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Line 55:
Line 55: − + + + − + + − + + + Line 74:
Line 79: − + − + + + Line 111:
Line 118: − + + − − The bottom of a dry pond should be flat to encourage uniform ponding and infiltration across the entire surface. Recommended tolerance on base levels 10 mm in 3m.
→Design
|Drainage Area
|Drainage Area
|Minimum orifice size (see [[flow control]])
|Minimum orifice size (see [[flow control]])
|style="text-align: left|5 Ha (≥10 Ha preferred)
|style="text-align: left|
*5 Ha
*≥10 Ha preferred
|-
|-
|Treatment Volume
|Treatment Volume
|Provision of appropriate level of protection
|Provision of appropriate level of protection
|style="text-align: left|See [[Dry ponds#Volume|below]]
|style="text-align: left|
*See [[Dry ponds#Volume|below]]
|-
|-
|[[Dry ponds#Detention time|Active Storage]]
|[[Dry ponds#Detention time|Active Storage]]
|Detention
|Detention
|style="text-align: left|[[Sedimentation|Suspended solids]] settling 24 hrs (48 hrs preferred)
|style="text-align: left|
*[[Sedimentation|Suspended solids]] settling 24 hrs
*48 hrs preferred for water quality benefits
|-
|-
|Forebay
|Forebay
|Maximize flow path and minimize short-circuiting potential
|Maximize flow path and minimize short-circuiting potential
|style="text-align: left|
|style="text-align: left|
*Overall: minimum 3:1;
*Overall: minimum 3:1
*4:1 preferred
*4:1 preferred
|-
|-
|Depth
|Depth
|Safety
|Safety
|style="text-align: left|Maximum 3 m
|style="text-align: left|
*Maximum 3 m
*Flat bottom to encourage uniform ponding/infiltration (recommended tolerance on base levels 10 mm in 3m)
|-
|-
|Side slopes (See also [[berms]])
|Side slopes (See also [[berms]])
|Buffer
|Buffer
|Safety
|Safety
|style="text-align: left|Minimum 3 m above maximum water quality/erosion control water level
|style="text-align: left|
*Minimum 3 m above maximum water quality/erosion control water level
|}
|}
===Volume===
===Volume===