These works were part of the Bristol Water AMP 5 Large Diameter Trunk Mains (LDTM) Framework awarded in June 2013 to replace over 45km of trunk mains.
Challenges included working to a tight programme and in constrained urban sites and sensitive archaeological areas.
Murphy was responsible for five main packages of works using a combination of construction techniques including sliplining, close fit structural lining, directional drilling and open cut.
Package 1 - Shipton Mayne to Tolldown: Installation of 6.4km of 450mm PE pipe using close fit structural insertion method inside a 18” Cl main. Installation of 14.2km of 450mm PE pipe using the open cut method.
Package 2 - Knowle to Victoria: Installation of 5.5km of PE pipe ranging in diameter from 315mm to 630mm, using mostly slipline insertion with occasional open cut insertion.
Package 3 - Bedminster to Bristol Bridge: Installation of 6km of 6730mm PE pipe within an existing 27” main by sliplining method.
Package 4 – Barrow to Chelvey: Installation of 6.5km of PE pipe, diameters 355mm, 450mm to 500mm, using the slipline insertion method with some small sections by open cut. Works included 1.7km x 400mm PE within existing 18” steel by closefit structural method.
Package 5 – Filton to Chase reservoir: Installation of 4.2km of 450mm and 560mm PE pipe withing the existing 18” and 24” mains using the slipline insertion method.
By staggering the start dates of each of the work packages we were able to transfer relevant lessons learned and innovations from package to package. This, together with our collaborative approach and extensive experience on similar projects completed for United Utilities, Thames Water and Severn Trent Water, enabled us to complete the project within the tight timeframe.
Murphy entered into the responsibilities of the Bristol City Code of Conduct, ensuring shared values across the team and all stakeholders were kept well informed.
We worked closely with Bristol Water ecological consultants on detailed environmental management plans.
We added value to the project by using our strong relationship with Bristol Water to make recommendations where our expertise could reduce costs.
By collaborating with Bristol water’s repair and maintenance contractor we were able to buy stone and recycled materials together, making significant savings. This collaborative approach also enabled us to work together to minimise disruption to the public and save costs by sharing equipment.