 1” of rainfall more than 6,700 gallons of water gushed out of the pipe causing extensive erosion (insert attached “Plateau Erosion” picture) to the stream areas below.

      Read more about the planning and implementation of this project in detail >> Acrobat .pdf.

      The new garden is designed to capture the majority of the rainfall runoff from the lot and allow it to slowly soak into the ground instead of causing erosion in the streams. The mulch layer and garden plants will also help to filter out pollutants such as anti-freeze and oil from cars and sediment, nutrients, and ice melt products from the lot instead of sending it directly to the stream and ultimately the Chesapeake Bay. This garden provides all of these benefits while supporting an attractive mix of trees, shrubs, wildflowers, and decorative grasses that will attract birds and butterflies and add vibrant color to the court. The garden also contains a special by-pass drain to allow excessive water from heavy rain storms or large snow melt to exit the garden without causing overflow into the parking lot area.

      Funding for this demonstration project, project sign Adobe .pdf, and educational brochure was provided by the Chesapeake Bay Trust .

      before
      Common area and storm drain by lot preconstruction.
      during
      Excavated garden area.
      Filter cloth installed over gravel layer.

      Installing special rain garden soil mix over filter cloth.
      Garden after final grading before planting.
      after
      Garden after fall planting.
      Garden during first year of summer growth!

    Publications

    • Rain Gardens: A Landscape Tool to Improve Water Quality Acrobat .pdf
      This colorful and informative "how-to" brochure is designed specifically for GHI members and recommends plants that work well in our community. Funding for this brochure was provided by the Chesapeake Bay Trust .
    • Recommended Plant List for Rain Gardens in GHI Excel .xls
      This excel spreadsheet lists a number of flowers, grasses, shrubs and even trees, that will generally grow well in rain gardens in our area. This list is not complete and all plants will not work in all yard conditions but it is a good starting point.
    • Rain Garden Presentation.
      GHI has developed an informative PowerPoint presentation on rain gardens that provides detailed information on designing and constructing rain gardens, tips on selecting locations, photos of suitable plants and more. Due to its size, this file is not available online. To obtain a copy contact GHI at 301-474-4161 x132.
    • Native Plant Nurseries Adobe .pdf
      (courtesy of Montgomery County DEP)
      Drawn from a variety of native plant society lists, these are reputable dealers for both retail and wholesale markets in the Metropolitan Washington area, including Maryland, the District of Columbia, Virginia, Pennsylvania, and West Virginia.
    • Rain Gardens: Harvesting the Heavens Adobe .pdf
      (courtesy of Montgomery County DEP)
      For imaginative landscapers, rain gardens may represent the perfect marriage of heaven and earth. Specially-designed garden areas help to receive and store rainfall, using that moisture to nourish an oasis of interesting native plant communities reminiscent of lush stream banks and freshwater marshes.
    • Rain Gardens in Wisconsin Acrobat .pdf
      An excellent brochure created by the University of Wisconsin and Wisconsin DNR that demonstrates detailed rain garden construction techniques. Note: Some plants recommended in this brochure will not prosper in Maryland and are not readily available.

    Links

    • www.rainscapes.org
      A resource page on rain gardens, rain barrels and more from Montgomery County Department of Environmental Protection
    • Residential LID
      An interactive web site for viewing a number of Low Impact Development (LID) tools for homeowners such as rain gardens, conservation plantings, grass swales, and more.
    • Rain Gardening
      A good resource page for learning more about rain gardens and how to construct one in your yard.
    • Raingardens.org
      Resource page on general rain garden information.

    For more information, contact Matt Berres .