North Marine Road is closed after a sewer collapsed.
There is no access from the Castle Road roundabout.
A Yorkshire Water spokesman told The Scarborough News: "Customers will temporarily be unable to turn up North Marine Drive at the roundabout junction with Castle Road as we carry out emergency repairs to a blocked sewer.
"Diversions will be in place, and this work is only affecting one lane, so traffic approaching the roundabout from North Marine Road will be able to pass as normal.
"We're working hard to get the sewer fixed and cleared as quickly as possible and we hope to have the road back to normal by the end of the week.
"We're sorry if this causes any problems to customers journeys."