Vandals are being blamed for the flooding of an underpass which left students stranded while trying to get to lessons at University Academy Holbeach.
The chaos arose on Wednesday morning when a pump controlling the flow of water was broken, leaving pools of water in the underpass below the A17, connecting Penny Hill Road and Park Road, Holbeach.
County highways engineers put up signage warning people not to use the underpass as police directed students and other pedestrians across the A17 itself.
Julie Winterton of Toll’s Lane, Holbeach, said: “My son walked to the roundabout near Boston Road North to cross over, which wasn’t exactly safe, and he told me that a lot of the schoolchildren were crossing over on the A17 itself.
“It’s so dangerous to cross the road there, especially as there is no safe turning lane at both Penny Hill Road and Park Road junctions.”
University Academy Holbeach principal Steve Baragwanath said: “I believe the underpass has to be pumped dry after heavy rainfall due to the high water table, so it wouldn’t be apparent that any damage has occurred until the pump is required after inclement weather.
“Students didn’t report any difficulties to staff in school on Thursday and they were able to return home safely using the underpass.
A spokesman for Lincolnshire County Council highways and transportation department said: “The flooding was caused when a switch on the pump directing the water flow was broken.
“Our highways division and structures teams were aware of the matter and are currently awaiting a report on the damage.
“The police are also aware as it was an act of vandalism.”