Bentley FlowMaster V8i

Hydraulic Analysis for Open Channels, Pipes, Weirs, and Orifices



Use the FEMA-approved FlowMaster to quickly perform hydraulic calculations for dozens of element types, from pipes and open channels to drop inlets and weirs.

Solve for any unknown property, design for any desired characteristic, and produce detailed reports and rating curves on the fly.

FlowMaster’s interface is simple enough to be the easiest model you have ever used, yet so powerful, you will be solving real problems in just minutes.

Top New Features:

Gradually varied flow: Perform gradually varied flow analysis and generate profiles for pipes and open channels.


Project Explorer: Work on multiple projects simultaneously and save them for future use.


More element types: Expand your hydraulic toolbox with new worksheets for parabolic channels and box and elliptical pipes.


Flexible interface: Configure toolbars and dock windows to create work environments that match your workflows.


Customizable graphs: Take complete control over every facet of rating curve plot appearance.



Uses and Benefits of FlowMaster 
Dr Tom Walski, Senior product manager

FlowMaster overview 
video clip

Flood prevention and capacity check
(with FlowMaster and CulvertMaster)

Other water eSeminars

FlowMaster is so easy, you will throw your spreadsheets and nomographs away!

Features and benefits

FlowMaster data sheet (pdf)

Technical requirements and support (pdf)


Special topic:

- Optimize land development project delivery




Inlet and Gutter Hydraulics

Design and analyze grate, curb, ditch, slotted, and combination inlets using calculations based on the FHWA Hydraulic Engineering Circular No. 12 and Circular No. 22 methodologies.

You can consider in sag or on grade conditions with a continuously or locally depressed gutter and calculate water spread and gutter depth for a gutter or pavement section.

Inlet and Gutter Hydraulics
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Pressure Pipe Design

Perform a quick check or design by plugging in the known information and automatically solving for pipe length, start and stop elevations and pressures, discharge, diameter and roughness.

FlowMaster supports the Hazen-Williams, Darcy-Weisbach, Kutter and Manning friction loss methods.


Pressure Pipe Design
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Usability and Data Management

It is often the simplest features that can dramatically improve your productivity. Here are some examples:

  • Copy and paste data from and to Windows applications
  • Relax with unlimited undo and redo
  • Create unlimited worksheets on a single file
  • Enter data once, use it many times with engineering libraries
  • Document multiple design trials on the same file
  • Exercise complete control over units and decimal precision.
  • Use the Project Explorer to save and manage projects
  • Customize the graphical user interface to suit your workflow


Usability and Data Management
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Open Channel Hydraulics

Design and analyze channels, ditches, and free surface pipes of any shape including circular, box, elliptical, parabolic, and irregular channels.

Under uniform flow solve for discharge, normal depth, channel dimensions, slope, or roughness, and compare the results using different friction methods.

Perform gradually varied flow calculations for any free surface flow element, generate profile views from the calculated results, and view the points in tabular form.


Open Channel Hydraulics
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Weir and Orifice Modeling

Size weirs considering discharge, weir coefficients, and crest, headwater and tailwater elevations for the following types:

  • Rectangular
  • V-notch
  • Cipolletti
  • Broad crested
  • Custom

Design rectangular, circular and generic orifice structures accounting for submergence with rating tables of graph for tailwater elevation.


Weir and Orifice Modeling
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Graphing and Reporting

Using FlowMaster's comprehensive reporting capabilities, you can quickly create summary reports or complete records of your analysis and design.

Build customized tabular reports, graphs, cross-sectional plots, performance curves, and rating tables to support smarter decision-making.


Graphing and Reporting
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