Topic outline

  • NRCS: Design of Grassed Waterways

    Credit: 3 PDH

    PDH Course Description:

    Grassed waterways are natural or constructed channels shaped to required dimensions and lined with suitable vegetation for stable conveyance of runoff. Grass-lined water conveyance channels are widely used to convey excess runoff water where flows are of a sufficiently short duration to allow the grass to withstand the inundation period and operation is sufficiently infrequent to allow healthy grass cover to be maintained.

    This type of channel may be used for diversions, spillways, and floodways, as well as for waterways to convey local runoff. A constructed waterway is designed to carry the estimated flow without damage to the waterway or its lining, and should be planned and designed to fit the conditions of a particular site.

    Topics:

    • Introduction
    • Assessment of suitability
    • Legal/regulatory considerations
    • Planning and preliminary design considerations
    • Location
    • Slope
    • Cross section shape
    • Vegetation
    • Outlets
    • Sediment control
    • Data collection
    • Design process
    • Initial design parameters: slope, discharge, section, and lining
    • Conditions for stability
    • Sizing channel sections
    • Use of the design tables for parabolic and trapezoidal channels
    • Layout and construction
    • Appurtenant structures
    • Site preparation
    • Excavation
    • Filter fabric barriers
    • Post-construction protection of channel lining
    • Maintenance
    • Removal of sediment
    • Repair work

    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.

    Print the Certificate of Completion

    Intended Audience: This course is intended for Water Resources, Civil, Environmental, Transportation, and other engineers whose job description requires a general knowledge of grass-lined or vegetative water conveyance channel design.
    Publication Source: USDA (Natural Resources Conservation Service)

    Harlan Bengtson PhD, PE

    • Topic 1