Hertfordshire Council has closed St Johns Road, between Woodford Road and Clarendon Road this morning - and say it could remain shut for up to four days.
The council added: "It is possible that by exposing the hole and then subsequently back-filling, this will cure the problem. A small section will be resurfaced upon completion.
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The moment a lorry driver stopped traffic to let out the apparent migrants from the back of his vehicle was filmed by another driver