BROKEN PIPES, BROKEN PROMISES:

Commentary by Andi Cockroft, Chair, CORANZ

Why New Zealand’s Ageing Wastewater System Is Failing Rivers, Estuaries – and Recreational Fishers

New Zealand likes to imagine itself as a clean, green country with world-class water. Yet with every passing year, the illusion becomes harder to maintain.

This week’s example came from the Mahurangi Harbour, where oyster farmers have again been shut down because of another wastewater overflow. It is only the latest in a long and growing list of sewage failures contaminating rivers, estuaries, shellfish beds, and fishing grounds from Northland to Southland.

On the surface, the RNZ article is about oysters, farmers and compensation. But beneath that story sits something far bigger and more troubling: a wastewater system that is ageing, underfunded, past its design life, and drifting toward weakened standards at exactly the moment we need stronger ones.

And yes, this directly impacts recreational fishers — coastal, estuarine and freshwater — even if no one in government seems willing to say it.

1. Mahurangi: A Symptom of a Much Larger Crisis

In mid-November, Watercare confirmed that around 86 m³ of wastewater mixed with stormwater had again spilled into the Mahurangi River.

This comes just weeks after a much larger 1200 m³ spill in October.

Under MPI rules, any confirmed sewage contamination in commercial shellfish waters triggers a mandatory 28-day shutdown. The logic is sound: enteric viruses survive in oysters. One contaminated harvest could cripple consumer confidence and make people sick.

But here’s the part recreational fishers and gatherers will notice:

Every time this happens, the harbour is effectively unsafe for everyone, not just commercial operators.

Still, the public messaging remains strangely split:

– Commercial oyster farms: immediate closure

– Recreational gathering: vague advisories

– Recreational fishing: no formal closure despite the same contamination moving through the same water

The result is a double standard.

Commercial harvesters have protections. Recreational harvesters and anglers get “monitor the situation” and hope for the best.

Why?

Because commercial farms are part of a regulated export chain. Recreational people — who eat what they gather and use the same waters — are not.

It’s the same harbour. The same contamination. The same health risk.

Only one group gets decisive protection.

2. “Wet-Weather Overflows” — The Magic Words That Excuse Anything

In the October spill, Watercare admitted a “technical failure” and oyster farmers were compensated.

But the November spill?

That one is dismissed as a “wet-weather overflow” — the classic escape clause built into most council wastewater consents.

In other words:

“It rained too much, the system couldn’t cope, and therefore no one is liable.”

This isn’t a glitch — it’s built into the system.

In nearly every region, wastewater networks:

– overflow by design during heavy rain

– rely on archaic combined stormwater/sewage systems

– treat rivers and estuaries as pressure-release valves

– have legally permitted discharge rights that would shut down a private industry overnight

– and are allowed to call these failures “inevitable”

If any farmer, forestry operator, or recreational fisher polluted water this consistently, penalties would be severe.

But when councils and government-owned water companies do it, the rules are different.

3. A National Pattern: Ageing, Failing, Under-Monitored Infrastructure

The Mahurangi infrastructure failures are not isolated. They reflect a national pattern:

– Northland: repeated sewer overflows into the Hatea, Kerikeri and Whangārei Harbours

– Auckland: dozens of annual “dry-weather” overflows, hundreds of “wet-weather” events

– Wellington: pipes bursting under the CBD, sewage geysers, excrement flowing into the harbour

– Wairarapa: chronic plant non-compliance affecting Ruamāhanga tributaries

– Canterbury: overloaded ponds forced to discharge untreated effluent in flood conditions

– Southland: wastewater failures affecting estuaries used by whitebaiters and anglers

In almost every region, wastewater infrastructure is:

– at or past end-of-life

– built for populations half today’s size

– running on consents granted decades ago

– reliant on “wet-weather bypasses” that are no longer acceptable

– patched rather than modernised

– and increasingly expensive to fix

The minister recently acknowledged that more than 60% of New Zealand’s 330 wastewater plants will need new consents within 10 years — a staggering proportion.

Yet the policy response has not been strengthen standards.

Instead, central government is rolling out…

4. New National Wastewater Standards — With a “Cost-Cutting” Focus

Two days before the Mahurangi spill story broke, the government introduced new streamlined national standards for wastewater plants. These were framed as:

– saving $830 million over 35 years

– reducing the cost of consenting

– preventing councils needing “overly strict” upgrades

But there’s an obvious risk:

If the priority is lower-cost consents, the outcome will be lower-cost infrastructure.

The country may end up locking in marginal, underperforming plants for another generation.

Councils are already struggling with budgets. Tell them they must meet high standards and they will protest. Tell them the standards can be relaxed — or “streamlined” — and they will eagerly take the path of least resistance.

The timing could not be worse.

At a moment when wastewater spills are escalating, and when rivers and estuaries need stronger protection, the regulatory system is trending toward leniency, not rigour.

5. What This Means for Freshwater & Estuary Recreational Users

Freshwater anglers may see a coastal oyster story and think “not my problem.”

But wastewater failures are whole-of-catchment problems:

– rivers that hold trout are downstream of towns

– lakes receive stormwater and wastewater bypasses

– whitebait spawning sites sit at the tidal margins

– estuaries where many anglers fish are the receiving bowl of everything upstream

Every overflow carries:

– E. coli

– viruses

– ammonia

– nutrients

– heavy metals

– micropollutants

These directly influence:

– algal blooms

– invertebrate populations

– trout and salmon spawning success

– water clarity

– safe wading

– contact recreation

There is also a clear equity issue:

Commercial aquaculture gets hard shutdowns. Recreational users get soft warnings.

If sewage contamination is serious enough to halt a multi-million-dollar industry for 28 days, why is it still considered acceptable for children to swim or anglers to fish?

The only difference is economic visibility, not public health risk.

6. The Whitebait Parallel

The recent whitebait reports highlight:

– degraded water quality

– sedimentation

– stormwater pollution

– wastewater failures

– habitat loss

The Mahurangi event fits exactly into this pattern.

The contaminants that close oyster farms also threaten whitebait spawning, estuary stability, and inshore fish nurseries.

The connection is simple:

When wastewater management fails, freshwater and coastal recreation both suffer.

7. What Must Demand

A credible national wastewater reform should include:

1. Zero-tolerance for routine untreated overflows

2. Strong national environmental standards

3. Mandatory public notifications for all spills

4. Recreational harvest and recreation-site closures

5. Regular compliance reporting with penalties

6. Real investment in infrastructure

7. Catchment-scale management

8. Conclusion: A Country Treating Waterways as Infrastructure Outlets

The Mahurangi shutdown is not an isolated failure.

It is the visible tip of a wastewater system that:

– overflows by design

– is decades behind renewal cycles

– is drifting toward weaker regulation

– and does not protect recreational users

Commercial operators get decisive intervention because the economic risk is obvious.

Recreational users — the largest stakeholder group in New Zealand’s outdoors — get little more than cautions and hope.

Until New Zealand confronts its decaying wastewater networks and stops treating rivers as drains, recreational anglers will continue to face:

– reduced access

– degraded habitats

– risk to health

– declining fish stocks

– erosion of the outdoor heritage they value

If it’s unsafe for oysters, it’s unsafe for all of us.