Central Wellington asked only to flush when 'essential' after wastewater pipe bursts

People living in central Wellington are being asked to flush their toilets only when "essential" as workers scramble to fix a burst wastewater pipe.

On Tuesday Wellington Water tweeted a map of streets which should only be flushing when absolutely necessary - the affected areas span the majority of the CBD from Taranaki St to Featherston Quay.

The wastewater pipe causing all the commotion burst on Monday afternoon at the intersection of Victoria St and Mercer St.

It sent wastewater spewing onto the road and towards the harbour. Residents were told to stay out of Whairepo Lagoon as a precaution.

Wellington Water said sucker trucks were able to keep up with demand overnight, meaning no sewage has made it into the harbour.

"There are additional sucker trucks on site to help with peak demand to prevent overflows into the harbour."

In December 2020 a mayoral taskforce into the city's water woes revealed 60 percent of it's pipelines will need to be replaced within 30 years.

Thirty percent of the capital's drinking water assets and 20 percent of its wastewater networks have already passed their use-by dates.