Montel Special Works team were invited to tender for a flow meter chamber installation on one of the most strategic sections of water main in the South Staffs Water network – on the inlet pipework to the Barr Beacon reservoir. The reservoir could not be taken out of commission and during historic water main works at the reservoir in 2011, damage had occurred that lead to the flooding of neighbouring properties and subsequently a large clean up bill and bad publicity.
Integrated Water Services (and SSW) were keen to avoid a similar situation and had great confidence that the Montel Special Works team could deliver the chamber without incident.
The site itself was small with restricted access, unknow services and conflicting historical records about the pipe position, its condition, as well as any other potential obstructions or conditions left from construction of the reservoir back in 1950.
Montel met with IWS on a number of occasions to discuss options and risk. We enlisted our Temporary Works partner to provide a number of options for a number of scenarios that could be encountered. This gave IWS certainty that no matter what was uncovered, Montel and their TW partner would be able to provide a solution that enabled the chamber to be installed. It would just be the complexity and management of design and risk that changed.
Montel’s in house Special Works team are multi skilled and IWS had the confidence that Special Works could deliver the whole project – all aspects from uncovering services and pipework installing the EWS, to steel fixing/shuttering and construction of the chamber, connecting new services and then backfilling prior to surfacing. The Special Works team
Montel then used one of our preferred surfacing contractors to reinstate the surfacing around the chamber, tying back into existing features and ensuring the surface water drainage was more effective than before works started!
Due to the high risk of uncovering unexpected obstructions or conditions, Montel’s Temporary Works supplier was consulted very early in the scheme and an EWS system was chosen that provided the right level of risk cover but could also be adapted easily and quickly to suit conditions.
This included the design and delivery of special fabrication wall mounted brackets and a fixing detail that enabled a 3-sided EWS system installation, to take advantage of every spare mm for the chamber install.
Our skilled team completed the whole installation of the chamber, without incident. This included the install and removal of the EWS, all concreting, all reinforcement and shuttering, all ductwork, backfill reinstatement and installation of specified cover and frame.
The site was finished to a very high standard by our hand laying surfacing partner and we were able to hand over to the client for the next step – installation of the access provisions and mechanical and electrical equipment.
The whole team from client and designer through to Temporary Works and site team were all aware of the potential for change and unknown challenges.
The program and sequencing took account of this shared risk but innovation had to be used when space restrictions meant a traditional 4-sided EWS system couldn’t be used. Existing features and access restrictions limited all other marketplace systems so our Temporary Works designer fully designed and fabricated special brackets that could be fixed to an existing reinforced concrete retaining wall.
The Montel team were also introduced to a new manufacturer of large opening D400 covers and frames that incorporate locking ability and sectional covers. This type of system incorporates a metal frame grouted into rebates pre-formed in the top of the chamber walls, with a load spreading I beam. Then reinforced plastic covers drop into place and are locked into the already secured frame and load spreading beam.
The client is also considering the same covers and frames as upgrades to a number of their existing facilities across the region.