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Road Stormwater Drainage Inlets: Hydraulic Study

Inlet Type
Double Bay (1900mm):

On-grade

With deflectors

Capture Curves

Notes:

  • Double Bay (1900mm)
  • With Deflectors
  • Upstream transition: 1200mm
  • Downstream transition: 600mm
  • Inlet depression: 85mm
  • Barrier Kerb and channel: 300mm
  • Extended apron: 300mm
  • Crossfall: 3%

Curve Equations

   Q = aXb+cX+d

curve equations

Notes

  • Double Bay (1900mm)
  • Precast lintel lid
  • With Deflectors 
  • Upstream transition: 1000mm
  • Downstream transition: 600mm
  • Inlet depression: 75mm
  • Barrier Kerb and channel: 300mm
  • Extended apron Kerb: 300mm, 
  • Crossfall: 3%

Pictures of test

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

Without deflectors

Capture Curves

Notes:

  • Double Bay (1900mm)
  • Without Deflectors
  • Upstream transition: 1000mm
  • Downstream transition: 600mm
  • Inlet depression: 75mm
  • Barrier Kerb and channel: 300mm
  • Extended apron: 300mm
  • Crossfall: 3%

Curve Equations

Q = aXb+cX+d

curve equations

Notes

  • Double Bay (1900mm)
  • With Deflectors 
  • Upstream transition: 1000mm
  • Downstream transition: 600mm
  • Inlet depression: 75mm
  • Barrier Kerb and channel: 300mm
  • Extended apron Kerb: 300mm, 
  • Crossfall: 3%

Pictures of test

Sag

Capture Curves

Notes

  • Double Bay (1900mm)
  • Precast lintel lid
  • Without Deflectors 
  • Upstream transition: 1000mm
  • Inlet depression: 75mm
  • Barrier Kerb and channel: 300mm
  • Extended apron Kerb: 300mm, 
  • Crossfall: 3%