The situation
Across the South West our sewerage system is showing its age and is in need of upgrading. This is especially true of the sewer running from the pumping station in Penryn. Following a number of bursts in the past few years, it's reached the end of it's working life and needs replacing.
Recent upgrades to the pumping station and this replacement of the main will add resilience to the network and reduce the risk of pollution.
The plan for Penryn
The replacement of the sewer will happen in stages, and we'll use a combination of techniques - open cut excavation, and lining.
There will be traffic lights on Commercial Road and Eastwood Road for a time to ensure the safety of the public and our teams, but all businesses will remain open and accessible during the works. We apologise for the delays this will cause, and advise that if you normally use this route for Falmouth, please use the bypass instead during this time.
Stage 1: Commercial Road to Falmouth Road
New mains installation, completed between January and February 2024.
Stage 2: Eastwood Road at junction of Falmouth Road
New mains installation, completed in March 2024.
Update: August 2024
New mains have now been successfully installed, the next stage is to return to site to re-line the sewer over the bridge and make final connections to the pumping station.
Due to highway access, we can no longer return in September 2024 and works have been moved to May 2025. Further traffic management will be required for the lining works to be completed next year.
What you'll see
For the majority of this project, we'll be using open cut excavation - which means we'll dig a trench down to the pipe, cut the pipe out and replace that section. This type of work is noisy and produces dust. We'll be using pneumatic drills, diggers and other noisy equipment to complete the replacement.
In other sections, we'll be using lining, which is when a repair happens inside the pipe itself. Unfortunately, due to the fragility of the sewer, we are unable to use this technique for the full length of pipe.
1. Preparation
- Set up traffic management and safety barriers
- Survey the site and mark up the existing services – we do not want to damage other utilities!
2. Digging down
We excavate down to the correct depth, creating a trench for the new pipe. We use diggers for most of the work, but areas around other services have to be dug out by hand to avoid damage.
3. Installing the pipe
- The new pipe is installed on suitable bedding to protect it
- It is then pressure tested to ensure it doesn't leak
4. Introduce flow into sewer
The new pipe is connected into the network and the sewer is brought into service.
5. Restore the working area
We backfill the trench with stone, restore the road surface and repaint any road markings before clearing the site and then the road is opened again as normal.