Difference between revisions of "Check dams"

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Check dams are small dams or weirs constructed across a drainage ditch, swale, or channel to lower the speed of concentrated flows for a certain design range of storm events and to promote infiltration.  
Check dams are small dams or weirs constructed across a drainage ditch, swale, or channel to lower the speed of concentrated flows for a certain design range of storm events and to promote infiltration.  


{{Texbox|1=Check dams:
{{Textbox|1=Check dams:
*may be constructed of any resilient and waterproof material, including: rock gabions, earth berms, coarse aggregate or rip-rap, concrete, metal or pre-treated timber. Rocks used in check dams should have median diameter 25-75 mm.  
*may be constructed of any resilient and waterproof material, including: rock gabions, earth berms, coarse aggregate or rip-rap, concrete, metal or pre-treated timber. Rocks used in check dams should have median diameter 25-75 mm.  
*are used, up to 0.6 m in height; the maximum design depth of ponded water must be ≤ 0.6 m.
*are used, up to 0.6 m in height; the maximum design depth of ponded water must be ≤ 0.6 m.

Revision as of 18:14, 27 September 2017

Check dams are small dams or weirs constructed across a drainage ditch, swale, or channel to lower the speed of concentrated flows for a certain design range of storm events and to promote infiltration.

Check dams:

  • may be constructed of any resilient and waterproof material, including: rock gabions, earth berms, coarse aggregate or rip-rap, concrete, metal or pre-treated timber. Rocks used in check dams should have median diameter 25-75 mm.
  • are used, up to 0.6 m in height; the maximum design depth of ponded water must be ≤ 0.6 m.
  • designed for higher flow velocities should have spillways incorporated into their profile, to direct water to the centre of the swale.
  • are usually installed between 10-20 m along the swale. The spacing of dams should not exceed the horizontal distance from the toe of the upstream dam to the same elevation on the downstream dam.
  • should have energy dissipation and erosion control measures installed in the 1 - 2 m downstream. Examples include large aggregate or turf reinforcement


Sizing[edit]

Check dams: Sizing