Work underway on a Historic England-funded project to restore 200-year-old side ponds at the Hanwell Flight of Locks in West London. The initiative follows a year of navigation closures caused by drought and climate change and focuses on locks 94 and 95. The scheme is supported by Historic England, the Inland Waterways Association and the Canal & River Trust.
Water-saving engineering at Hanwell
EACH movement of boats through locks uses thousands of litres of water, which must be replenished from reservoirs, river flows, boreholes or other sources. Georgian engineers understood this problem, and, in 1815, some 20 years after the flight of six locks at Hanwell, West London, was built as part of the then Grand Junction Canal between London and Birmingham, side ponds were constructed at each lock.
These meant that when the lock chamber emptied to lower a boat down to the next level of the flight, instead of the water being lost to the lower canal pound, paddles connecting the lock to the side pond were opened and it was ‘put aside’ and stored to assist in refilling the lock.
Decline and disuse over two centuries
But over the course of two centuries, these ingeniously frugal – but ultimately non-essential – features fell into disuse and disrepair, in a world where the overuse of resources became commonplace.
In 1975, the Hanwell flight of locks and brick boundary wall of St Bernard’s Hospital were listed as a Scheduled Monument, with the then Royal Commission on the Historical Monuments of England noting the presence of side ponds at every lock from 92 to 97 in the citation.
Drought, restrictions and renewed relevance
Fast-forward to 2025 and such careful conservation of water supply has never been more relevant, with the Canal & River Trust forced to introduce a number of navigation restrictions during the summer to prevent the 2000 miles of waterways the charity cares for from running dry.
Funding and scope of restoration works
The Hanwell Flight of Locks repair and restoration project is being funded by Historic England’s regional Heritage At Risk repair grant and will clear, stabilise, and restore the derelict side ponds at locks 94 and 95. While this initiative itself – with a £180,000 grant from Historic England, £5000 from the Inland Waterways Association (IWA) and the remaining contribution from the trust – is not intended to restore the side ponds at Hanwell to operational use, it could inform any such project in the future and point the way towards how inland navigations might make better use of increasingly precious water resources.
Canal camp and volunteer training
The programme of conservation brickwork repairs will include a week-long canal camp with the IWA’s Waterway Recovery Group and training sessions with the trust’s volunteers led by contracted conservation brickwork specialists in spring and early summer.
Wider community and environmental aims
The CRT said the project will create a more beautiful space, offering improved physical and mental wellbeing, educational opportunities, and local pride. It builds on the Southall Wellbeing Way and complements the proposed Ealing Regional Park, embedding the historic waterway within a wider green infrastructure network. Ultimately, the project will leave a lasting legacy of environmental stewardship, civic engagement, and heritage conservation.
Heritage advisor comment
Trust heritage advisor Phil Emery said: “It’s hard to overstate the historical importance of these side ponds, situated on a stretch of what is now the Grand Union Canal that has been immortalised by the painter JMW Turner, and which offer a direct connection to the engineering prowess and foresight of the Georgian canal builders.
“The clearance of vegetation and silt from the ponds at locks 94 and 95 under archaeological supervision will give a better idea of the scale of any structural damage and inform the later stages of the project.”
