Rain Gardens

A rain garden is a depressed landscape feature that captures rainwater runoff from roofs, driveways or other hardscape surfaces then slows and cleans the rainwater runoff and allows it to sink back into the ground.

Stormwater is the water that drains off a land area from rainfall and carries pollutants to local creeks, streams, lakes, and ponds and may contribute to flooding during heavy rainfall events. Rain gardens are designed to capture and reduce stormwater runoff and are particularly important in urban areas because developed land (pavement, buildings, and compacted soils) increases stormwater runoff.

Benefits of Rain Gardens

  • Helps stormwater infiltrate into the ground rather than into local creeks
  • Promotes groundwater replenishment in soil conditions that allow for infiltration 
  • Reduces the amount of pollutants from roofs and hardscape from draining into local creeks
  • Slows stormwater runoff; decreasing peak storm water flows and therefore reducing creekside erosion
  • Helps clean the stormwater as it is filtered through the soil
  • Adds an aesthetic landscape feature with many planting and design possibilities
  • Plants used in rain gardens can promote native habitat and food source for hummingbirds, butterflies, and honey bees

Home Rain Garden (PDF)

Rain Garden Graphic

Is a Rain Garden right for you?

Some properties are developed on steep hills and the homes were built with drainage systems designed to move water away from the property and into the storm sewer. Rain gardens may not be appropriate for this type of property. However, homes on flat or slightly sloped properties may be ideal for rain gardens.

  • Do your downspouts from your roof gutters drain onto impervious surfaces such as walkways, driveways or into a piped drain system?
  • Do you have an available garden location, particularly located downhill from a downspout or concrete area around your house?

Frequently Asked Questions

  • Will a rain garden integrate into the landscape design?
    • Rain gardens can be accommodated in almost any residential landscape. The goal of a rain garden is to capture runoff before it reaches a storm drain or water body. Ideally, a rain garden will be located between the sources of runoff and the runoff destination. The size, shape, and plants can be tailored to the location and the amount of water you want to capture. Remember that a rain garden will be periodically wet or dry, but should not hold water more than two to three days.
  • How much will it cost?
    • The cost will depend upon the size of your garden, plant selection, amount of mulch needed, and whether you do it yourself or request a professional. In general, a small residential rain garden will cost between $100 and $300, but could be much more if a contractor in required.
  • How long does it take to build?
  • What tools and materials are needed?
    • Common yard tools like shovels, a tamper or heavy object (like a cement block), and an inexpensive leveling device are all you’ll need. Other supplies include mulch for the garden basin and berm.
  • How much maintenance is required?
    • Basic maintenance includes typical care for new plants the first year (especially regular watering during dry spells) and pruning, thinning and transplanting once plants are established and as the garden matures. Replenish mulch every two to three years.

Rain Garden Resources