UKAEA Culham Water Leak
This project has been a challenge with all the services within the campus area where we located the problem.
The leak has been caused by the old cast iron pipe rusting where is was placed in a concrete duct under the old runway. This is a common practice used across the campus and the third leak we have encountered in the last 2 years.
We were directed to the area by the campus which was in the verge in a gravel area just 6m from all the sub stations which meant everything was checked and triple checked at every stage of the excavation.
We began cutting the road at the location of the crossing and excavating down onto the pipe. To excavate on to the pipe we used a trench box system supplied by Conquip we eventually had 10 of these systems installed along the entire length.
To add to our woes we had running sand so had to install dewatering all along the run supplied by Dewatering Services.
We then found that due to the duct where we located the water was nowhere near the leak location which ended up being on the opposite side of the road and found its way to the weakest point.
On exposing the leak the live main was isolated on a weekend and a new valve fitted on each end.
Of course once the pressure built another section of pipe burst 30m up the road which we had to expose and isolate again.
This thankfully this held though now we had a leak the was 40m from our starting point and crossed over 100 HV electricity cables. For this next phase of works we brought in a friend at Suction Excavation who excavated and exposed all the services in the run with the Vacuum Excavator. This machine extract soil rather than digs in and allows for much safer working around live services and removes the need for hand digging.
We then completed the remaining trench excavation and shingled the base ready to receive the new pipe.
This new pipe is done in Protecta line. All fusion welding and installation of this pipe was carried by our friends at Lawton who also chlorinated the line at the same time.
Once the pipe was installed the location was surveyed by Glandville and we reinstated the trench in layers and completed the tarmac surfacing on top. Tarmac was done by Ashmac who have worked with us a fair bit recently on campus.