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===Check dams===
===Check dams===
{{:Check dams}}
{{:Check dams}}
==Planting Design Considerations==
*Grasses and herbaceous species with dense root structure cover should be favoured along the bottom of the swale for their ability to increase infiltration, stabilize soils, retain pollutants and assist with suspended solids.
*The plant material on the slopes of grass channels must be capable of withstanding periodic inundation in addition to extended periods of drought. Species include grasses and groundcovers, as well as low shrub species.
*Plants along the exterior of this zone act to slow the flow during stormwater events, reducing sedimentation and increasing infiltration. The root structure of this plant material also acts to reduce erosion.
*Selected grasses or groundcovers for grassed swales should be allowed to grow between 75 to 150 mm to assist in filtering suspended solids from stormwater. Therefore these species are either shorter naturally, or tolerate periodic mowing.
*When grasses grow taller they have a tendency to flatten down from the water flow.
*Fine, close-growing species provide for good soil stabilization.
*Species are salt-tolerant due to the typical location of grass channels along roadways and parking lots.
*Erosion protection such as river stone or riprap will be required to dissipate the energy from incoming concentrated flow.
*The channel must be vegetated immediately after grading. Preferably, the swale should be planted in the spring so that the vegetation can become established with minimal irrigation.