Water use drops, but no rain in sight; Fran asks us to keep saving

Press Release – Wellington Regional Council


Daily target water use (maximum) = 130 million litres (ML)
Today’s water use = 131ML
Change from Wednesday = lower by 6ML
Water use dropped back today to just above the target maximum daily water use. River flow rates are below long-term March averages again and continuing to drop.

The 14-day weather outlook continues to show no rain and mainly fine weather for the next 10 days at least. This outlook raises the prospect of our supply rivers returning to pre-rain low levels during this period and the Hutt aquifer or lakes being drawn down again – if water use doesn’t remain low. We need to maintain the level of water use below 130ML per day. Lower demand helps to preserve our water reserves longer.

Today’s water supply came from:
Rivers: 95ML
Hutt aquifer: 33ML
Storage: decreased by 3ML (within the Regional Council’s distribution network reservoirs)
Storage in Lake 2 was increased by 65ML

River flow rates continue to fall after the recent rain. We remain uncertain how rapidly river flows will return to pre-rain levels and will continue to monitor this critical variable.

Lake 2 is now 100% full.

The outdoor water use ban remains active.


Press Release – Greater Wellington Regional Council
Water use in Wellington yesterday jumped up despite a promising effort earlier in the week. No rain is forecast for the next ten days so Greater Wellington Regional Council is urging people to keep up their water saving efforts. The total amount of water supplied by the Regional Council yesterday was 137 million litres (ML). This is 7ML above the target of 130 million litres (ML) per day – a figure that would extend our emergency storage in another spell of dry weather.

Greater Wellington Regional Council Chair Fran Wilde is calling on households and businesses to continue the water saving efforts which saw Monday taking the record for the second-lowest daily demand since records began in 1997.

“Yesterday’s numbers are pretty disappointing. These figures certainly take the shine off the excellent effort we saw earlier in the week,” says Chair Wilde. “The rain has not made the situation go away – we still need to carry on with our water-saving efforts. Every litre we save extends the amount of time that our reserves will last if we get another dry spell – so we can’t afford sit back and relax.

“We know Wellingtonians can do it – the figures we’ve seen in the last few days are proof of that – so let’s just carry on with the good work for a bit longer.”

No rain is forecast for the next ten days and this period of dry weather could see river levels quickly dropping back to their pre-rain levels. This means that there will be less water available to take from rivers, so water will once again have to be supplemented from the Lower Hutt aquifer, and the water storage lakes in increasing volumes.

“Depending on what happens with river levels, another long period of dry weather could see us back in the position we were in a couple of weeks ago – rivers that are low and dropping, and no significant rain on the horizon. We need to be prepared,” says Chair Wilde.

A total outdoor water use ban is still in force for Wellington, Porirua, Upper Hutt and Lower Hutt.

Press Release – Greater Wellington Regional Council
Daily target water use (maximum) = 130 million litres (ML)
Wednesday’s water use = 137ML
Change from Tuesday = higher by 15ML

Water use jumped sharply yesterday, after two days of below-target water use. River levels are falling quickly towards pre-rain levels and the weather outlook indicates no rain for at least 10 days.

We need to maintain the level of water use below 130ML per day. Lower demand helps to preserve our water reserves longer.

Yesterday’s water supply came from:
Rivers: 86ML
Hutt aquifer: 56ML
Storage: increased by 5ML (within the Regional Council’s distribution network reservoirs)
Storage in Lake 2 was increased by 54ML

The water in the Hutt, Wainuiomata and Orongorongo rivers has cleaned up enough for us to treat. River flow rates continue to fall after the recent rain. We’ll have a better idea of how rapidly river flows will return to pre-rain levels in the next day or two.

We increased storage in Lake 2 yesterday by 54ML. Lake 2 is now 97% full and we expect to be able to top this up further over the next couple of days.

This morning’s 14-day weather outlook indicates no rain before the end of March, anticipating another spell of fine settled weather – we need to keep demand low.

The outdoor water use ban remains active.

News from Wellington Regional Council – March 20

Daily target water use (maximum) = 130 million litres (ML)
Yesterday’s water use = 122ML
Change from Monday = higher by 9ML

Wellington’s households and businesses are still doing a great job with water saving but we need to maintain this low level of water use. Lower demand helps to preserve our water reserves longer. This is necessary in case we quickly return to pre-rain levels of river water availability.

