Construction of the new 6.5km pipeline began in summer 2019 and is planned to finish by spring 2022. It will connect Bristol’s existing trunk sewer in Lawrence Weston to the Frome Valley relief sewer near Cribbs Causeway and will direct waste more efficiently around North Bristol to our water recycling centre in Avonmouth.
The majority of the sewer will be constructed by tunnelling underground using a tunnel boring machine, reducing the need to dig trenches. We will even be tunnelling underneath the M5 motorway and Network Rail’s Henbury Loop freight railway.
We are working with contractors J. Murphy & Sons Ltd to construct the tunnel and lay the pipework.
The North Bristol relief sewer forms an essential part of our long-term sewerage strategy for the next 100 years.
Learn more about the project by watching this video and click the drop-down options below to find out relevant information for each area of North Bristol where we’ll be present.
Construction of a temporary site compound and tunnel entrance in the hillside below Oasis Academy Bank Leaze began in August 2019. The tunnel boring machine (TBM) was scheduled to launch from this site in March 2020. However, the launch was postponed due to the Covid-19 pandemic. The TBM was eventually launched in June 2020 and has now begun its journey northwards to construct the main section of relief sewer.
This site is now operating 24hrs a day as tunnelling is a continuous operation, however HGV movements and deliveries are restricted and will not be permitted between the hours of 7pm and 7am. There may be some noise disruption while this work is carried out, but every effort will be made to minimise this and complete the work as quickly as possible.
A smaller section of sewer to connect the main tunnel with the existing Bristol network has now been constructed behind Saltmarsh Drive, through the playing fields of St Bede’s Catholic College and behind Attwood Drive. Construction of this section and reinstatement was completed in autumn 2020.
Customers will notice a large increase in vehicle movements through Lawrence Weston as we receive material deliveries and remove construction waste. We will do everything we can to minimise traffic disruption and are coordinating our vehicle movements with local schools.
Extensive work has been required in the Henbury area to connect the existing sewerage network to the new relief sewer.
In August 2020 we completed the construction of a 30-meter deep shaft at our site compound in Crow Lane Open Space near Tormarton Crescent. The tunnel boring machine, which was launched from our main site in Lawrence Weston during the summer of 2020, successfully arrived at the deep shaft in April 2021. This provided the opportunity for maintenance to be carried out on the tunnel boring machine before it continued its journey towards Cribbs Causeway.
In June 2021 the tunnel boring machine cleared the railway line that passes underneath Wyck Beck Road and has left the Henbury area. The shaft compound in Crow Lane Open Space has been cleared of plant and equipment and our contractors will return later in 2022, once the main tunnel is completed, to fit out the deep shaft with mechanical and electrical equipment. The shaft has been capped with a steel cover to keep it secure and the area will continue to be patrolled, although it will still serve as an emergency exit from the tunnel during construction and so the temporary track will remain through the Open Space for the time being.
To make the connection between the existing network and the new sewer, we have constructed an additional pipe through Crow Lane Open Space and the playing field of Henbury Court Primary Academy. Most of this pipe was installed using a ‘no-dig’ pipe jack technique to avoid open trenching.
Watch what we’ve been up to in Henbury…
The reinstatement of some areas of Crow Lane Open Space is nearly finished following our pipelaying work. Delays unfortunately occurred during May 2021 due to the weather but we hope to complete all we can for this year by the end of July 2021. Rebuilding of the Henbury Road wall (near the ford) is complete and the gate will be replaced. We will also be replanting the original, plus an additional 12 new apple trees in the orchard. The reseeding contractor will start work within Henbury Court Primary Academy very soon, which will allow the temporary palisade gates to be taken down.
Members of the public are still able to use Crow Lane Open Space during our work and we are continuing to provide safe crossing points along our temporary access track.
The new connecting sewer pipe and manhole have been successfully constructed in Catbrain and all temporary measures, such as the culvert crossing ramp at the bottom of Catbrain Hill, have been removed.
The reinstatement work between Catbrain Hill and Medlar Close has unfortunately encountered delays. These are due to ongoing discussions with the current landowner about the construction of the new stone wall on land that will eventually be adopted by South Gloucestershire Council. While these discussions are ongoing, the verge has been tidied up which involved removing the heras fencing, erecting a temporary post and wire fencing and replacing the topsoil. Work to complete the reinstatement and construction of the stone wall will be complete as soon as possible.
Meanwhile, work in the former Filton Airfield to construct the 30-metre deep shaft was complete in November 2020 and we are now making preparations on site for the tunnel boring machine to arrive in the shaft in August 2021. Most of these preparations are taking place in the bottom of the shaft but a mobile crane will be required to facilitate access in and out of the shaft.
The site compound will become active from the middle of July 2021 and 24-hour working will be required for approximately three weeks. Nearby residents of Catbrain Hill and Medlar Close will be notified of the work and all reasonable efforts will be made to minimise disruption.
Once the tunnel boring machine has passed through the shaft it will continue northwards to its final destination at The Bristol Golf Club. The airfield site compound will then be idle again until our contractors return in 2022, once the main tunnel is completed, to fit out the deep shaft with mechanical and electrical equipment.
Our tunnel boring machine is scheduled to complete its journey and arrive at The Bristol Golf Club in early 2022, where it will be taken out of the ground in a site compound on the golf course.
The site compound is constructed on the edge of the 15th fairway of the golf course, close to the 15th hole and the 17th tee.
There is an existing sewer pipe underneath the golf course, so we will be constructing a chamber which connects the existing sewer to the new relief sewer. This will all be carried out within the site compound.
To access our site compound, the track that runs adjacent to the 15th fairway has been temporarily widened for our construction vehicles. A banksman will manage vehicle movements through this road to ensure members can still play safely.
The main construction work to establish the site compound began in January 2021. We aim to finish the work and vacate the course by Spring 2022, however, this will all depend on the tunnel boring machine’s progress as it continues its journey to this location.
Newt fencing has been erected around the site compound and will remain in-situ throughout the work. This is to ensure great crested newts and other reptiles can be safely collected and relocated to a safer location during our work.
With the help of our very own trained sniffer dog Freya, prior to arriving on site the totals during the trapping period were 32 great crested newts, nine slow worms, three smooth newts, 11 toads and one frog.
Information on how to safely play golf between the 15th and 17th holes has been shared with members and flyers will also be available at the pro shop.