Capacities of Sewer Pipes

Carrying capacity of sewer and wastewater pipes - gpm and liter per second

The diagrams below can be used for design of sewage and wastewater gravity conveying systems.

Sewage Pipe Capacity - Imperial units - gpm

sewage wastewater pipe capacity gpm

Sewage Pipe Capacity - SI Units - liter per second

sewage wastewater pipe capacity liter per second

Note! - the charts are based on clean plastic pipes - calculated with the Manning formularoughness coefficient 0.015 and fill 50%.

Example - Capacity of a Sewer Pipe

The capacity of a 4 inch sewer pipe with decline 0.5% is aprox. 25 gpm (1.6 liter/s).

  • 1 gal (US)/min = 6.30888x10-5 m3/s = 0.227 m3/h = 0.06309 dm3(liter)/s = 2.228x10-3 ft3/s = 0.1337 ft3/min = 0.8327 Imperial gal (UK)/min

Decline and Slope

Calculate between different units for decline and slope

d = 8.33 s(in/ft)

   = 100 s(ft/ft)

   = 100 s(m/m)

   = s(ft/100ft)         (1)


d = decline (%)

s = slope

Example - % Decline

1/8 in/ft slope can be transformed to % decline as

d = 8.33 (1/8 in/ft)

   = 1.04 %

Related Topics

  • Fluid Flow and Pressure Drop - Pipe lines - fluid flow and pressure loss - water, sewer, steel pipes, pvc pipes, copper tubes and more
  • Water Systems - Hot and cold water service systems - design properties, capacities, sizing and more

Related Documents

Tag Search

  • en: sewer, capacity, pipe, carrying
  • es: alcantarillado, la capacidad, la tubería, llevando
  • de: Kanalisation, Kapazität, Leitung, Durchführung

Search the Engineering ToolBox

- "Search is the most efficient way to navigate the Engineering ToolBox!"

Engineering ToolBox - SketchUp Extension - Online 3D modeling!

3D Engineering ToolBox Extension to SketchUp - add parametric components to your SketchUp model

Add standard and customized parametric components - like flange beams, lumbers, piping, stairs and more - to your SketchUp model with the Engineering ToolBox - SketchUp Extension/Plugin - 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!

Translate the Engineering ToolBox!
About the Engineering ToolBox!