Tauranga City Council water supply experts Rodney Clark and Peter Bahr with one of the microfiltration tubes that clean Tauranga's drinking water. Photo / George Novak
By Samantha Motion
Summer is months away but Tauranga residents are already being asked to start conserving water as low rainfall puts drinking water supplies under extreme pressure.
The Tauranga City Council says a fourth summer in a row of water restrictions is likely - and they may arrive earlier and be stricter than in the past.
And Bay of Plenty Regional Council is also preparing for the possibility of a water shortage.
Both councils have urged residents, as well as horticultural and agricultural water users, to start thinking about summer water use now.
Average daily water use in Tauranga is 43.7 million litres, but that can jump to 150 per cent of normal daily demand in the summer peak, mainly due to outdoor use. Restrictions can be triggered at 50 million litres a day due to treatment limitations.
City council water services manager Peter Bahr said the council felt it had to warn residents early this year after a dry winter and more population growth.
"Our concern is that our water resources are going to come under constraint this year, so we are wanting to go out to the community earlier and let them know.
"Water is precious and we want to look after it."
He said last month was Tauranga's driest September for 50 years and rainfall for the year was about 30 per cent down on average.
"It's a significant issue in terms of water runoff and the way in which streams are performing.
"It's significantly drier."
He said the city had sprinkler bans the past three summers, generally between December and March.
This year, restrictions might start as early as November and there was a higher chance of going a full hose ban.
A hose ban has never been used in Tauranga, but the Western Bay of Plenty District Council implemented one in Te Puke for a few weeks in February.
Bahr said water restrictions were not necessarily a bad thing.
"It's to ensure that we use water efficiently and effectively.
"If we allowed people to use water In an uncontrolled manner, we'd need to build additional treatment capacity that potentially will only be used in summer."
He said people should avoid using drinking water for activities such as gardening.
Passionate gardeners could look into rainwater tanks or water bores for an alternative supply.
Two Tauranga water bore companies reported a massive increase in demand for new bores.
Tony Quaife of BOP Water Bores and Maintenance said he was "absolutely flat out".
"I had the busiest winter I have ever had," said Quaife, a veteran of 13 years.
"Everyone is saying the last two years we have had water restrictions and it's bound to happen again so everyone wants to get in early."
"People got caught out last year and lost lawns and shrubs that are expensive to replace."
Murray Savage, who started Papamoa Water Bores two years ago, said he was doing two bores a day, many of them for new builds.
"Normally it would start about now but it's been going like this for the last couple of months.
"I'm 100 per cent up on last year."
Regional council water shortage event manager Steve Pickles said the current dry conditions and forecast over the next few months were heading towards low stream flows and pressure on water resources
"Preparing now by planning for periods of potential water restrictions is critical to navigating your way through the dry spell."
In exceptional circumstances, the council can issue a water shortage direction under the Resource Management Act and put temporary extra water use restrictions in place to protect waterways.
The measure has never been used in the Bay of Plenty, but Pickles said a drought earlier this year brought it close to restrictions that would have affected horticulture and agriculture in particular.
The council managed more than 1400 consents for water takes in the region. It was updating its operating procedure for a water shortage.
Long-term weather forecasting offers some hope for this summer.
MetService meteorologist Jake Cope said a La Niña weather pattern was forecast for the Equatorial Pacific.
If it's impacts reached New Zealand around late December, as predicted, it would bring a "slightly wetter" summer than seen in the past couple of years to the upper North Island.
Tauranga City Council is building the city's third water treatment plant on the Waiāri Stream to increase supply for its growing population, but the project has been hit by delays and huge cost increases.
The council initially planned to have the plant built by 2015, but put it on hold in 2012 after the Global Financial Crisis.
It was revived in 2016 and physical works started in 2018. The project was expected to be finished by 2021, but that has been pushed out to 2022.
The cost estimate reported in 2017 was $115 million. A budget of $144m was set in 2018 but estimates in September projected a worst-case scenario where it could hit $189m. It was more likely to land around $184m - a 60 per cent increase on 2017.
The council put the delay and projected increase down to redesigns, additional work necessary after "geotechnical complexities in construction" and managing increased construction risks, and higher tenders than expected thanks to a contractor-favouring market.
The new plant would serve a population of 35,000, add an initial treatment capacity of 15 million litres per day, and "have an immediate impact on balancing the treatment capacity and flows and for the city".
Asked what would come after Waiāri, the council said the next big challenge would be reconsenting existing water takes, which expire in 2026.
"Besides planning for the future, it's increasingly important the community considers the effects of our changing climate and adopts more sustainable habits when it comes to how we use drinking water.
"Water is a precious and finite resource and it's important we start treating it as such."
Tauranga's other two water treatment plants are in Joyce Rd in Pyes Pa and Ōropi. Together they can treat 63 million litres of water per day, drawn from two spring-fed streams: the Tautau and the Waiorohi.
Water restriction levels
Tauranga City Council has three levels of water restrictions:
1. Sprinkler ban – No sprinklers are allowed, people can water gardens using a handheld hose between 5-8am and 7- 10pm.
2. Hose ban – no sprinklers and hoses allowed, watering of gardens by watering can or bucket only.
3. Total outdoor water use ban – no watering of gardens allowed to ensure we have enough water available for households.
Source: Tauranga City Council
Water conservation tips
- Try to avoid using drinking water to wash the house or hose hard surfaces
- Consider the timing of putting in new lawns and gardens
- Mulch your garden to keep moisture in
- Soak your garden every few days rather than a quick drink every night to encourage deeper roots
- Water during the cooler hours of the day (early morning or late evening) to reduce evaporation
- Pick plants suitable for the local climate that don't need as much water.
Source: Tauranga City Council
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