Kennet & Avon Canal Crofton Pumping Station works are to be completed this year.
Our project to replace the pumping system at Crofton, keeping the summit of the Kennet & Avon Canal topped-up with water for boats, towpath users and wildlife, will be completed this winter.
The plan
The works, near Great Bedwyn in Wiltshire, started last month and will continue through to July 2023. Costing £1.8 million, the project will see the 40-year-old pumps, pipes and electrics replaced with a modern, more efficient and reliable system.
To enable the upgrade to take place, part of the closed stretch of canal will be drained so that new pipework, pump and electrics can installed. There will also be works at Wilton Water to improve the flow of water from the reservoir, and the historic water control gates (penstocks) will be restored as a heritage structure.
The work this winter is the second phase of this important project to keep the canal navigable, for the benefit of people and wildlife. Phase one of the works, completed in March 2020, laid new pipes connecting to the existing historic pipeline beneath the canal, and installed new pipework under the railway and up to the canal feeder channel.
Increasing efficiency
Charles Baker, our senior project engineer, explains: "Crofton Top Lock is the highest lock at the head of the eastern descent of the Kennet & Avon Canal. The pumping system at Crofton keeps the canal summit topped up with water, which is vital for boaters and wildlife, as well as the thousands of people who visit the canal towpath each year for the health and wellbeing.
"After 40 years of service, the 1980's electric pumping system has become unreliable and less efficient. With the Kennet & Avon Canal more popular with people and boats than at any time in history, the new pumping system will increase efficiency and the amount of water that can be pumped into the canal."
Towpath and navigation closures
To enable the works to be carried out, a six-mile stretch of the Kennet & Avon Canal, from Lock 52 (Heathy Close Lock) to Lock 65 (Burnt Mill Lock), will close to boats from 7 November 2022 until 3 April 2023. A diversion will also be in place for the half-mile stretch of the towpath that will be closed between Lock 58 and Lock 61 on the Crofton flight.
The navigation will re-open on 3 April, but the towpath will remain closed between Lock 58 and Lock until July 2023. A diversion is in place for the half-mile stretch of the towpath that remains closed. Localised access for boaters will be available for Locks 58 to 60 once the navigation is reopened, but the towpath will remain shut from Lock 60 to 61 and around the edge of Wilton Water.
The construction of a temporary works access track to allow access to the canal and a temporary dam within Wilton Water.
Installing a new inlet structure within Wilton Water to carry water from the reservoir and into the new pumps and pipeline.
Building a new pipeline beneath the canal, carrying water from the reservoir and connecting to the pipeline that were replaced in Phase One of the works. This pipeline takes the water 13 metres up to the canal feeder channel, which starts at the historic Crofton Pumping Station. The historic culvert beneath the canal will remain in place.
Installing two new pumps at the edge of the towpath below Lock 60 to pump water from the reservoir, through the pipework and into the canal feeder channel.
Installing new electrical cables and upgrading the power supply to the new pumps.
Integrating new pump controls within the Trust's national Scada system, to allow automatic operation and remote diagnostic checks, optimising running times and water flows into the canal.
Restoring the historic penstocks (water control gates) at Wilton Water as a heritage structure.
Repairing the brickwork on the weirs within Wilton Water.
Crofton Beam Engineers
The pumps at Crofton supply water from Wilton Reservoir to the Kennet & Avon Canal. They have been powered by electricity since the 1980's, but the pumps in the original pumping station at Crofton were steam powered.
Soon after the canal first opened, the historic Crofton Pumping Station was built in 1807-9 to supply water to the highest point of the Kennet & Avon Canal. The steam powered pumps continued to operate until 1959.
In the 1980's, when the canal was restored, a new pumping station was installed powered by electric pumps. Now owned by the Kennet & Avon Canal Trust, the steam pumps housed in the historic Pumping Station building, continue to be regularly demonstrated to the public by volunteers at open days.
As well as upgrading the pumping system at Crofton, as part of the Canal & River Trust's winter maintenance programme, the following works will be carried out along the closed section of waterway:
Lock 52 (Heathy Lock) the bottom lock gate will be replaced and repairs made to the offside top anchor point, waterway wall at the lock landing and quoin offside;
Lock 55 (Crofton Top Lock) the top lock gate will be refitted to reduce leakage;
Lock 57 (Crofton) the top gates will be repaired;
Lock 60 (Crofton flight) the bottom gate quoin masonry will be repaired;
Lock 61 (Crossing Lock) the top and bottom gates will be replaced, and masonry repairs will be undertaken in the lock chamber;
Lock 64 (Church Lock) the top and bottom gates will be relined; and
Lock 65 (Burnt Mill Lock) the bottom gates will be refitted.
