Sump

A collecting pool at the bottom of a mine shaft, or at any low point underground, where water gathered so it could be pumped or hauled to the surface.

Historical usage

Sumps are as old as underground mining itself — wherever a shaft or working ran below the water table, water draining or seeping in had to collect somewhere before it could be removed, and the lowest accessible point naturally became that collecting place. In some English mining districts a sump was known instead as a 'lodge'.

How it worked

Water flowing through a mine's workings drained by gravity to the lowest point — typically the bottom of the main shaft — where it collected in the sump; from there it was raised to surface or to a drainage adit by pumps, or in earlier periods by hand or horse-powered lifting.

Why it was used

Without a sump to collect drainage water in one place, a mine had nowhere for pumps to draw from — an unmanaged mine could quickly flood, so keeping the sump pumped out was a basic, continuous condition of keeping any deep working dry enough to work at all.

Risks & limitations

An unattended or malfunctioning sump could fill unnoticed, and a sump was also simply a deep, often unlit body of water at the base of a shaft — a fall into one, especially after an accident elsewhere in the mine, could easily be fatal.

Disasters associated with this term

Included only where MineArchive's own research gives a reasonable evidential basis, with the nature of the relationship stated — not every disaster where this term might plausibly apply.

• Great Laxey Mine scaffold collapse (direct cause)
  The four men killed in 1904 fell into the sump at the bottom of the workings and drowned.

Sources

1. (secondary) Mine dewatering — Sump Pumping — SlideShare
2. (secondary) Sump — Wikipedia

Record created: 22 August 2026 · Last researched: 22 August 2026