People needing "blue light" emergency services will be at risk if the historic bridge between Huntingdon and Godmanchester is damaged by errant HGV drivers, a councillor has warned.Godmanchester district councillor Sarah Conboy fears that the medieval bridge would have to close to traffic if its fragile parapet was smashed by lorries breaking a 7.5 tonne weight limit designed to protect the stone bridge, a Grade I listed structure.The number of HGVs crossing the bridge illegally has shot up since a new section of the A14 opened last month and two have been ticketed by police. It is thought drivers are being confused by signs on the new road and a lack of satnav updates - leaving them in a position where they have no choice but to travel over the bridge. Cllr Conboy, leader of the council's Liberal Democrat group, said: "There is a problem and it is being raised every day. The danger is that if the bridge was damaged it may have to close which would mean long detours for the blue light services which could put people at risk." Weight limits were imposed to protect the bridge, which is also a Scheduled Ancient Monument, as well as the town from heavy goods vehicles. Until the original A14 flyover was built in the 1970s traffic from Cambridge to Peterborough passed over the bridge. A spokesman for Highways England, which is responsible for the £1.5 billion A14 upgrade, said: "The new A14 is by far a better route for the vast majority of HGVs driving through the area and we share residents' frustrations that some lorries are using the old town bridge instead. "We're doing everything we can to encourage drivers onto the new road and we shared information with all major mapping and online map companies before the new bypass opened last year." The spokesman added: "We have also put up additional electronic signage at the Godmanchester junction advising drivers that access on to the A14 westbound is via the A1198. "Upgrading the A14 is a massive job and we appreciate that living near a busy construction site isn't easy. One of our main priorities throughout the process has been to ensure disruption to local communities is kept to a minimum."