Mill Dam Forming Road Bridge Over River Ter And Associated Wheel Chamber And Water Pump To The South

The Mill Dam forming a road bridge over the River Ter, along with an associated wheel chamber and water pump to the south, dates back to 1767, with the water pump added around 1870. It is constructed of red brick in English bond, with the bridge's abutments reinforced with concrete. The structure spans approximately 40 meters in a northeast-southwest direction, featuring two stilted round arches over the main channel and a smaller stilted round arch over an overflow channel at the northeast end.

The wheel chamber and pump are located immediately south of the southwest end of the bridge. On the southeast face of the dam, there is a stone tablet inscribed 'J.S. 1767' and a bronze plaque stating 'Essex County Council 1914'. The mill and its associated works were built by John Strutt. The second Lord Rayleigh later demolished the mill but installed a pump in the original wheel chamber to provide drinking water to the village.

The system included a cast iron pipe of square section that led the intake through a control valve operated by a bevel gear, driving an undershot cast iron wheel with 24 curved vanes. Drinking water was piped from a spring at Swan Pond, located 250 meters to the south, to three galvanised horizontal cylinders bolted to a cast iron chest containing three non-return valves. The waterwheel powered a crankshaft mounted on three split bearings, with three connecting rods and pistons. The water then passed through a domed cylindrical collector and a gravity-operated safety valve to a series of standpipes, with an overflow in Wat Hobbs Lane. This system remained operational until around 1915, when it was replaced by a larger engine-driven pump needed to supply a military camp. As of the last inspection in March 1985, the waterwheel and pump were mostly intact, missing only one broken vane, one piston, a connecting rod, a big-end, part of the control gear, and oil cups for the bearings.