A fuse plug is a collapsible dam installed on spillways in

dams A dam is a barrier that stops or restricts the flow of surface water or underground streams. Reservoirs created by dams not only suppress floods but also provide water for activities such as irrigation, human consumption, industrial use, ...

to increase the dam's capacity. The principle behind the fuse plug is that the majority of water that overflows a dam's spillway can be safely dammed except in high flood conditions. The fuse plug may be a sand-filled container, a

steel Steel is an alloy of iron and carbon that demonstrates improved mechanical properties compared to the pure form of iron. Due to steel's high Young's modulus, elastic modulus, Yield (engineering), yield strength, Fracture, fracture strength a ...

structure or a

concrete Concrete is a composite material composed of aggregate bound together with a fluid cement that cures to a solid over time. It is the second-most-used substance (after water), the most–widely used building material, and the most-manufactur ...

block. Under normal flow conditions the water will spill over the fuse plug and down the spillway. In high flood conditions, where the water velocity may be so high that the dam itself may be put in danger, the fuse plug simply washes away, and the flood waters safely spill over the dam. Fuse plugs are used in many dams throughout the world. For example, the Warragamba Dam in

New South Wales New South Wales (commonly abbreviated as NSW) is a States and territories of Australia, state on the Eastern states of Australia, east coast of :Australia. It borders Queensland to the north, Victoria (state), Victoria to the south, and South ...

has fuse plugs that are approximately 14m high.

References

Dams {{dam-stub