It is thought to be the biggest fine ever secured by Lancashire County Council, which monitors safety obligations on firms carrying out street works.
Virgin Media Limited began carrying out superfast broadband related works in Lancashire in September after meetings with highways officers to ensure roads were safe to use while works were in progress.
But Lancaster Magistrates’ Court heard inspections revealed breaches at some locations and a warning letter was sent to the firm.
The bench was told in December officers found works on Edenmount Way in Carnforth in a “dangerous state” for traffic and pedestrians.
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The works had been set up on a blind bend using the “give and take” system of traffic control, which assumes traffic will give way to oncoming traffic. It cannot be used safely on a blind bend as drivers can’t see to the end of the roadworks.
Officers said workers showed a “blatant disregard for their own safety and the safety of others” and practices presented a number of “accidents waiting to happen”.
The magistrates took into account Virgin’s similar convictions.
Prosceutor Nick McNamara said, “Ensuring our highways are safe for pedestrians and other road users is our paramount concern and is particularly important for people with mobility issues, for children and those with push chairs. This case highlights the severe penalties for contractors who fail to put safety first.”