People are trapped in their houses after a burst water main flooded London Road in Fletton.
Elderly residents are unable to get out of their properties after their gardens were flooded.
London Road Dental Practice has also been affected with patients rung to pre-warn them about the difficulties of getting in and out. The practice, which remains open, said it had called Anglian Water at around 12.30pm but nobody had yet arrived.
The burst water main is near the cul-de-sac of Charnwood Close, which has been flooded as a result.
Cambridgeshire police said there is heavy congestion in London Road as a result of the burst water main.
An Anglian Water spokesperson said: “Our teams are currently working to repair a burst water main on London Road in Peterborough. No homes are off water, but unfortunately a small number of nearby garages and driveways have been flooded.
"We’re really sorry for any inconvenience this has caused - our teams are already on site helping the residents that have been affected and a clean-up will be underway shortly. We know how upsetting flooding can be and we’ll foot the bill for any damage caused and work to get things back to normal as quickly as possible.
"Two-way traffic lights are currently in place to allow our teams to make the necessary repairs. We anticipate the repair to the pipe to be completed tonight with work to continue over the next few days to make the necessary repairs to the road surface. We’d like to thank local residents for their patience while we complete this vital work.”