The recent "discharge event" in Hawke's Bay highlights the fact that in-ground infrastructure is becoming overloaded thanks to booming development and the impact of climate change.
But in Napier City's case, it also points to deficiencies in their forward planning.
A prudent council listens to its engineers and plans a works programme that stays ahead of a replacement schedule and makes sure new development is wedded in without overloading the system, usually by enlarging the existing pipe network.
Unfortunately pipe upgrades cost big money and cause disruption, and politicians have a nasty habit of deferring such works to keep rate rises artificially low. This may not be a problem if growth is reasonably slow, but as soon as there's a boom, look out!
The classic case is Auckland's North Shore: the pre-amalgamation councils had adequate systems for their bay-side villages, but the sustained boom in the decades after the harbour bridge was built caught them out.
Their plans and budgets didn't keep pace, so by the 1990s there was literally a flood of intermingled wastewater coming down from the now-suburban hills and industrial valleys to swamp the town centres and adjoining beaches.
A massive upgrade programme ensued – but is still not completed sufficient to cope, which is why places like Takapuna beach are unsafe for swimming on more days than anyone cares to admit.
Hawke's Bay may not have the "iconic" urban beaches of the Shore, but its waterfront is still valued and we do have the remnants of Te Whanganui-a-Orotu, otherwise known as Pandora Pond or Ahuriri Lagoon.
Flanked on two sides by Napier city's two main growth areas: Ahuriri, with its phalanx of bars and eateries and intensified residential, and the commercial/industrial precincts that now stretch around to the expressway in the west.
An area which has been allowed to develop and intensify without adequate upgrading of the city's old wastewater system, it seems, because how else to explain the recent discharge of sewage into the lagoon – a lagoon that is the only safe spot for swimming and water sports for much of the year, not to mention an estuarine haven for wildlife.
Yes, an increase in the number of extreme weather events due to our changing climate is, to be charitable, a partial excuse. But any planner or politician worth the name has known this would happen for at least 20 years.
And yes, there is now a $20 million works programme under way to redress the issues. But it is spread over a decade, and in any event is only a fraction of what is actually required to make the city water tight.
Let's be clear: this is a political mess, not an engineering one. Alan Dick was elected in 1989 on a platform of deliberately cutting the spend on service infrastructure. Successive mayors since – Barbara Arnott and Bill Dalton – have continued to oversee an "only as needs must" regime.
In 2015 Dalton crowed about the city's low debt and claimed its infrastructure was "in excellent shape" – while hotly disputing a local government commission report's assessment that the city was about $120m under-done in provision of essential services.
Now the ducks are coming home to roost – or would be, if their nesting places were cleaner.
Given NCC can instantly find $5m to fix McLean Park's drainage but still be forced to pump sewage into the lagoon to prevent it flooding the streets, the upgrade programme urgently needs accelerating.
It's time Napier's council acted responsibly, forgot about vanity velodromes and artful aquariums, and fixed the cesspool its inaction has created at its front door.