Much more must be done to make wastewater treatment plants in Horizons region towns comply with regulations.
And unless the Government coughs up that work will cost region ratepayers, Horizons Regional Council environment committee chairman Gordon McKellar said.
"It's hard on a small community. We do acknowledge that. Hopefully central government could help."
Earlier this year Horizons sent all the district and city councils in its region a letter, reminding them to secure funding in their long-term plans for any upgrades needed.
In June only 34 per cent of the region's wastewater treatment plants were fully compliant. Of those that aren't, eight are non-complying and 22 are significantly non-complying.
"I was quite shocked by that result. Last time we reported there were not as many significant non-compliances," McKellar said.
All the plants in the Tararua District are significantly non-complying. Plants at Feilding, Taihape, Hunterville, Bulls, Ratana, National Park, Ohakune, Raetihi, Whakapapa and Whanganui Prison all need work.
As partial explanation, McKellar said higher standards have been set in the One Plan and more monitoring may be happening than previously. Rainfall is also heavier, and some of the centres have ageing pipes.
Some of the non-compliances are about too much being discharged - which can be due to stormwater getting in through failing pipes or illegal connections. Others are about the content of the discharge - too much ammonia, E. coli or solids that will have environmental effects.
Some of the councils are in the process of renewing resource consents, but the process is lagging. Horizons told local authorities not to wait until their consent expired to apply for a new one.
"That has often extended quite a number of years. We have sent a message out that that sort of approach isn't going to be acceptable."
The council issues abatement notices, which can be followed by prosecution. The penalty is generally a fine - often less than $1000.
Whanganui District Council is being prosecuted over the state of Kai Iwi Stream, which was off-limits for swimming during parts of last summer.
The plant at Whanganui Prison has exceeded the amount it's allowed to discharge. So have plants at Taihape, Hunterville, Bulls, Ratana, National Park and Whakapapa.
Hunterville's new floating wetland system has been discharging E. coli faecal coliform bacteria as well as too much fluid. Its consent doesn't expire until 2037.
The Raetihi and Ohakune plants have exceeded the amount of solids they can discharge and are in the process of renewing their consents.
Non-compliance by towns could anger dairy farmers, who are expected to prevent their businesses affecting water quality.
"I don't want to see a double standard. We have to make sure there's a level playing field," McKellar said.