The country's water workforce is struggling to keep up with huge growth and infrastructure demands as decades of underinvestment in pipes is finally being addressed.
Water New Zealand's latest National Performance Review shows $1.6 billion was spent on capital improvements last year.
That's an increase of 44 per cent for water supply and 30 per cent for wastewater expenditure compared to the previous year.
The 2019/2020 review covers about 90 per cent of the population and 42 water suppliers.
But the Department of Internal Affairs thinks the cost to fix New Zealand's woeful pipes could be as much as $110 billion over the next 30 to 40 years.
Coming up with billions of dollars worth of investment for the problem is only half of the equation.
Someone actually has to physically do the work, too.
The review found, on average, only 77 per cent of budgeted capital expenditure was spent in the past financial year.
Water New Zealand chief executive Gillian Blythe said the lack of people to deliver projects had been widely acknowledged as a key reason for this gap.
The review revealed the workforce was struggling to keep up with existing levels of growth despite a 25 per cent increase in the number of people employed in the past four years.
"High levels of vacancies have continued to be a feature, with an 8 per cent vacancy rate across the three waters sector, Blythe said.
"This has flow on impacts for the ability of service providers to keep pace with the levels of service being demanded by consumers and regulatory standards.
Audit New Zealand has recently raised concerns about the issue with Wellington City Council.
The council has budgeted about $678 million over the next 10 years to deliver a three waters capital programme.
But audit director Karen Young said delivery was at risk because of other large infrastructure projects within the region and nationally, which are competing for limited resources.
"This, coupled with the uncertainty of Covid-19, could result in the council failing to deliver its capital programme in future years, which could impact on service levels."
A Wellington Water Long-Term Planning update report published earlier this year said the capacity and capability of the local market was currently sized for historically static levels of funding.
Wellington Water manages water assets for the Hutt, Porirua, Upper Hutt and Wellington City councils, South Wairarapa District Council and Greater Wellington Regional Council.
The company commissioned an independent review of local sector capability and capacity, which it is due to have received.
Last year, Wellington Water pitched an accelerated apprenticeship scheme for an essential Three Waters workforce to retrain 100 people.
The company unsuccessfully made the pitch to the Government as a shovel ready Covid-19 response project.
Wellington Water Group Manager Customer Operations Kevin Locke said in the pitch large-scale investment was challenged by fragmented ownership and a construction sector hamstrung by outdated work methods.
"This work would be done more quickly, more efficiently, in a way that builds lasting benefit for the nation and supports an innovation-oriented economy."
Local Government Minister Nanaia Mahuta has previously said she is working with Water New Zealand on what it's going to take to grow a dedicated water workforce.
She gave the example of a team of technicians who were flown over from Germany in the middle of the Covid-19 lockdown to repair two broken sludge pipes in Wellington.
"It only served to highlight to me the amount of planning and investment we must do … so that we have our own workforce we can rely on for all aspects of servicing our network", she said at a public meeting.
Blythe said the situation created opportunities for school leavers and those looking for a new path.
"The water sector is a great place to work for those interested in giving back to their communities and the environment."