Another large organisation has been dobbed in for having sprinklers running over the weekend despite Watercare telling Aucklanders to urgently curb how much water they use just days earlier.

Herald readers spotted the sprinkler outside Auckland University's Grafton campus watering the grass on Monday morning, despite rain also falling from the skies.

On Friday, Watercare urged the public to stop watering the garden, washing their cars and to have shorter showers after storm damage to the Ardmore treatment plant meant it was treating 50 per cent less water than usual.

The calls to save water or be prepared to boil it were renewed yesterday as Auckland failed to save enough water on Monday using 19 million more litres than its 400 million litre daily target.


But a spokesman for the University of Auckland said its 40 automated sprinkler systems were shut down progressively from largest to smallest because a contractor was needed on site to manually override each system.

The grass area at the Faculty of Medical and Health Science in Grafton was the smallest area so was the last to have its sprinklers turned off on Monday afternoon.

Meanwhile the university said it had taken a number of significant actions to reduce water use across all its campuses, which included suspending its window and building washing programme.

Auckland Council had a similar situation at the weekend with its development arm Panuku still running sprinklers in Wynyard Quarter on Saturday.

The sprinklers were overlooked because they were on an automated timer, but were turned off by an official running the system urgently once it was pointed out.

The council now has all sprinklers and fountains switched off and Auckland Transport has also ordered that water blasting at its bus shelters, train stations and platforms only be carried out if absolutely necessary.

Watercare said it had not received any calls from people dobbing in their neighbours and that the 30 commercial customers who were its biggest users had also got onboard and were saving water.

Z and Caltex petrol stations have closed their car washes in Auckland in a bid to conserve water and Mobil is developing a plan.

The service station chain stopped operating more than 20 of its car washes in the Auckland region from the end of last week, and had also asked its subsidiary Caltex, whose stations are independently owned, to follow suit.

Z senior communications advisor Jeremy Clarke said the company wanted to play its part in reducing water demand despite a portion of the water in its car washes being recycled.

"While this reduces consumption we believe that ceasing operations makes sense to maximise the water savings possible."

BP, however, felt re-using some of the water at its car washes at company-owned sites was enough for now.

BP spokeswoman Shelley Brady said it would work with council if it was told further action was required.

Mobil Oil New Zealand said it was in the process of developing a plan to reduce water use at its Auckland service stations which could include temporary changes to car wash operations.

Sky City also estimated it had reduced water usage by 10 per cent by adjusting a valve which reduced the water flow into its 635 hotel rooms across both hotels.

Meanwhile Auckland Council has also revealed the culvert at the centre of serious flooding in New Lynn was on a "hotspot list" and inspected before the weekend. The council believes a significant blockage caused the culvert to flood.

The revelation comes after mayor Phil Goff ordered the council to look into the failure of the New Lynn culvert and the Ardmore water treatment plant after last week's heavy rain.

The council has been slow to improve the city's stormwater infrastructure, which a 2011 council report said needed $9.9 billion to fix over the next 50 years. Yet in the past six years, it spent only $640 million on growth and renewals for stormwater.