The mayor of Porirua, Nick Leggett, has asked police to cordon off a flooded part of the town's train station after a video of young people diving into the dirty water was posted on Facebook.
Heavy rain in the area caused water to pool up around the entrance to thesubway tunnel.
He wrote on his social media page: "I posted a video before of a teenager jumping into the subway full of water at the Porirua Train Station. The video had gone viral and I thought it was a harmless bit of fun.
"However, I've since seen more kids do it and I realise there is real risk in this activity so I've asked the police to go and patrol the area to make sure nobody else is doing the same thing."
