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Road Stormwater Drainage Inlets: Hydraulic Study

Inlet Type: Double Bay (1900mm) With "Abrupt" Transition

On-grade

With & without deflectors

Inlet drawing details
Inlet drawing details

 

 

 

 

 

 

 

75 mm Lid without support

Capture Curves

  • "Abrupt" transition
  • 75mm lid without support

Notes

  • Double Bay (1900mm)
  • 75mm lid
  • Without support to lid
  • Upstream transition: 1500mm
  • Downstream transition: 500mm
  • Inlet depression: 50mm
  • Barrier Kerb and channel: 300mm
  • Crossfall: 3%

Curve Equations

- "Abrupt" transition
- without central support

Q = aXb+cX+d

 curve equations
 

Notes

  • Double Bay (1900mm)
  • 75mm lid 
  • Without support to lid
  • Upstream transition: 1500mm
  • Downstream transition: 500mm
  • Inlet depression: 50mm
  • Barrier Kerb and channel: 300mm
  • Crossfall: 3%

Pictures of test

Standard
1900mm inlet opening  - (75mm lid "abrupt" transition without support)

Longitudinal grade (%) with Approach flow (l/s)

50 mm Lid with central front support

Capture Curves

  • “Abrupt” transition
  • 50mm lid with central front support

Notes:

  • Double Bay (1900mm)
  • 50mm lid with central front support
  • Inlet with deflectors, if grade>=1%
  • Upstream transition: 1500mm
  • Downstream transition: 500mm
  • Inlet depression: 50mm
  • Barrier Kerb and channel: 300mm
  • Crossfall: 3%

Curve Equations

-"Abrupt" transition
-Central front support

Q = aXb+cX+d

50mm lip curve equations

Notes:

  • Double Bay (1900mm)
  • 50mm lid with central front support
  • Inlet with deflectors, if grade>=1%
  • Upstream transition: 1500mm
  • Downstream transition: 500mm
  • Inlet depression: 50mm
  • Barrier Kerb and channel: 300mm
  • Crossfall: 3%

Pictures of test

Single Bay (900mm)

With deflectors

Capture Curves

Notes

  • Single Bay (900mm)
  • With deflectors
  • Upstream transition: 1500mm
  • Downstream transition: 500mm
  • Inlet depression: 50mm
  • Kerb and channel: barrier- 300mm
  • Kerb: channel-300mm,
  • Crossfall: 3%

Curve Equations

Q = aXb+cX+d

curve equations

Notes

  • Single Bay (900mm)
  • With deflectors
  • Upstream transition: 1500mm
  • Downstream transition: 500mm
  • Inlet depression: 50mm
  • Barrier Kerb and channel: 300mm
  • Crossfall: 3%

Without deflectors

Capture Curves

Notes

  • Single Bay (900mm)
  • Without deflectors
  • Upstream transition: 1500mm
  • Downstream transition: 500mm
  • Inlet depression: 50mm
  • Kerb and channel: barrier- 300mm
  • Kerb: channel-300mm,
  • Crossfall: 3%

Curve Equations

Q = aXb+cX+d

curve equations

Notes

  • Single Bay (900mm)
  • With deflectors
  • Upstream transition: 1500mm
  • Downstream transition: 500mm
  • Inlet depression: 50mm
  • Barrier Kerb and channel: 300mm
  • Crossfall: 3%

Sag

Double Bay Sag Test with 50mm lid & 75 mm lid

Capture Curves

Notes

  • Double Bay (1900mm)
  • 75mm lid with no support vertical transition
  • 50mm lid with back watertable support vertical transition
  • Upstream transition: 1500mm
  • Inlet depression: 50mm
  • Kerb and channel: barrier- 300mm
  • Kerb: channel-300mm
  • Crossfall: 3%

Pictures of test