Analysis - News today that Aucklanders probably won't have to boil their drinking water was a rare clear message after a week when media management seemed to trump a good flow of information, writes Todd Niall.

Photo: Supplied / Watercare

Those following the daily scorecard from the council-owned Watercare over the past week could have been forgiven for thinking the day Auckland would have to boil its water was coming.

Today Watercare gathered the media to say the risk was all but over - good water savings, and incrementally rising production had seen off the risk, which began after last week's heavy rain clogged the city's main treatment plant at Ardmore.

But how well did Watercare communicate what was going on as crisis threatened and then receded?

From last Thursday's announcement that silt contamination had shut down and then impaired the treatment station from the largest of Auckland's five major water sources, the message from Watercare was absolutely consistent: Aucklanders needed to cut daily consumption from around 450 million litres a day, to 400 a day. That's equivalent to 20 litres, or two buckets per person.

Photo: Supplied / Watercare

Shortly before its first major media conference last Friday, it hired PR agency SenateSHJ, for an undisclosed sum, to help hammer home the message.

Why spend public money on a PR agency, rather than call on the help of its parent Auckland Council, which is geared to up manage Civil Defence and public emergencies?

"Our core in-house communications team has only five people. Any organisation of Watercare's size has the need for an external communications agency from time to time," it explained in a statement to RNZ.

"In a critical situation such as this, it's essential that we bring in additional support to ensure we can distribute our message quickly and effectively to 1.4 million Aucklanders."

That message was 20 litres per person, 400 million litres a day.

Aucklanders took up the challenge, helped by it being a weekend of very heavy rain (that likely stopped people watering gardens, washing cars and chucking through loads of washing), and put in two days below the 400 target. "Well done everyone", said Watercare in its daily update.

But on Tuesday the message unravelled.

Sitting in front of city councillors, Watercare's chief executive, Raveen Jaduram, revealed the previous day had spiked, and water use had risen to 419m litres, 19m litres above the target.

This, he told councillors, was "a good effort".

At a media briefing shortly afterwards, I asked him how missing the target could be good, and weren't they blurring their own message.

"Four hundred is still the target, the message will get blurred depending on how you get it out on our behalf," he said.

But as he explained how the water supply system works, the 400 number on its own, seemed largely irrelevant.

Photo: Watercare

"While we are asking for daily savings, and I'm saying we re-set the target every day, the key component is how we are supplying the water to our reservoirs," said Mr Jaduram.

Auckland has 72 reservoirs of treated water on higher ground around the region, providing a short-term additional buffer of water.

They fall to around 80 percent full during peak periods as Aucklanders use more water than is coming out of the main supply sources, and are then topped up to around 95 percent overnight, restoring the buffer for the next day.

"We know that if customer demand is not going to be shooting up to 460 (million litres a day) which is what it was before the rain storms, we'll be able to fill them up," Mr Jaduram told media.

"So even though it was 419 (on Monday) and we wanted it to be below 400, we still managed to fill up the reservoirs."

Watercare continued to remind Aucklanders of the 400 target for the next three days, as consumption remained stubbornly above it.

"Auckland is edging closer to having to boil its water" a commercial radio network proclaimed on Wednesday.

I asked Watercare for a daily update on reservoir replenishing, to help fill-out the scenario explained by their CEO.

"Reporting on treated water storage levels is not material to the current constraint on water production at the Ardmore Water Treatment Plant," it replied in a statement.

It didn't provide a requested update on how production from the impaired Ardmore Treatment Station was faring

One week into its messaging campaign, Watercare dropped the 400 figure from its daily media update, simply noting that Wednesday's 415m litre consumption compared well with the 444m used a fortnight earlier.

Believable and trustworthy messaging in key public agencies is critical.

On Tuesday, Watercare's chief executive told it like it was: "I'm just being transparent and honest. I'm not an expert in the messaging and I'm not trying to spin it, I'm just being very honest."

Today, eight days after urgently seeking savings, Watercare confirmed the risk was fading due to savings which took the week's average consumption down to 404 million litres a day. Above the target, but enough, with production now 10 per cent higher .

The Admore Treatment Plant had lifted production from 50 per cent of normal levels to 55 per cent - the figure not provided the previous afternoon.

The risk of a boil water notice was no longer imminent, but the achieved savings needed to continue while the Hunua lakes and the Ardmore Treatment Station continued.

Mr Jaduram apologised for the failure to provide information, all of which was available in it's operations room.