Calf Hey Reservoir is in Haslingden Grane, the glaciated upper portion of the valley of the River Ogden, in the north east of the West Pennine Moors, close to the town of Haslingden. It was constructed in 1860, the second of the three reservoirs in the valley, the others being Holden Wood Reservoir (1842) and Ogden Reservoir (1912).
Around the middle of the nineteenth century, Haslingden Grane contained a thriving community. About 1500 people lived in the valley, some 600 of them in a village close to the main road to Blackburn, and the rest in farms and hamlets scattered around the valley. “Abandoned Communities ..... Haslingden Grane” (Link
) gives a good account of the building of the reservoirs and the effect this had on the people of Grane Valley and the hamlet of Haslingden Grane. By the 1920s almost everyone had left Haslingden Grane. There had been a gradual decline in the opportunities for employment within the valley, and in addition the creation of a string of three reservoirs accelerated the process of depopulation. The village and most of the farms lay above the reservoirs, but as the Bury and District Water Board had bought most of the land in the lower parts of the valley residents were obliged to leave when their tenancies came to an end and farmers had to forfeit much of their best land.
Today, the reservoirs and the moorland scenery make for a popular place for walkers; there is a car park at Clough Head (SD 750231 Link
United Utilities) with an information centre and cafe and another car park at the end of Calf Hey Road (SD 754228).