Topic outline

  • Hydraulic Design of Storm Sewers using Excel

    Credits: 4 PDH

    PDH Course Description:

    Storm sewers are widely used to carry away runoff from storms, primarily in urban areas. The hydraulic design begins after the locations of the manholes for the system have been determined. Between each pair of manholes the storm sewer will have a constant slope and diameter.

    The hydraulic design process results in determination of an appropriate diameter and slope for each length of storm sewer and determines the depth of the bottom of the pipe at each manhole. The overall procedure and each step will be presented and discussed. Example calculations for a single length of storm sewer between two manholes will be performed and an example of calculations between successive manholes will be done using Excel.

    Topics:

    • determine the value for runoff coefficient for a drainage area with known land use, SCS soil group, and approximate surface slope.
    • find the rainfall intensity for specified storm duration and return period at a specified location if given an I-D-F table or graph for that location.
    • estimate overland flow travel time for a drainage area using the Manning Kinetic equation.
    • estimate channel flow travel time using Manning’s Open Channel Flow Equation.
    • estimate peak runoff rate from a drainage area using the Rational Method.
    • use Method I and Method II as outlined in this course to calculate design diameter and slope for a length of storm sewer between two successive manholes.
    • determine the velocity and flow rate in a circular pipe flowing partially full if enough information is available to calculate the full pipe velocity and flow rate.
    • put together the above skills to carry out the overall hydraulic design of a length of storm sewer between two successive manholes.
    • use Excel to make storm sewer hydraulic design calculations for lengths of storm sewer between successive manholes.

    To take this course:

    1.) Enroll in Course:
    Click below to enroll:
    (must be logged into your user account)


    2.) Study: Once enrolled, click below to begin the course:

    Download the Study Guide

    3.) Test: Once you've thoroughly read the course materials, please click below to take the final examination.

    Take the final exam

    4.) Certificate: A passing grade of 70% or higher on the exam, is required to receive the certificate of completion for this PDH course.
         NOTE: After the exam is completed, you will need to return to this page, in order to print (download) the certificate of completion.

    Important Notice:

    Please ensure that a payment has been remitted, prior to completing Step 4 (printing your certificate of completion).
    Additionally, check your receipt to confirm that your plan is active and has not expired. 
    Certificates issued without a completed payment may be considered invalid by your board of licensure.


    Print the Certificate of Completion

    Note from the Author: After completing this course, you will be able to carry out hydraulic design of storm sewers to determine diameter, slope and depth of invert at each manhole for the length of storm sewer between two successive manholes. You will also be able to set up an Excel program to carry out hydraulic design for successive lengths of storm sewer.
    Intended Audience: hydrologists, civil engineers, hydraulic engineers, highway engineers and environmental engineers.
    Publication Source: Harlan H. Bengtson, PhD, PE

    Harlan Bengtson PhD, PE

    • Topic 1