Woodhead Reservoir

The construction of the Woodhead Embankment was ambitious and fraught with difficulties. The embankment was to be about 90 ft in height; it was sealed to the underlying impermeable rock by a central impermeable clay puddle core or curtain. This was supported on each side by selected strong earth material, and then gravel to form a slope of 1 in 1 upstream and 1 in 2 downstream. The upstream would be pitched, and faced in stone. The turnpike would pass over the crest. Drinking water would be extracted by means of a tunnel from several metres below the water level, while when full, excess water would pass over the overspill or waste weir.

Work started in 1848. The Heyden Viaduct, now known as the Woodhead Bridge, was completed in 1851, and turned over to the Salters Brook turnpike road that year. The Woodhead embankment was 20 ft from completion. Discharge valves had been supplied by Messrs Armstrong and Co, of Newcastle upon Tyne. There was some leakage but on 10 May 1854 the Woodhead Reservoir was declared complete, with the exception of remedying the leak. To stop the leak, borings had been made, and ash injected under pressure in the hope it would act as a sealant. In 1858, it was concluded that this would not work; the Etherow valley was on multiple fissures relating to a fault that was causing movement in the soft beds…