Thieves have stolen hundreds of manhole covers to sell as scrap, putting road users at risk and costing councils hundreds of thousands of pounds.
For example, Surrey county council has spent £160,000 so far replacing the covers, which cost up to £400 each.
High scrap metal prices have resulted in an increase in thefts, with over 500 stolen this year in Surrey alone. They are often sold abroad, so that they can't be traced as stolen.
Subsequently concerns have risen that the exposed holes could damage cars that drive over them and cause accidents if drivers try to swerve round them.
As a result, it has been proposed that any new manholes are fitted with a more advanced locking system.