Pipes leak 70 swimming pools a week
An estimated nine billion litres of water is lost every year in Christchurch through leaks, broken pipes and faults – the equivalent of 70 Olympic-size swimming pools a week.
The number of leaks fixed each month has almost doubled over the past year, with contractors repairing more than 13,000 between July 2018 and the end of February.
City council staff warn water loss is expected to ‘‘rise significantly’’. At the same time, two months of water restrictions started in March so vulnerable wells could be repaired.
Despite Citycare – the councilowned maintenance company – prioritising major leaks and increasing staff, it is only getting through 80 per cent of the 50 leaks reported each day.
Other contractors could now be drafted in to help tackle the problem.
Ageing infrastructure and earthquake damage are thought to be part of the problem. The council said chlorination may have caused a spike in reporting of leaks since its introduction last year.
There is also concern leaky pipes could make the network susceptible to contamination.
Councillors have branded the situation ‘‘totally inadequate’’ and a major concern.
‘‘It’s not good enough, especially when we are asking the city to conserve water to fix the well heads,’’ Deon Swiggs said.
‘‘We need to be prioritising more maintenance funding towards the reticulation system.’’
The council is pumping vast amounts of money into improvements, with almost $490 million budgeted last year for water supply work over the coming decade, including $279m for mains renewals.
But it may not be enough. An earlier option – later dismissed – which city services general manager David Adamson suggested could bring pipes up to standard recommended spending $779m, $496m on mains renewals alone.
Despite Christchurch losing 18.4 per cent of its water – council staff are targeting 15 per cent – the city is not the country’s worst offender.
Auckland, Wellington and Dunedin all lose more from their networks, according to industry body Water New Zealand. The average supplier sees 23 per cent disappear.
Christchurch residents have long complained about the problem. One said was water ‘‘good enough to drink’’ had been ‘‘gushing’’ across the road near Hagley Park at Peterborough St for almost two months.
Another had to wait six weeks for the council to assess a leak that was flooding a footpath in Woolston, and in January an apparently burst pipe sent water shooting into the air in a suburban Mt Pleasant street.
The city council uses approximately 49 billion litres each year, for everything from community drinking water to firefighting.
But 17.9 per cent is lost – around 8.7bn litres in the year to June 2018, or 24 million litres a day.
On Banks Peninsula – also run by the city council – the 512m litres lost accounted for 36.2 per cent of the water supply.
By comparison, the 9.2b litres lost in the council area is six times the 1.57b litres bottling company Cloud Ocean Water has permission to take annually at its Belfast site.
Leaks in the city’s 3600km of water supply pipes are not the only problem. Faulty meters and overflows from storage tanks play a part also.
The council assesses lost water every five years, measuring 20 per cent each year.
Head of three waters and waste John Moore told The Press: ‘‘The percentage is expected to rise as we are testing zones that haven’t been tested in a while, and it is expected that more leaks exist in those zones due to ageing infrastructure.
‘‘There has been an increase in the number of leaks reported since the introduction of chlorine to our water network, so chlorine may well be one factor.
‘‘The increase may also be due, in part, to a greater awareness of the council’s water conservation campaign and the restrictions introduced in March.’’
Maintenance teams repaired nearly 2100 leaks in February, almost double the 1150 a year before. The problem area was the number of ‘‘minor’’ leaks, Moore said said. Citycare has about 1300 jobs outstanding. On average, it receives 50 jobs a day and completes 40.
Council infrastructure committee chairwoman Pauline Cotter said new smart technology could pinpoint leaks and infrastructure weaknesses, and improve response times.
‘‘We have physical, vulnerable infrastructure, so rather than going through and replacing it all, if we look at smart systems . . . that will be a good way of targeting these things before they blow out or leak.’’
Water New Zealand technical manager Noel Roberts said water loss nationwide was ‘‘shocking’’ compared with international standards, with companies overseas fined millions of pounds for missing leakage targets that are often much lower than here.
But he said upgrading infrastructure was tough and expensive.
‘‘These are multimillion-dollar assets installed over a long period of time, so to upgrade it at once would be a nightmare.’’