Local authorities are on high alert this time around.
The country’s water regulator and Wellington Water have agreed to a goal of reducing water loss by seven million litres of drinking water per day by this summer to avoid severe restrictions.
Wellington Water manages water assets on behalf of its shareholding councils –Hutt, Porirua, Upper Hutt and Wellington city councils, South Wairarapa District Council and Greater Wellington Regional Council.
The water company says it’s focused on keeping water in the pipes, reducing water use, and adding supply to address the shortage problem.
Towards the end of last year, the region experienced the highest level of leaks in the network in many years. Councils have since put more money into finding and fixing leaks and Wellington Water has reported positive progress.
As of January, there was a backlog of 1720 leaks in the public network, which has been reduced to 509 as of last month – which is less than the backlog of 605 leaks in the private network.
Wellington Water regulatory services director Charles Barker noted the number of private leaks now exceeded the number of leaks on the public network for most councils.
“With the progress made on public leaks and a marked increase in private leaks, we will also be looking to encourage residents to find leaks on their properties and fix them as soon as possible.”
A message for Wellington City Council near a water leak on Ngaio Gorge Road. Photo / Mark Mitchell
Wellington Water fixed a total of 7007 leaks across both the public and private networks in the first half of this year.
However, Wellington Water has reported Porirua City Council’s funding for leaks is forecast to run out in April and Upper Hutt Council’s by the end of January – just as the region is entering the critical summer risk period.
Barker said the water company was working on additional advice for these councils for funding to ensure leak repairs could continue at pace for the remainder of the financial year.
“Without this, we expect to see the backlog of leaks begin to climb again in the second half of the financial year.
“This would mean we would not be able to provide assurance that the reduction in water demand [seven million litres daily] can be sustained past February 2025. If the backlog of leaks was to climb, we would be consuming the reduction achieved.”
Porirua City Council infrastructure general manager Mike Mendonça said if and when there was a requirement for more money, the council would discuss this with Wellington Water and reallocate funding if required.
He noted a backlog of 240 leaks in March had been reduced to just 32 without Wellington Water dipping into $792,000 worth of contingency funding.
“With underground assets, there is often uncertainty about the nature and location of a leak, and the costs can also be difficult to estimate with any accuracy,” Mendonça said.
Upper Hutt City Council asset management and operations acting director Gunther Wild said the council had allocated the amount of money for leaks that Wellington Water had previously asked for.
“Wellington Water has made a call to accelerate the rate of repairs and this is depleting the budget at a faster rate than was forecast. Should repairs continue at that faster rate, it is forecast that funding could run out before the end of the financial year.”
Efforts to date have halved the backlog of leaks in Upper Hutt.
The council was cognisant of getting the balance right between leak repairs, or “putting on bandaids”, and investing in pipe renewals, Wild said.
“Upper Hutt City Council will respond to quantifiable needs as they arise, as continually seeking additional funding for short-term fixes without an assurance of achieving long-term value for money outcomes is not a responsible use of ratepayer funds.”
Pipe renewals are nowhere near what’s needed
Wellington Water has told councils the region needs to replace 100km of drinking water, wastewater and stormwater pipes each year.
Just 9km of pipes are forecast to be renewed this financial year based on council funding, Barker said.
“Without increased and sustained investment into renewals, the condition of the asset base will deteriorate and further investment into leak and burst repairs will be needed, which becomes an increasingly inefficient way to manage the network and control water loss.”
These council-controlled organisations (CCOs) will be able to borrow up to five times their revenue, which will come from water charges.
Councils in the region are still working through this.
Reducing water use is critical to avoiding severe restrictions
Wellington Water has installed three valves in the suburbs of Brooklyn, Johnsonville and Melrose to reduce water pressure, Barker said.
“Dropping the pressure in the system reduces how much water is flowing through the pipes and reduces the number of new leaks occurring, as well as extending the service life of the pipes downstream of the valves.”
Modelling shows this had provided savings of 300,000 litres per day and is expected to reduce the number of new leaks by as many as 40 per year.
Wellington’s metropolitan councils have also agreed to fund a joint business case into residential water meters.
Wellington Water chairman Campbell Barry said Hutt City Council has funded its share of the business case, has approved water meters and will start rolling them out in the next financial year.
Porirua City Council was in a similar position, he said.
Wellington City Council has allocated money to implement water meters in the later years of its Long-Term Plan, Barry said. This means the plan will be up for debate and reviewed again by a new council before work on physically installing water meters gets under way.
Upper Hutt had only funded its share of the business case, Barry said.
Barry described the consensus as a bit of a mixed bag.
“It’s a lot further than we’ve ever been on water meters, which is a positive step, and two of the four metropolitan councils rolling them out will start to make a real difference.”
Kāpiti Coast District Council introduced water meters in 2014.
Within 18 months of them being brought in, 443 leaks had been found and 97% of them were fixed, leading to a 90% decrease in water use.
It was, however, a move that came at the highest cost for advocate and Mayor Jenny Rowan who ultimately paid for it with her job.
Additional water supply expected by the end of January
Work is under way to increase capacity at the Te Mārua water treatment plant from about 80 million to 85 million litres per day up to around 120 million litres per day.
The Te Marua water treatment plant in Upper Hutt. Photo / Wellington Water
Barker said this work was being delivered in stages and they are on track to deliver 20 million litres of additional supply into the network by the end of January 2025.
There are also plans for more storage lakes to supply the plant, he said.
“This additional storage will allow us to capture and store more water when it is plentiful in the winter months, providing an important source of water for the region in the summer months when the river levels drop away.”
Water regulator is ready to intervene if necessary
Water Services Authority Taumata Arowai will actively monitor the efforts of Wellington Water and its council owners to reduce the likelihood of acute water shortages this summer.
Head of regulatory Steve Taylor said the authority was ready to intervene if needed.
“Looking at progress against Wellington Water’s plan to date, our monitoring indicates that at this stage Wellington Water and its owner councils appear to be on track to meet their goal to reduce water loss by 7.4 million litres of drinking water per day by this summer.”
However, Taylor warned cities were still likely to experience moderate water restrictions.
“Restrictions are used commonly around the country over the drier summer months to help ensure that people continue to have enough water for their basic drinking and hygiene needs. It will remain important for Wellington, Hutt Valley and Porirua communities to keep using water responsibly and follow any restrictions.”
Wellington has already moved to Level 1 water restrictions, which means sprinklers can only be used every second day.
Sprinklers and irrigation are banned in Level 2 and people should only water their gardens by hand.
In Level 3, all outdoor residential water use is stopped.
Level 4 means there is a significant water shortage and people also need to reduce indoor water use like taking two-minute showers and limiting laundry to one load per person per week.
Georgina Campbell is a Wellington-based reporter who has a particular interest in local government, transport, and seismic issues. She joined the Herald in 2019 after working as a broadcast journalist.
