Motorists are being warned of delays approaching Yaxley due to roadworks.
The works are taking place on the A15 at the junction of Broadway, preventing motorists turning left into Broadway.
Queues have stretched back to Hampton on the approach to Yaxley.
The works appeared yesterday (Tuesday), causing delays during rush hour last night and this morning.
A spokesman for Cambridgeshire County Council said the works were being carried out by Anglian Water, and were scheduled to finish tomorrow (Thursday).
An Anglian Water spokeswoman said: “We had a burst mains water pipe on that junction. We repaired the burst yesterday evening and today our team is reinstating the road.
“To keep our staff safe whilst they completed the repair work we needed to put a diversion in place. The work will be complete and the diversion removed later today - we hope before rush hour this evening. We’re really sorry for any disruption caused to road users.”
Motorists are advised to try and find another route.