Engineering ToolBox - Resources, Tools and Basic Information for Engineering and Design of Technical Applications!

This is an AMP page - Open full page! for all features.

California Pipe Flow Metering Method

Sponsored Links

With the California Pipe Flow Metering Method the discharge from the open end of partially filled horizontal pipes discharging freely into the air can be measured.

The discharge can be calculated as

q = 8.69 (1 - a / d)1.88 d2.48                           (1)


q = discharge (ft3/s)

a = distance in the plane end of the pipe - from the top of the inside surface of the pipe - to the water surface (ft)

d = internal diameter of pipe (ft)

The equation is empirical and can be used for pipes in the diameter range 3 - 10 in

  • 1 mm = 0.00328 feet
  • 1 ft = 0.3048 m = 12 in = 0.3333 yd = 30.48 cm = 304.8 mm
  • 1 ft3/s = 0.0283168 m3/s = 101.9 m3/h = 28.32 dm3(litre)/s = 60 ft3/min = 373.7 (UK)/min = 448.9 gal (US)/min (US gpm)

California Pipe Flow Example

In the discharge on a horizontal 4 inches PVC sewer pipe the distance from the top inside pipe to the water flow is 3 inches (0.25 ft). The inside diameter of the PVC pipe is 4.069 in (0.34 ft)

The discharge can be calculated as

q = 8.69 (1 - (0.25 ft) / (0.34 ft))1.88 (0.34 ft)2.48      

   = 0.049 ft3/s

California Pipe Flow Calculator - Imperial Units

d - inside diameter of pipe (ft)

a - distance between top inside pipe to water surface (ft)

Load Calculator!

California Pipe Flow Calculator - Metric Units

d - inside diameter of pipe (mm)

a - distance between top inside pipe to water surface (mm)

Load Calculator!

Sponsored Links

Related Topics

Flow Measurement

Flow metering principles - Orifice, Venturi, Flow Nozzles, Pitot Tubes, Target, Variable Area, Positive Displacement, Turbine, Vortex, Electromagnetic, Ultrasonic Doppler, Ultrasonic Time-of-travel, Mass Coriolis, Mass Thermal, Weir V-notch, Flume Parshall and Sluice Gate flow meters and more.

Sanitary Drainage Systems

The purpose of the sanitary drainage system is to remove effluent discharged from plumbing fixtures and other equipment.

Related Documents

Sponsored Links


Search Engineering ToolBox

  • the most efficient way to navigate the Engineering ToolBox!

SketchUp Extension - Online 3D modeling!

Add standard and customized parametric components - like flange beams, lumbers, piping, stairs and more - to your Sketchup model with the Engineering ToolBox - SketchUp Extension - enabled for use with the amazing, fun and free SketchUp Make and SketchUp Pro . Add the Engineering ToolBox extension to your SketchUp from the Sketchup Extension Warehouse!


We don't collect information from our users. Only emails and answers are saved in our archive. Cookies are only used in the browser to improve user experience.

Some of our calculators and applications let you save application data to your local computer. These applications will - due to browser restrictions - send data between your browser and our server. We don't save this data.

Google use cookies for serving our ads and handling visitor statistics. Please read Google Privacy & Terms for more information about how you can control adserving and the information collected.

AddThis use cookies for handling links to social media. Please read AddThis Privacy for more information.

This website use cookies. By continuing to browse you are agreeing to our use of cookies! Learn more