Hydraulic Design of Spillways

Vincent D. Reynolds, MBA, P.E.

Course Outline

Spillways are used to convey water from a reservoir. They are often used to provide flood-control as with other flood systems or as the only flood-control facility. Several design variables will be considered in this course that relates to the function and size of spillways. Measures will be discussed that are useful in controlling erosion at the outlet of the spillway.

This course will provide information regarding the design of Spillways and a discussion of its engineering properties. These course materials are based solely on the report “Hydraulic Design of Spillways” as found on the website of the Army Corps of Engineering.

This course includes a multiple-choice quiz at the end, which is designed to enhance the understanding of course materials.

Learning Objective

At the conclusion of this course, the student would have learned the following:

• The design variables for spillways;
• How to identify an underdesigned crest;
• How to the Darcy-Weisback equation to determine energy loss;
• How to design stilling basins for optimum performance;
• How to determine the resistance coefficient;
• How to determine the roughness coefficient;
• How to define cavitations;
• Which factor affects the capacity of spillways;
• The three configurations for the spillway approach;
• How to determine the freeboard;
• The causes of horizontal forces on gates;
• How to determine the K value for stilling basins;
• The use of baffles;
• How cavitations can damage a stilling basin;
• How to determine the minimum radius of a roller bucket;
• How to determine the cavitations index;
• How to identify subcritical flow;
• How to determine the Froude number;
• The four categories of spillways; and
• How to find the value of ß.

Intended Audience and Benefit

This course is intended for anyone with an interest in Spillways, structural engineering, geotechnical engineering, hydraulics, power generation, hydrology, hydrogeology or anyone wanting to know more information regarding Hydraulic Design of Spillways.

Course Introduction

Spillways are essential in conveying water from reservoirs. This aids the reservoir in controlling water flow for the purposes of flood control, irrigation, creating bodies of water and for hydroelectric power.

This course will discuss the various engineering properties of spillways. Several basic equations will be presented that are used to design the size and type of spillways.

Course Content

This course will examine the use of Spillways under several different circumstances. It will provide useful information to determine the size and area of spillway s needed to efficiently convey water runoff. The course materials are based solely on the engineer manual “Hydraulic Design of Spillways” as found on the website of the Army Corps of engineers. This course includes a multiple-choice quiz at the end, which is designed to enhance the understanding of course materials.

Hydraulic Design of Spillways:

Note: Chapters 1 through 7 and Appendix C are the sections that are required reading to complete the quiz.

Course Summary

The information presented in this course could be used to enhance the student’s knowledge of hydraulic design of spillways. Using this knowledge could enable to reader to design safer spillways, and reservoirs among other developments that utilize spillways.

As always good judgment and good engineering judgment is always paramount in any situation. Utilizing good judgment and the knowledge gained in this course can provide much more efficient Spillways.