Work could continue until the early hours on the County Hospital's new multi-storey car park – for up to a month.

The extra working hours, up to 1am, have been requested as the operation gets underway to pour concrete to form the decking on what is now mainly a steel-framed structure.

Town councillors were told that the change of working hours has been requested from this week until March 7. It will cover Monday to Saturday morning each week.

Homes in Cornwall Road and Damers Road are nearest to the structure although building work is also visible, and audible, in Alexandra and Edward Road along with Bridport Road and Great Western Road.

Dorchester councillor Les Fry, who visited the site last week, said the company had no option but to pour concrete and then shape and compress it and let it cure within a set time frame.

"It's unfortunate, but there really is no other option" he said.

The company behind the project, Wilmott Dixon, said it was not their intention to be working any later than they needed to, but required the variation in the original planning consent, which limits working hours on the site, incase the extra time was needed.

It said in a statement requesting the change in working hours that will do all that it can to ensure than night time noise it kept to a minimum.

Future development on the Dorset County Hospital site will increase the need for extra parking.

By 2026 patient numbers to the hospital are expected to be up by 22 per cent on the 2015 figure. The hospital currently employs around 3,500 staff and contributes an estimated £169million a year to the local economy. A&E demand alone is expected to rise from 48,000 patients to over 60,000 a year. It was designed for 22,000 a year when it opened.