Fuse plug

The fuse plug may be a sand-filled container, a steel structure or a concrete 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.

For example, the Warragamba Dam in New South Wales has fuse plugs that are approximately 14m high.

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