On this Ordnance Survey Map published c.1954 the reservoir was run by New Mills UDC. It is shown on later OS maps as Jordan Bank Reservoir. When built in 1926, Harrymoor water was supplied by gravity from the Kinder Bank Reservoir known as the Division Tank - I've called it KB3.
Mellor Reservoir is now not supplied by Severn Trent and is be supplied by water from United Utilities from Wybersley Treatment Works.