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Rain Gardens

Rain gardens are a great way to enhance water quality by filtering many pollutants out of the stormwater before it reaches groundwater or local waterways. So if you’re planning to do some landscaping, consider creating a rain garden as an attractive way to add natural habitat into your backyard while also being a better environmental steward.


What is a Rain Garden?

A rain garden is a shallow depression landscaped with plants and designed to catch rainwater runoff from impervious surfaces such as driveways, walkways and roofs.


Why are Rain Gardens Important?

If appropriately designed, rain gardens can soak up and the runoff from rooftops, roadways, and other impervious surfaces and keep it out of the City’s stormwater system. Rain gardens provide habitat for animals and protect aquatic life from pollutants otherwise entering our streams and wetlands through the stormwater system.


Key Features of Rain Gardens

  • A specially designed soil mix planted with a variety of suitable trees, shrubs, grasses and other plants
  • Designed to retain stormwater

Some Benefits of Rain Gardens

  • Keeping pollutants from reaching local waterways
  • Reducing flooding problems
  • Providing habitat for beneficial birds and insects
  • Refreshing local groundwater
  • Low-maintenance landscaping with no need for chemicals
  • Can create an attractive and creative landscaping piece  

Green Stormwater Infrastructure Typical Details for Rain Gardens

The Green Stormwater Infrastructure Typical Details have been developed for use by City staff and private developers. Refer to the Stormwater Management Manual for associated design criteria and sizing guidance. 


Typical Details for Rain Gardens include:


Figure 011  Rain Garden - Planting Zones

Figure 012  Rain Garden Section

Figure 013  Rain Garden Piped Inlet

Figure 014  Rain Garden Inlet Swale

Figure 015  Rain Garden Piped Overflow

Figure 016  Rain Garden with Swale Overflow