Critical Valve Exchange
St. Pauls Road, Hemel Hempstead
Equipment
We arrived on site and agreed with Affinity Water (AW) to excavate with Vacuum Excavator, (Vac-ex) given close proximity to existing 21″ water main.
Exposed 4” valve – found spindle in valve was very worn and valve is letting water by.
Initial investigations revealed that original work instruction did not accurately assess work to be carried out. This is a common dynamic and requires accurate diagnostic appraisal on site by our highly skilled teams, working in collaboration with (AW) engineers.
The original work instruction requested that CLC repair the existing valve or potentially replace it, this would ultimately require the water main to be shut down and therefore lead to interruption of supply to customers. AW & CLC were able to use its considerable innovation and collaboration skills to execute the works without causing any interruption to supply.
Following primary investigative work, it became apparent sheet piles and safety shoring would be required due to deep excavation work. The site was made safe and arrangements were made to deliver all equipment the following day.
Equipment
Arrived on site with the JCB and Vac-ex. Squared up excavation to clear round 21″ main and faulty valve.
CLC Beaver tail delivered shoring timbers and sheet piles to site. Second delivery of sheets was needed as excavation exceeded 3.3 meters depth.
Boarded excavation using ply sheets and Heras safety fencing.
Equipment
Following installation of sheet piling and shoring, CLC examined the faulty valve to reveal leak via gland on valve.
Our skilled staff worked in collaboration with AW to develop anchoring bars, specifically fabricated by authorised CLC engineers in Harlow (12hr turnaround).
This innovation proved critical in reducing the leak.
The fabricated components were used to anchor the main before the freezing off process and exchange were completed. This innovative process originated through our skilled team, using their considerable problem-solving abilities and vast experience to ensure a swift economic repair of the leak. Collaboration with our clients, AW and our fabrication engineering service partners was also key factor.
A secondary problem was identified, relating to the planned freeze of the main. CLC dispatched its Hydrant Wizard technology to avert problems with the freezing process.
Recycled shingle placement and plastic sections installed for new valve spindle box chamber. In addition, CLC reused all existing as dug material to ensure our circular economy strategy was executed, saving considerable reinstatement and vehicle movement costs.