8,254
edits
Changes
Jump to navigation
Jump to search
m
→Design
Line 81:
Line 81:
#Minimum depth: 1 m;#Sized to ensure non-erosive velocities leaving forebay; #Maximum area: 20 % of total permanent pool#Overall: minimum 3:1; #Forebay: minimum 2:1#5:1 For 3 m above and below permanent pool; #Maximum 3:1 elsewhere#Minimum 450 mm; #Preferred pipe slope: >1%; #If submerged, obvert 150 mm below expected maximum ice depth#Minimum: 450mm outlet pipe; #Preferred pipe slope: >1%; #If orifice control used, 75mm diameter minimum; #Minimum 100mm orifice preferable #Provided to approval of Municipality; #Provision of maintenance drawdown pipe preferred
|Pre-treatment
|Pre-treatment
|style="text-align: left|
|style="text-align: left|
*Minimum depth: 1 m;
*Sized to ensure non-erosive velocities leaving forebay;
*Maximum area: 20 % of total permanent pool
|-
|-
|Length-to-Width Ratio
|Length-to-Width Ratio
|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;
*Forebay: minimum 2:1
|-
|-
|Permanent pool depth
|Permanent pool depth
Line 102:
Line 102:
|Safety
|Safety
|style="text-align: left|
|style="text-align: left|
*5:1 For 3 m above and below permanent pool;
*Maximum 3:1 elsewhere
|-
|-
|Inlet
|Inlet
|Avoid clogging/freezing
|Avoid clogging/freezing
|style="text-align: left|
|style="text-align: left|
*Minimum 450 mm;
*Preferred pipe slope: > 1 %;
*If submerged, obvert 150 mm below expected maximum ice depth
|-
|-
|Outlet (See also [[flow control]])
|Outlet (See also [[flow control]])
|Avoid clogging/freezing
|Avoid clogging/freezing
|style="text-align: left|
|style="text-align: left|
*Minimum: 450 mm outlet pipe;
*Preferred pipe slope: > 1 %;
*If orifice control used, 75 mm diameter minimum;
8Minimum 100 mm orifice preferable
|-
|-
|Maintenance access
|Maintenance access
|Access for backhoes or dredging equipment
|Access for backhoes or dredging equipment
|style="text-align: left|
|style="text-align: left|
*Provided to approval of Municipality;
*Provision of maintenance drawdown pipe preferred
|-
|-
|Buffer
|Buffer