Commemorative Oxford mosaic preserved during water leak repairs

A mosaic celebrating Oxford’s twinship with the Dutch city of Leiden was preserved during recent work to fix a water pipe leaking directly beneath it.

The commemorative artwork close to the Town Hall in Blue Boar Street was carefully lifted from the pavement to allow Thames Water engineers to dig down and repair a 4-inch wide cast-iron pipe without damaging any of the colourful tiles. 

The mosaic, which measures 1.6 metres across and weighs around 600kg, is believed to have been installed in 1996 and was moved in one piece by specialist contractors Cliveden Conservation Ltd using heavy lifting equipment.

Tom Hutchinson, regional water networks manager for Thames Water, said: “Reducing leakage is a top priority for us, and this includes fixing pipes in hard to reach and unusual places. This was definitely one of the more interesting and high-pressured jobs I have experienced in my years at Thames Water.

“It’s really important we preserve any landmarks and heritage sites while doing our job, and so once we had detected the leak deep under the mosaic we had to make sure it was removed and replaced with the care and precision needed. It was a great team effort and to see it now you’d never even know anyone had been digging below.”

Thames Water has committed to reducing leaks from its pipes by 20 per cent by 2025 and last year fixed more than 4,000 leaks in Oxfordshire. Since 2015 the company has invested £7 million upgrading 30km of pipes in the county – enough to go around Oxford’s famous Ring Road one and quarter times. The hidden leak was detected using modern technology which recognises changes in how water flows through pipes, with abnormalities in sound or speed of flow indicating a possible leak.

Liden was the first city to be twinned with Oxford, with the relationship formed immediately after the end of the Second World War. It is home to the oldest university in the Netherlands and, like Oxford, is renowned for its bookshops and cycling student population. An area of the Westgate Shopping Centre is named Liden Square in honour of the twin city. Oxford is also twinned with seven other cities including Bonn in Germany, Ramallah in Jerusalem and Padua in Italy. 

Councillor Mary Clarkson, Oxford City Council’s Cabinet Member for the City Centre, Covered Market and Culture said: “March 2021 marks the 75th anniversary of Oxford twinning with Leiden and we are marking the anniversary with online events that include a collection of photos that can be viewed on the Museum of Oxford’s website.

“Leiden was Oxford’s first city twin link. Twinning started immediately after the Second World War as part of a movement to foster friendship among nation and Oxford is now twinned with eight cities worldwide. Like Oxford, Leiden is home to a famous and ancient university and so it made a fitting choice to be our first twin town. 

“I want to thank Thames Water for its careful handling of this beautiful and historic mosaic during the recent repair work, and I hope visitors to the city will seek it out and enjoy it for many years to come.” 

Thames Water has recently employed a new archaeologist to ensure its ongoing work to upgrade its water pipes and sewers doesn’t impact any archaeologically important sites. The company’s engineers regularly unearth fascinating finds under streets and fields, including over two dozen 3,000-year-old human remains while protecting a rare chalk stream in Oxfordshire in 2019.