Water-conscious Aucklanders have been keeping a close eye on the neighbours, with more than 100 tip-offs in the two days since restrictions came into force.

Yet despite a small drop in usage, storage dam levels continue to fall following a dry weekend for the country's largest city and no rain forecast all week.

Water supplier Watercare said the weekend's usage was down to 413 million litres a day (MLD), 8MLD less than the previous weekend's average.

"These are promising results which indicate Aucklanders are listening and, in the most part, resisting the urge to wash their cars and water their gardens on a dry weekend," a spokeswoman said.

After the driest four months of a year in Auckland's history, dam levels are sitting at 43.9 per cent - compared with a historical average for this time of year of 76.7 per cent.

Restrictions which came into effect on Saturday for the first time since 1994, ban residents from washing cars or watering gardens with outdoor hoses.

Watercare received 120 tip-offs about breaches of restrictions over the weekend, but was taking an "education-first approach" at this stage, and no fines had been issued, the spokeswoman said.

"Our team is calling the commercial customers and emailing residential customers to ensure they are aware of the restrictions."

Rogue water users can be hit with fines up to $20,000.

Watercare had earlier asked breaches to be reported or for residents to have a friendly conversation with anybody seen flouting the restrictions to remind them of the shortage of the precious resource.

People can wash their car or water their garden as long as they use a bucket or watering can rather than a hose, Watercare said.

Hoses and water blasters are banned for home or business use unless it is for a health, safety, emergency or biosecurity reason.

Affected businesses, including those in the exterior cleaning industry, have complained the restrictions are discriminatory towards them.

Troy Hillard, managing director of Wash Rite, which has seven franchises in Auckland, said the ban on the use of hoses and water blasters could cut their revenue by 70 per cent, just as they limp out of Covid-19 impacts.

Several other businesses have contacted the Herald stating the restrictions could lead to job losses.

Watercare had offered to support businesses with tanks of non-potable water to be used in all water-blasting and cleaning work, and said it would set up stations for collection in Onehunga, Penrose and Albany.

But in an email sent to businesses on Friday it announced although they'd all be open Saturday, from Monday only the Penrose station would be operating.

An Auckland Council spokeswoman said it was seeking to open more distribution sites by the end of this week.

The operation on Saturday "went smoothly" with more than 16,000 litres supplied, she said.

Meanwhile, Watercare is working to increase its capacity at the Waikato River Water Treatment Plant to take an additional 25MLD. Work is expected to be completed by August.

Watercare currently draws 150MLD from the Waikato River, which makes up just over a third of the region's daily usage.

To address the short-term shortage, Watercare was also getting Hays Creek Dam in Papakura running again, and re-establishing a mobile treatment plant at a bore in Pukekohe.

Auckland's council-owned and operated swimming pools are remaining closed due to the water restrictions.

Auckland's water shortage

• Stage 1 water restrictions will be in force from May 16 and prohibit the residential use of outdoor hoses and water blasters unless for a health, safety, emergency or biosecurity reason.
• Under stage 1 commercial car washes are also banned unless they use recycled water; and watering of sports fields, plants or paddocks is restricted to those with an irrigation system fitted with soil moisture or rain sensors.
• Watercare further advises residents to keep showers short - four minutes or less, and only run the dishwasher or washing machine when they're full. No restrictions apply to hygiene measures, and people should continue regularly washing their hands consistent with Covid-19 messaging.