Our engineers responded to reports of an issue with the Sea Lock Gate at the entrance to the Ribble Link. This lock gate ensures an adequate depth of water along the length of the Ribble Link, important for boats navigating to and from the Lancaster Canal.
Challenges of tidal river maintenance
Our team discovered that the seal around the gate, which keeps the lock watertight, requires maintenance as too much water is being lost to maintain levels necessary for navigation. To carry out the repair we are facing the challenges of working on a tidal river with a short window each day to carry out work, and the complexities of a lock gate designed to withstand tidal conditions.
To replace the seals, the caisson in which the gate sits needs to be sealed off. Usually stop planks would be used to prevent water getting in, however on the Ribble Link the caisson is flooded twice daily, submerging the lock and making any form of maintenance impossible. To remove the gate to conduct repairs, either a temporary abutment must be created around the caisson to prevent tidal waters entering, or work must be conducted in short windows at low tides. This second option will require high-capacity pumps to remove the water rapidly, giving at least two to three hours of working time every day.
Comprehensive gate Ooverhaul
On Thursday 18 July, our engineers will meet with contractors on site to plan the works. Planning and developing a solution is likely to take several weeks, and we will provide an update when confirmed.
Following preliminary work to reduce leaks through the seal, the gate will be lifted out and sent away for repair at our workshop. As well as repairing the seal, the gate will get a full overhaul, with the hydraulic cylinder, pivot pins and bearings also getting attention.
We are contacting all boaters who have booked to use the Ribble Link.
Getting everything back in working order
Darren Thomas, our senior engineer, said: “As the link to the national waterways network, it’s important that we get everything back in full working order as soon as possible. Working in tidal areas adds complexity, with less time to carry out work as the water levels fluctuate, and we’re spending time carefully planning this intricate repair job. While the gate is out of the water, we’re taking the opportunity to give it a thorough upgrade so it can continue to withstand the challenging conditions.
“We thank boaters for their patience while we carry out this work to ensure the Ribble Link is safe and look forward to reopening so boaters can navigate to and from the farthest reaches of our canal network.”
Background on the Ribble Link
The Ribble Link connects the Lancaster Canal to the rest of the national waterway network. The Link runs around the outskirts of Preston and flows into the River Ribble, which connects with the Leeds & Liverpool Canal. The idea for the Link dates back over 200 years but the proposals were expensive and a tramroad was built instead. The dream of making a navigable link between the Lancaster Canal and the rest of the inland waterway network never fully died and, after receiving funding from the Millenium Commission, the Link opened to navigation in July 2002.
Boaters can contact the our regional team on 03030 404040 selecting North West.
