Is Auckland's next water crisis looming?

Monday, 8 July 2019

Aucklanders are being urged to use less water after a very dry start to the year.

OPINION: Auckland has had the driest first half of any year on record, in some rain gauges.

That means less rain than the same period in 1993. Why is that significant?

The 1993 dry spell ran all year, and through the next summer, taking Auckland into its worst-ever water crisis, as storage dams fell to just a few per cent short of a level where serious rationing would start.

The city was gripped as daily data showed the dam levels falling, restrictions and saving measures were unparalleled and some politicians and senior managers' careers were seriously damaged by public anger.

* No change in water consumption despite calls to cut showers

* Auckland's effort to cut water consumption is working

* Watercare announces end of Auckland water-saving campaign**

Then, as the dams drained to just 36 per cent capacity in the autumn of 1994, it rained.

City leaders, and there were a lot of them in pre-amalgamation Auckland, demanded a boost to the city's supply, and a huge pipeline was built to take water from the Waikato River, and feed the city. Problem solved, we all thought.

Auckland's population has risen by 38 per cent since the 1994 crisis, and the once almost-superfluous supply from the pipeline can now meet only 35 per cent of the region's demand, at full stretch.

The rest comes from the same storage lakes that served the city 25 years ago, with some tweaks on how they interconnect, and some extra urban reservoirs.

Last week the storage capacity fell to 59.2 per cent, a quarter less than normal, and the council company Watercare issued a low key warning.

'We want everyone to use water wisely and reduce wastage of this precious resource, this will help our dams to recover over the winter months, ahead of summer 2020,' said Roseline Klein, the head of water value.

Seemingly small things would help, like turning off the tap while you clean your teeth, or cutting shower time by a minute.

So what are the odds of the water shortage getting serious - maybe as bad as 1994's 'one-in-a-100-year-drought?'

'You don't know what you don't know', was the Mayor Phil Goff's most insightful line when I asked after his level of concern, based on what Watercare had told him.

Should Watercare be sounding the alarm more loudly?

'They feel they are setting it at the appropriate level now,' said Goff, who also said he couldn't remember 1993 when I asked for a comparison.

Aucklanders then stepped up to cut use by 23 per cent, as washing a car or watering a garden became socially unacceptable.

It's all down to whether it will rain, when, how hard, and will it fall in the main catchment areas of Waitakere and Hunua.

Climate agency NIWA holds out little hope for July, and the one to watch is a climate model suggesting 'increased wetness' in the North Island in August and September.

Watercare's Klein also pointed to that grey lining in the silver cloud.

Unlike 1993, when part of the problem was failing to sound the alarm early enough, the word at least is already out.

Whether Aucklanders get the low-key message in an otherwise cold and damp winter is questionable.

If the hoped-for September wet spell doesn't hit the catchment areas then things might change. A month out from local body elections.

One well-targeted day of downpours last week added nearly 5 per cent to storage levels, showing how quickly things can change. Or not.

The lesson from 1993-94 for Aucklanders is, start saving seriously and early.

The Waikato pipeline means Auckland may not run out completely, but it won't avert major and compulsory savings, if the weather gods don't play ball.