Work on a historic bridge in Newport Pagnell has been extended while repair and maintenance works take place.
Milton Keynes City Council has been carrying out repair and maintenance works on Tickford Bridge since July 4th.
The works, which has left the busy road closed for several months, has now been extended for a further 3 weeks.
Due to the bridge being a Grade I Ancient Scheduled Monument, any works require months of planning and government approval.
'We factor in for these checks in the planning stage and allow plenty of time for any adjustments however if unforeseen issues come up, there can be longer delays pushing the completion date back,' Milton Keynes City Council said.
'In August, the Historic England inspector visited the bridge and raised concerns over the painting works resulting in a change to hand preparation only to retain the historic layers of paint as much as possible.
'We were also required to provide detailed documents on our plans and processes for this stage of the works. This additional work and various other tests delayed the painting stage as we were unable to begin without the official approval from Historic England,' the city council continued.
Tickford Bridge, which goes over the River Ouzel in Newport Pagnell is one of the only cast iron bridges in Britain which still carries road traffic, it is also the oldest bridge in Milton Keynes - built in 1810.
In a letter explaining the extension explains that in September, a pigeon nest was discovered while the scaffolding was being erected on the underside of the bridge. The letter states: 'As all active bird nests are protected under the Wildlife & Countryside Act 1981, we had to consult an ecologist who visited the site in early September and found two active nests, one with eggs and one with recently hatched chicks.
'For this reason, a temporary halt to the works had to be called so that a specially designed protective barrier could be installed around the nests. Once the ecologist had confirmed the birds had left the nests in early October, works could restart. With many schemes like this, once the refurbishment works start, unforeseen issues can appear.'
The City Council say that once the defective paint layers were removed, serious structural defects became visible including cracks in the cast iron and the work must be 'carried out with additional safety measures due to the high lead content in the paint'.
Now, the City Council are waiting for approval from Historic England.
'The permit for the bridge works is due to expire on 14 November. Due to the reasons listed above this date is no longer realistic and we will need to extend the permit until 25 November, which has been requested,' they explain.
Despite the extension, Milton Keynes City Council say they are 'confident' that the work will be completed in time for the Christmas Light switch on scheduled for the 26 November.
