South Yorkshire Times September 10, 1949
Conisbrough Reservoir Gets “Spring Clean”
National Coal Board employees at Denaby have been busy this week giving the 650,000 gallons capacity Northcliff Reservoir on Conisbrough Crags, a spring clean.” The reservoir, supplied from a 335ft. deep borehole at Cadeby Main Colliery, provides the whole of Denaby with a domestic and industrial water supply and also both Denaby and Cadeby pits.
Every day, Denaby and the two collieries use approximately 340,000 gallons of water. This week, while the reservoir has been empty, they have been drawing the supply from an emergency tank adjoining the reservoir, and N.C.B. officials stated on Tuesday that they expected the township would be on this emergency supply for five days.
On Saturday, N.C.B. employee began to empty the reservoir. By 1 a.m. on Sunday the switch-over to the emergency tank was made. There was then only 15 inches of water in the 113ft. diameter reservoir. On Tuesday, a “South Yorkshire Times” reporter found a team of 10 men scraping the sides of the reservoir and brushing clean the floor.
The remaining 15ins. of water had been pumped out of the reservoir on Monday.
Floor and sides are being treated with a chlorine mixture and it is hoped to commence refilling the reservoir this week-end. The walls of the reservoir are 12ft. deep and the normal level of the water is maintained at a depth of 11 ft