New Rock Colliery

Overview

Sunk in 1819 on the Nettlebridge side of the Somerset coalfield, with a winding shaft and a pumping and upcast shaft. It reached the Globe seam at 166 metres and was later extended to the Garden Course at 360 metres — 1,182 feet, down a shaft only four feet six inches across. Frederick Spencer took it over in 1886 and developed it without deepening the shafts, driving an incline from the bottom of the winding shaft into the Great Course seam with compressed-air haulage and building an electric power house in 1904 to help the ventilation. By 1935 it was raising 3,500 to 5,000 tons a month with about 700 men. Its narrow shaft defeated the National Coal Board’s attempts to modernise it, so the Board reopened the neighbouring Strap Pit and connected the two in 1957 as Mendip Colliery. Both New Rock shafts ceased work in September 1968.

History

New Rock was sunk in 1819, a short distance north of the Strap, Nettlebridge and Sweetleaze group of pits south-west of Stratton-on-the-Fosse, and takes its name in contrast to the older Old Rock colliery at Nettlebridge, sunk in 1786 and closed in 1873. The official list of collieries at work in 1880 returns it as "New Rock, Nettlebridge, New Rock Coal Co." The colliery’s making was Frederick Spencer, who took it over in 1886. Rather than deepen the shafts further — an expensive business in a field where shafts were narrow and coal was thin — he drove an incline from the bottom of the winding shaft into the Great Course seam and worked it with a compressed-air haulage system, and made other improvements including an electric power house in 1904 to assist ventilation. He was substantial enough by 1896 to be recorded as the owner of the Bishop Sutton pit as well, in the Pensford basin twenty miles north. By 1935 output ranged from 3,500 to 5,000 tons a month and the mine employed about 700 men. Under the National Coal Board from 1947 further improvements were made, notably an electric winding engine on the pumping shaft. The Board wanted more from New Rock, which had considerable reserves, but was restricted by the small diameter of the shaft. Rather than develop it, it decided to reopen the neighbouring Strap Pit — capped and disused since 1870 — and link it to New Rock and Sweetleaze, making one more efficient mine. The Strap capping was removed and the shaft cleared at a cost of £47,000, the shaft bottom reached in 1956, and the workings connected to New Rock in 1957, at which point the combined mine became Mendip Colliery. It was fully operational in 1964.

Geology

New Rock and the neighbouring Moorewood pits are among the few places in the Somerset field where coals of the Lower and Middle Coal Measures were worked — only in the southern part of the Radstock Syncline was that possible. The Strap shaft, a mile or so south-west, reached 560 metres and proved six major coal seams; it is the deepest shaft in Somerset. New Rock’s own shaft went first to the Globe seam at 166 metres and later to the Garden Course at 360, with the Great Course reached not by deepening but by an incline driven from the shaft bottom. The whole field is tightly folded and faulted by the Variscan movements, its seams thin and its coal good, which is the standing difficulty every pit here worked against.

Geological setting: Faults and Fractures (well documented example), Sedimentary Beds and Seams (well documented example)

Workings

Two shafts — one for winding, one for pumping and as an upcast — the winding shaft only four feet six inches in diameter, which is the fact that governs everything else about the pit. It wound all its coal up that shaft well into nationalisation. Spencer’s answer to reaching deeper coal without deepening a narrow shaft was to drive an incline from the shaft bottom into the Great Course seam and haul on it with compressed air. The Coal Board’s answer, sixty years later, was to stop trying: it reopened Strap Pit, cleared its shaft at £47,000, and connected the workings so that New Rock’s reserves could come out somewhere wider.

Closure

Mendip Colliery — New Rock, Strap and Sweetleaze combined — became fully operational in 1964, but severe labour shortages in the area, transport difficulties and the lack of a rail link brought bad losses in 1968. The decision was taken to close, both New Rock shafts ceased work in September 1968, and by 1969 any available material was being sold as scrap. Only Kilmersdon and Writhlington were left in the Somerset field, and both closed in 1973.

What remains

The colliery is gone and the ground reclaimed. The Somerset coalfield as a whole leaves its evidence in building remains, spoil heaps and tramway earthworks rather than standing plant, and New Rock is no exception. No dated photograph of the site as it now stands was found that is freely licensed.

Nothing specific to the colliery has been identified.

Nearby mines

• Kilmersdon Colliery — 3.5 km N
• Norton Hill Colliery — 4.1 km N
• Old Mills Colliery — 4.3 km N
• Writhlington Colliery — 4.7 km N
• Clandown Colliery — 6.6 km NE

Straight-line distance, within 15 km. Show on the map.

Recorded claims

Individual factual claims, each attached to the source(s) that support it below. Where sources disagree, both are kept.

• The official list of collieries at work in 1880 returns the pit as "New Rock, Nettlebridge, New Rock Coal Co." ¹
• New Rock was sunk in 1819 and consisted of a winding shaft and a pumping and upcast shaft; the shaft was initially dug to the Globe seam at 166 m and later extended to the Garden Course seam at 360 m. The winding shaft was 4 ft 6 in in diameter and the maximum depth 1,182 ft. ^2,3
• Frederick Spencer took the mine over in 1886 and developed it without deepening the shafts, driving an incline from the bottom of the winding shaft into the Great Course seam worked by compressed-air haulage, and building an electric power house in 1904 to assist ventilation. ³
• By 1935 output ranged from 3,500 to 5,000 tons a month and the mine employed about 700 men. ³
• The National Coal Board found New Rock restricted by its small-diameter shaft despite considerable reserves, and reopened the neighbouring Strap Pit instead — the capping removed and the shaft cleared at a cost of £47,000, the shaft bottom reached in 1956 and the workings connected to New Rock in 1957, when the combined mine became known as Mendip Colliery. ³
• Severe labour shortages, transport difficulties and the lack of a rail link caused bad losses in 1968; the decision was taken to close, and by 1969 any available material was sold as scrap. ³

Photographs & further reading

Sources

1. (secondary) List of coal mines UK 1880 — Coalmining History Resource Centre
2. (secondary) Somerset Coalfield — Wikipedia
3. (primary) Coal mining — Foundations of the Mendips — British Geological Survey

Record created: 6 September 2026 · Last researched: 6 September 2026