Residents have bemoaned "traffic chaos" on a Kings Langley road, with disruption scheduled to continue for the next few days.
Affinity Water is carrying out "essential maintenance" in Watford Road, with temporary traffic lights being put up this morning (October 22).
Residents received a message earlier this week informing them of the work, with the company saying it aims to complete the work "within four working days".
Traffic website One Network says the works will continue until Thursday night (October 24), with delays "possible".
Several residents took to social media this morning after being caught up the congestion, bemoaning the "chaos" the works had caused.
One wrote: "It took me 50 minutes to get the kids to school. We normally walk from Primrose Hill Park but there wasn't time for that. The High Street was absolutely terrible."
Another added: "I've just come back from being stuck in it. Impossible to get anywhere without being stuck in the High Street for ages."
A third sarcastically labelled the situation "a joy", describing her experience as "absolute mayhem".
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