Bentley CulvertMaster V8i

Culvert Hydraulic Analysis and Design




The FEMA-approved CulvertMaster is hands down the best tool available for solvingculvert hydraulics problems. Incredibly flexible, fast, report-ready, and stress-free, CulvertMaster builds on the input you have on-hand while providing what you are missing.

Analyze systems with multiple barrels, different shapes and sizes, special tailwater considerations, and roadway overtopping considering watershed data, culvert characteristics, and even weir geometry.

Automatically compare and incorporate several design trials into complex hydraulic analyses and evaluate the results using the built-in Culvert Designer utility.

CulvertMaster will pay for itself on your first project as it streamlines complicated culvert hydraulics and delivers the results you need.

Fast: Quickly deliver robust, report-ready culvert designs. CulvertMaster builds on the input you have onhand providing you with any unknown design variable such as headwater depth, discharge, or culvert size.

Easy: From simple, single culvert sections to complex, multibarrel culverts with roadway overtopping, CulvertMaster helps you evaluate existing culverts and compare numerous design options with ease.

Reliable: Use the built-in FHWA HDS-5 methodology, SCS and rational hydrology, and robust gradually varied flow hydraulics to deliver culvert designs that will stand the test of time.



Uses and Benefits of CulvertMaster 
Dr. Tom Walski, Senior advisory product manager


CulvertMaster overview video clip

Flood prevention and capacity check
(with CulvertMaster and FlowMaster)

Other water videos



Choose to generate reports, calculate rating tables and plot curves:

  • Comprehensive reports contain both input conditions and detailed calculation information
  • Tabular views of your culvert systems exhibit the effects of varying system characteristics
  • Graphical views and reports are stunning: focus on a single culvert, or compare multiple elements on the same graphic.
Choose to generate reports, calculate rating tables and plot curves
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Rainfall and Watershed Analysis:

  • Directly enter the peak flow rate if you already know it
  • Choose between the widely accepted Rational Method or SCS Graphical Peak Method to automatically determine the flow at your crossing
  • Input an unlimited number of watershed sub-areas, along with their corresponding runoff coefficients
  • Let CulvertMaster automatically determine the total area and weighted runoff coefficient

Rational Hydrology: Enter equations, tables, or Hydro-35 data to create your Intensity-Duration-Frequency (IDF) curves for Rational Method storm events. You can reuse your IDF rainfall data for projects that are in the same region.

SCS Hydrology: Choose an SCS type I, IA, II, or III storm for calculating the peak flow rate based on the SCS Graphical Peak Method.


Rainfall and Watershed Analysis
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  • Solve for whatever you need to know: headwater elevation, discharge—even the size of the culvert.
  • Use the widely accepted U.S. Federal Highway Administration (FHWA) Hydraulic Design of Highway Culverts (HDS-5) methodology for performing both inlet control and outlet control computations.
  • Determine hydraulic grade lines using the best gradually varied flow algorithms in the industry.
  • Work with flow profiles that are subcritical, critical, supercritical, horizontal, and even adverse. CulvertMaster can handle the toughest backwater and drawdown conditions, including composite profiles and hydraulic jumps.
  • Handle free-surface flow, pressurized flow, and transitions accurately and efficiently.
  • Model multiple section types, shapes, and profile geometries at the same crossing. Available section types include boxes, circular sections, arches, horizontal ellipses, and vertical ellipses.
  • Add a roadway or broad-crested weir to your embankment to check overtopping conditions.
  • Choose from several available tailwater channel shapes, including rectangular, triangular, trapezoidal, and irregular shapes.
  • Automatically solve for the overtopping break point.
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Simulation Type

Quick Culvert Calculator: For simple culverts with known characteristics, use the Quick Culvert Calculator to plug in the data you know and solve for what you need.

Culvert Analyzer: For more complex systems with multiple barrels, different shapes and sizes, special tailwater considerations, and roadway overtopping, make use of the Analyzer. Incorporate whatever data you have, including watershed data, tailwater conditions, culvert characteristics, and even weir geometry.

Culvert Designer: Use the Designer to compare several proposed options. Incorporate these design trials into complex hydraulic analyses and evaluate the results. 


Simulation Type
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Learn CulvertMaster in just a few minutes with the built-in interactive tutorials.

The data entry and manipulation are flexible and straightforward. On top of it all, you'll never have to look at another blurry nomograph or HY-8 blue screen again. 

Navigate your design and analysis models quickly, using tabbed dialog "worksheets" to edit watershed data, tailwater conditions, profile information, and more.

All of your designs and analyses for a project can be organized within a single file.


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Project Management

CulvertMaster provides users with numerous data management tools, such as:

Engineering Libraries: Lets users specify common parameters that can be shared across projects. Three libraries are available for materials, section size, and culvert inlet.

Rainfall Data: Modelers can specify their rainfall data either by using a Rainfall table or a Rainfall equation.

FlexUnits: Engineering units can be managed and precision displayed for each attribute on the fly using quick right-click menus.


Project Management
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