Drivers have been caught on camera mounting the pavement to bypass roadworks, potentially putting pedestrians at risk.
Engineers from Thames Water repaired a leaking water pipe in Vicarage Farm Road, Heston, last night and closed the road to allow the surface to set.
But one resident photographed motorists - including one lorry driver - driving up on to the pavement to circumvent the road closure.
Martyn Hall tweeted Hounslow Council, Hounslow Police and Thames Water to alert them to the potential danger.
Growing exasperated by the lack of response, he tweeted 'maybe you'll take notice only when a pedestrian gets mowed down by a van?' before adding '1hr gone, any response to this? It's getting dark and dangerous!'
Hounslow Police tweeted to say they had attended the scene in response to calls, while Hounslow Council responded to say its contractor Hounslow Highways was 'investigating the traffic management issues'.
A Thames Water spokesman claimed a member of public had moved the barriers to allow cars to pass, and urged drivers to stop using the pavement.
"We have a zero compromise approach to health and safety, and would ask drivers to stop using the path and find another route," he said.
"What they are doing is clearly very dangerous for pedestrians and could result in a serious injury, which is completely avoidable by following the rules."
However, a spokesman for council contractor Hounslow Highways claimed Thames Water had failed to place ‘road closed’ signs at the entrance to the road, as requested by the council.
“The road is closed, with a diversion route in place. However, it appears ‘Road Closed’ signs were not placed out,” a spokesman for Hounslow Highways, which is responsible for maintaining the borough’s streets on behalf of the council, said on Wednesday (March 26).
“Hounslow Highways instructed Thames Water to place the ‘Road Closed’ signs out and is monitoring the site to ensure the safety of road users and pedestrians. Work is expected to be completed today (Wednesday, March 26).”
Hounslow Police and Hounslow Highways both said on Twitter they had attended the road to investigate the situation following Mr Hall’s complaints.