Increasing Reservoir Storage or Spillway Capacity using Fusegates: Fid-Bau Portal

Increasing Reservoir Storage or Spillway Capacity using Fusegates

J.J Hite / C Mifkovic

PURPOSE: The purpose of this Technical Note is to provide basic information on the operation of fusegates and their use for flood control projects. A brief description of a site specific fusegate model study performed for the U.S. Army Engineer District, Sacramento is also included. INTRODUCTION: Fusegates were invented in 1989 as a simple and safe system to increase reservoir storage or spillway capacity. The system has been patented by Hydroplus International in the United States, Europe, and other countries. Hydroplus has installed fusegates on over 30 dams worldwide, including an irrigation dam in New Mexico. The fuse gate is a nonmechanical structure consisting of three main components; a bucket, a base, and an intake well connected to a chamber in the base (Figure 1). For a retrofit on an existing spillway, a portion of the ogee crest is removed and provided with a flat surface. If only an increase in spillway capacity is needed, the crest of the fuse gates is set near the crest elevation of the original ogee. To increase storage, the crest of the fusegates is set higher than the original ogee crest elevation. The fuse gates are set side by side on the flat surface across the width of the original spillway. For new construction, a flat surface is provided initially. BASIC OPERATION: At most installations, the fusegate functions like an aerated labyrinth weir for discharges up to the design discharge. For discharges greater than the design flow, flow enters the intake wells and into the chamber at the base of the gate. The intake well (shown in Figure 1) is located directly above the base of the fuse gate. The intake well can be located remotely and connected to the base of the gate using conduits. Accumulation of seepage water in the bottom chamber is prevented by providing each chamber with two drains.