Summer weather could have caused a water main to burst, leading water to gush down Queen St in Auckland’s CBD yesterday.

Watercare’s head of water Sharon Danks today said what caused the 80-year-old pipe to burst can’t be pinpointed but said more water mains tended to burst more in summer when the ground dries up and retracts from pipes, causing them to crack or break.

A large amount of water began “leaping from the ground” and pouring down Queen St yesterday afternoon after an underground water main burst.

A video sent to the Herald showed the rupture outside the Queens Court Shopping Centre on the corner of Wakefield St near the Town Hall.

The road had cracked and ruptured in places near where the water was coming from on Queen St.

Images showed the road had cracked and ruptured in places near where the water was coming from.

Danks said crews continue to work reinstating the road and footpath where the burst occurred on the corner of Wakefield and Queen Sts.

A one-way traffic system is expected to remain in place until tomorrow morning.

She said the 250mm cast iron pipe was installed in 1945.

Danks said the incident is unrelated to a $115 million project by Watercare to upgrade wastewater services running through the midtown area of the CBD to reduce wet weather overflows into the Waitematā Harbour and to allow for growth.

Water main burst on Queen St outside the Auckland Town Hall. Photo / David Williams

The burst water main is on the same section of Queen St where a tunnel boring machine is laying a new wastewater pipe from a shaft at the corner of Queen St and Mayoral Drive for the project.

The new pipe will capture wastewater flows from the eastern side of the city to connect with the Ōrākei main sewer, which will undergo relining as part of the project. Two other shafts will be excavated at the corners of Wellesley St and Victoria Sts with Queen St.

The Queen St incident was the second burst water main in Auckland over the past week.

Last Thursday morning, motorists were told to stay away from an entrance to the Sylvia Park Mall after a water main burst on nearby Carbine Rd in Mt Wellington, rupturing the road and flooding vehicle lanes.

Pictures showed the seal surface on two lanes ruptured into a pipe-shaped mound and water rushing out of cracks onto the street.

A burst water pipe last week caused traffic delays at Carbine Rd in Mt Wellington near Sylvia Park mall in Auckland. Photo / Nichola Barnden

Emergency workers were at the scene cordoning off sections of the flooded road while cars cautiously travelled over the disintegrated road surface.

As a result of the incident, about 50 properties experienced low pressure or no water, Watercare said.

The cause of the burst pipe remains unknown, Danks said today.

Two days earlier, a sinkhole formed in the wealthy inner-city suburb of St Marys Bay.

The hole was about 50cm wide, but a a firefighter said there was a larger void of about 2sq m under the surface.

The chasm revealed extensive brickwork beneath the road.

A council spokesperson said repairs began last Friday filling the cavity under the catch pit and are expected to be completed tomorrow.

The council will continue to investigate the cause of the sinkhole, which doesn’t appear to be related to public drainage, the spokesperson said.

The sinkhole in Saint Marys Bay. Photo / Michael Craig

While the cause of the sinkhole remains unclear, large hollows elsewhere in the city in the past two years have been blamed on deteriorating pipes and high rainfall.

In September 2023, a 13m-deep hole on St Georges Bay Rd in Parnell opened to a 2.1m-wide collapsed brick pipe that served Central Auckland and West Auckland.

About 150 litres of sewage a second flowed into the Waitematā Harbour at the time. Calculated over 24 hours, there would be at least 8.64 million litres a day draining to the harbour.

Watercare released findings of a report six months later with the council organisation apologising profusely and promising to work on rebuilding its sewer network.

The report said the condition of the pipe, weakened concrete blocks at the sinkhole’s location, excavation for a power cable nearby and corrosion and erosion led to the chasm opening up.

Another sinkhole on College Hill appeared months earlier in July 2023 when a stormwater pipe cracked and led groundwater to seep in during heavy rain events.

Earlier still, another sinkhole occurred on the same pipe a bit further down College Hill near the corner of Victoria Park during the January 27, 2023 floods. This sinkhole, on a busy intersection, was quickly filled in.