Four-way temporary traffic lights will be installed at the top of St Mark's Hill in Surbiton as engineers repair a burst water main.
The 6in pipe burst earlier today, causing "significant damage" to the road surface at the crossroads of Ewell Road, Lamberts Road, Surbiton Hill Road and St Mark's Hill.
A Thames Water spokeswoman said the temporary lights may be in place until tomorrow afternoon.
The repair to the pipe itself should be "straightforward", she said, but damage to the road will take longer to fix.
Thames Water said: "We’re sorry to customers affected by our burst pipe. Our engineers are there now and working to shut off the water supply."