Footage shows the moment the system activated after being bumped by the truck, sending water gushing onto the road below the airport tarmac.
Drivers in a busy Sydney tunnel have witnessed a spray after a truck hit the overhead sprinklers this morning.
Footage shows the moment Sydney's Airport M5 tunnel's sprinkler system was activated after being bumped by the truck, sending water pouring onto the road below the airport tarmac.
Traffic conditions returned to normal shortly after the incident.
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Maintenance crews will now repair the damage outside of peak travel times.
A Transport for NSW spokesperson said repairs will have to take place outside of busy peak periods.
"Transport for NSW is advising motorists that all southbound lanes of General Holmes Drive at Mascot, including within the Airport Tunnel, are now open following an earlier incident involving the activation of the tunnel's overhead sprinkler system," the spokesperson said.
"The incident occurred about 5.15am this morning when a truck travelling in lane 1 struck multiple overhead sprinkler heads, causing the system to activate and resulting in the temporary closure of one southbound lane.
"Emergency services and Transport for NSW maintenance crews attended the scene promptly to assess and manage the situation.
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"All southbound lanes have since been safely re-opened, with no delays currently being experienced by motorists. The driver of the vehicle is assisting authorities.
"As a precautionary measure, the southbound sprinkler system within the tunnel has been isolated following the damage to infrastructure.
"Fire and Rescue NSW has been notified, and appropriate safety protocols have been implemented.
"Maintenance crews will undertake repair work to replace the damaged sprinkler heads outside of peak travel times, with works scheduled to occur tonight following further assessment.
"Transport for NSW thanks motorists for their patience and cooperation while crews responded to the incident and restored normal traffic conditions. Motorists are encouraged to continue to check Live Traffic for the latest updates."
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