Tuesday’s water supply came from:
Rivers: 8ML
Hutt aquifer: 77ML
Storage: 37ML (Lake 2 – 31ML, Balancing reservoirs – 6ML)

The water in the Hutt River has now cleaned up enough for us to treat. As of 1.00am this morning the Te Marua treatment plant is back treating water from the Hutt River.

The Wainuiomata treatment plant is expected to be back treating water from the Wainuiomata and Orongorongo rivers some time today.

The rivers coming back on means that we can ease back on use of the Hutt aquifer and start topping up lake 2 to make up for the water taken when river water was too dirty to use. The lake level is currently sitting at 94% but we expect to be able to top this up over the next couple of days.

We’ll have a better idea of how useful this rain has been for water supply later this week, when we can assess how quickly water quality and flow rates are returning to pre-rain levels. Current indications are that water available from rivers should stay above pre-rain levels for at least 5 to 7 days.

If we get another rain event like this one over the next couple of weeks we will be discussing the easing of restrictions with the city councils.

The 14-day weather outlook has one possible day of rain before the end of March: Tuesday 26th. The outlook is for mostly fine and dry weather – we need to keep demand low.

News from Regional Council – March 19
water2

Rain across the region doesn’t mean we are out of the woods yet regarding water savings, says Regional Council chair Fran Wilde. “The good news is that huge savings are being made and it’s been raining. The catchments have received more rain than was forecast which is good, but because the rivers are too dirty to treat we have had to dip into the aquifer and our emergency storage.

“The other good news is that the rain means we now expect that it will take longer (about 5 to 7 days) for rivers to return to pre-rain levels. This means we can re-fill the storage lake and still have enough to meet demand.”

Ms Wilde says Wellingtonians deserve a huge vote of thanks for the effort they put into saving water and is encouraging the savings to continue.

“On Sunday demand dropped significantly and yesterday overall use was reduced to 113 ML – the second lowest demand since records began in 1997,” she said. (The lowest day on record was 112ML on 30 December 2012, a wet Sunday in the Christmas holiday period)

“However, we need those conservation efforts to remain for the foreseeable future. The rain is predicted to ease off soon and there will be another spell of dry weather, so we need to use the current rain to replenish the storage lake. Every litre saved now will help if we go into drought conditions again.”

The outdoor water use ban and water conservation steps by households and businesses in Wellington, Lower Hutt, Porirua and Upper Hutt over the weekend saw a reduction in demand from 145 million litres (ML) last Wednesday, to 125 ML on Sunday. On Monday the demand reduced to 113ML as people went back to work.

Last week’s statistics:

Day Water supplied (million litres/ML)
Wednesday 145
Thursday 140
Friday 133
Saturday 131
Sunday 125
Monday 113

News from Wellington Regional Council – March 18
The water supply situation remains at “approaching extreme”. A total outdoor water use ban started on Saturday and will be in place until further notice. While it’s been good to see the rain, this may be only a short-term relief. Water use was low yesterday but we need more of the same. We ask everyone to continue to take extra care with water use indoors.

Rain falling across parts of the region today and yesterday may not help in extending our water supplies. The river water is currently too dirty to treat. This has caused the Wainuiomata Water Treatment Plant to be turned off. The Te Marua Water Treatment Plant is now treating only stored water from the Stuart Macaskill storage lakes. We will resume treating river water as soon as it is clean enough.

The weather outlook has rain today and tomorrow before dry weather returns on Wednesday.

While water saving efforts to date have been pleasing to see (daily demand has dropped from 145 million litres (ML) on Wednesday 13 March to 125 ML yesterday), extra care with water use is still needed. Every litre of water saved pushes out the amount of time that our available water will last.

We are continuing to operate with only half of our usual reserve of stored water (one of the two water storage lakes at Te Marua is empty while we carry out earthquake strengthening and increase its capacity).

This situation update is a summary that combines the availability of water for supply and the level of water use compared with previous summers.

NZHerald: Wellington could run out of water in ten days

 

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