Water tankers are being "urgently" deployed to Porirua after a water main burst, and nearby residents are being urged to conserve water. 

Wellington Water posted on Twitter that the burst main on Parumoana St could impact the water for nearby residents for up to five hours – they could have low water pressure, or in some cases, no water at all. 

"We are urgently sending water tankers to the site. One tanker will be stationary outside 25 Awarua St and the other will be roving the area to supply water to any residents as required." 

Ian Dennis, Wellington Water's customer experience manager, told the Herald crews have started to excavate the area for the repair and hope to have it completed by 2pm. 

"This may change once the full extent of the burst is determined." 

People in Titahi Bay are being asked to conserve their water to manage the demand on the network. Wellington Water says this can be done by taking shorter showers and holding off on doing laundry or watering the garden. 

Footage posted to a local community Facebook page showed the flooding in full flow around 7am. 

The video showed much of the car park underwater with water spilling out from under the ground. 

Wellington Water said on social media although crews are on-site, work can't start until traffic management is in place, and further updates will be provided once work has begun. 

The Herald has contacted Wellington Water for further comment. 

- by Vita Molyneux, NZ Herald