We're investing £55 million to build a new relief sewer in North Bristol to ensure our sewerage network can cope with ongoing and future development in Bristol and South Gloucestershire.
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, but no one will feel our presence there.
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 tunnel entrance in the hillside below Oasis Academy Bank Leaze began in August 2019. This is due to finish by March 2020, when the tunnel boring machine will begin its journey northwards to construct the main part of relief sewer.
A smaller section of sewer to connect the main tunnel with the existing Bristol network will be constructed behind Saltmarsh Drive, through the playing fields of St Bede’s Catholic College and behind Attwood Drive. Construction of this section will begin in spring 2020 and is expected to finish by 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.
There will be noise disruption while this work is carried out, particularly during periods of piling, but every effort will be made to minimise this and complete the work as quickly as possible.
An additional connecting sewer will be constructed in Henbury through Crow Lane Open Space. The majority of this sewer will be installed using a ‘no-dig’ technique to avoid open trenching.
An access track has been constructed and a series of compounds set up through the northern end of Crow Lane Open Space between Tormarton Crescent and the Hazel Brook river crossing to accommodate this work.
A large compound has also been established off of Henbury Road. New pipework will be laid through our compound at the southern end of Crow Lane Open Space and the grounds of Henbury Court Primary Academy using a traditional trenching technique. Unfortunately, there is insufficient ground depth to use ‘no-dig’ techniques in this location.
This new section of sewer will connect the existing Henbury and Brentry network into the new relief sewer. A deep access shaft will need to be constructed near Tormarton Crescent to make the connection.
This part of the project began in October 2019 and is planned to finish in autumn 2020, however the access track will need to remain in place until autumn 2021 as we will need to return to fit out the deep shaft with mechanical and electrical equipment.
Members of the public will still be able to use Crow Lane Open Space during our work and we will ensure safe crossing points along our temporary access track are provided. The Sustrans cycle route through Crow Lane Open Space will remain open throughout the work. A temporary diversion will be in place when we cross the cycle path to lay the new sewer.
A new manhole chamber and connecting pipe will be needed in Catbrain Hill, so that we can connect the existing Catbrain sewer network to the new relief sewer via a deep shaft in the former Filton Airfield.
The manhole chamber and pipe will be located close to the entrance of the new Strongvox residential development. The pipe will be installed using trenchless techniques to minimise disruption and avoid excavation.
The new manhole chamber will be constructed in the road verge separating Catbrain Hill and Medlar Close. To construct the chamber, it will be necessary to remove 26 metres of the hedge which grows along the verge. The majority of the hedgerow will be replanted once work has been completed. Access will be maintained to properties on Catbrain Hill throughout the work and construction traffic will access the site via the former Filton Airfield.
Hedge removal in Catbrain Hill is planned for January 2020 and will be replanted in November 2020. Construction of the deep shaft in the former Filton Airfield begins in February 2020 and construction of the new chamber and pipe in Catbrain Hill is due to start in April 2020 and finish in July 2020.