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Road Stormwater Drainage Inlets: Hydraulic Study

50 mm Lid, Central standard support (setback)

With & without deflectors

Capture Curves

Notes:

  • Double Bay (1900mm)
  • 50mm lid with central standard support (setback)
  • Inlet with deflectors, if grade>=1%
  • Upstream transition: 1200mm
  • Downstream transition: 600mm
  • Inlet depression: 85mm
  • Barrier Kerb and channel: 300mm
  • Crossfall: 3%

Curve Equations

Q = aXb+cX+d

curve equations

Notes:

  • Double Bay (1900mm)
  • 50mm lid with central standard support (setback)
  • Inlet with deflectors, if grade>=1%
  • Upstream transition: 1200mm
  • Downstream transition: 600mm
  • Inlet depression: 85mm
  • Barrier Kerb and channel: 300mm
  • Crossfall: 3%

Sag

Double Bay (50mm lid)

Capture Curves

Notes:

  • Double Bay (1900mm)
  • 50mm lid with central standard support (setback)
  • Without deflectors
  • Upstream transition: 1200mm
  • Inlet depression: 85mm
  • Barrier Kerb and channel: 300mm
  • Crossfall: 3%

Drawings of test

Inlet Type Double Bay (1900mm), ("Abrupt" Transition 1200mm):