Rain gardens are a natural way to filter stormwater by removing heavy metals or sediments before it goes into waterways.
Bioretention is the process in which contaminants and sedimentation are removed from stormwater runoff. The main objective of natural rain garden media is to attenuate peak runoff and remove stormwater runoff pollutants.
They are also designed to hold a small amount of stormwater to slowly release it into waterways over an extended period of time.
There are a lot of technical factors that go into designing a rain garden, such as:
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Location
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Depth, dimension and spacing
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Drainage and Infiltration rate
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Media mix and media depth
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Surface finishing and plant selection
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Overland flow path
Azwood supplies a natural bioretention filter media required for a rain garden. Natural rain garden media provides a temporary holding capacity during a rain event which helps slow down the flow of water going into catchments. The water is filtered through the bioretention media which absorbs contaminants before the stormwater flows into the ground, pipes, drains and streams, and eventually to the sea.
The plants chosen for a rain garden system have been specifically picked for their ability to absorb nitrogen, phosphorus and other heavy metals.
The suitability of plant species will depend not only on their ability to remove heavy metals, but also on their capacity to tolerate conditions that may negatively impact plant growth. For example, plants in bioretention systems may be exposed to both wet and dry conditions, ponding and loading of fine sediments.
The environmental benefits include:
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Carbon storage and recycling nutrients.
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Provides habitat and greater biodiversity.
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Purification of air and reduces air pollution.
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Connection to nature.
Read more about Azwood® bioretention natural rain garden media.