Rosebush Reservoir provides a raw water supply to Preseli Water Treatment Works. There was a requirement to up-grade the pipework and valves within a 17 metre deep shaft and tunnel which allows the raw water to be drawn off for treatment at Preseli Water Treatment Works.
To minimise the carbon footprint of this scheme a siphon system was installed to allow water to be supplied to Preseli Water Treatment work during the improvement works. The siphon system negated the use of mechanical pumps which would have been required to run 24 hours per day. A temporary scaffold structure was designed and installed to support the twin 400mm syphon pipework down the spillway to the existing draw off mains. Underpressure connections were undertaken on connect the temporary siphon pipework to the live 450mm draw off water main. Once the siphon was operational the pipework, valves, access platforms and ladders were removed and replaced within the 17m high tower.
Young Bros were appointed by Dwr Cymru Welsh Water as Principal Contractors to deliver the scheme.