Hamilton councillors need greater oversight of wastewater calls - Sarah Thomson

Tuesday, 8 April 2025

A lack of space in the sewerage system has put the brakes on new housing developments in large parts of Hamilton, particularly in the south of the city (file photo).

Hamilton’s overloaded sewer pipes have scuttled about 750 potential developments in a little over two years, council figures show.

The sewerage situation prompted a city council clamp-down in 2023, effectively shutting down development in large parts of the city to avoid putting the system under extra pressure.

But the constraints - and the council’s response - seem to have “severely dented the confidence” of investors, city councillor Sarah Thomson says.

She’s concerned the council might have gone too hard and fast with a conservative risk modelling approach that has “large costs and trade-offs”.

Strategic growth and district plan committee chairperson Sarah Thomson wants more political oversight over development restriction decisions.

So Thomson’s calling for more political oversight of such decisions and a review of the “risk appetite” on wastewater.

Since March 2023, the city council’s received more than 1600 wastewater capacity queries for “brownfield” [including infill] development areas.

“Of those, 46% (754) have been advised of network constraints and subsequently no development has taken place,” a staff report for Tuesday’s strategic growth and district plan committee meeting said.

“No resource consents have been granted in constrained areas in this time, beyond those council has previously committed to.“

There was “little warning before parts of the city were ‘turned off’ for development”, said a report from Thomson - the committee chairperson.

“Good” developments were turned down and developers were left frustrated and with “no certainty as to when they will be able to develop”.

Hamilton’s treatment plant on Pukete Rd is a key part of the city’s wastewater infrastructure.

“From the feedback I’ve received, the constraints and the way we’ve handled them have severely dented the confidence of people investing in Hamilton.”

Her committee is due to meet on Tuesday to discuss a major Wastewater Capacity - ‘State of the Nation’ staff presentation.

Wastewater was the reason the council introduced development restrictions over large parts of the city in 2023.

Targeted areas in the south-west, the south-east and pockets of St Andrews, Rototuna and Nawton currently face significant development restrictions due to the constraints.

Thomson told the Waikato Times on Monday the restrictions had been an “operational decision” by staff, which she acknowledged took into account the previously expressed “risk appetite” of councillors.

But, in hindsight, she said councillors should have had a role in decision-making.

“At the sharp end I’d like to see more political oversight of such operational decisions” and she wanted a review of the “risk appetite” when it came to wastewater.

Glenview is one of the areas that have faced new development restrictions because the wastewater system is under pressure.

Thomson said she was “troubled” by how quickly and unexpectedly large parts of the city were closed off from development and “the lack of visibility elected members [councillors] have had regarding how those decisions were made”.

“It’s crucial that elected members have greater oversight of this going forward.”

Thomson’s report said some affected areas were experiencing “actual overflows” in wet weather but other areas’ restriction decisions were based on modelling which councillors needed to understand and sign off on going forward.

The feedback she’d received meant “I’m concerned we may be taking a very conservative approach to modelling the risk of wastewater overflows that carries with it large costs and trade-offs”.

“We need to ask, and determine as elected members, are our current risk settings right or could we allow more housing in some areas of the city if we accepted a slightly higher level of risk?”

One key concern was the city might be turning down feasible developments now while reserving capacity for future growth in other parts of the city that won’t be doable for “years”.

“We need to be pragmatic and focus on developments that are here and ready to go today, and receive a return on the investment in infrastructure we’ve already made.”

Thomson said councillors needed to better understand what the $1 billion for wastewater outlined in the long term plan would deliver.

Addressing areas with high-risk network overflows is part of wastewater system upgrades, the staff report said.

It noted developers were presenting infill development plans in areas with existing constraints but said: “These areas are either not prioritised for investment or will take several years to complete the funded projects needed to resolve the capacity issues.”

It also said there was about $133 million worth of wastewater projects not currently funded.

An earlier council statement noted Hamilton capacity could increase if the proposed waters council controlled organisation with Waikato District Council goes ahead. A final decision on that is expected in June.