Real Time Control Testing Facility 

The laboratory facility consists of a 30 m long sewer pipe, 0.2 m in diameter with three manholes and a final CSO chamber 10 m downstream of the third manhole.

Each manhole is 1.5 m high and 1 m in diameter. The CSO chamber is 1.4 m by 0.5 m with a full width end weir. Water is pumped into the system by two submersible pumps capable of a combined output flow of 50 L/s, with the flow rate controlled by butterfly valves after each pump. A further butterfly valve, at the downstream end of the 0.2 m diameter “sewer” pipe, controls the water depth in the CSO chamber. CSO spills exit back to the main sump. Manhole 1 is fitted with a device to minimise any vortices/flow irregularities caused by the pump or upstream pipework. A weir in manhole 2, with 0.3 m crest width, was constructed 1.3 m above the manhole invert level to replicate additional upstream storage (i.e. represented as flow spilling over the weir).

A flow control device (FCD) (Steinhardt HydroStyx Electric) with 0.2 m gate diameter is installed in the Manhole 3 and controlled by a Fuzzy Logic control algorithm. The gradient of the pipe is 1 in 500 to ensure adequate drainage. The facility includes two level monitoring sites (LMS) in manhole 3 (upstream of Gate) and one site in the CSO. Each LMS consists of a single pressure transducer which measured water level relative to the manhole invert level, at 0.1 Hz.