"This incident had the potential to impact on sewer services to a large area of Maraenui, including the Maraenui shopping centre," he said.
"A blockage of this nature can cause a prolonged sewer overflow event that presents a significant public health risk to our communities and would be very expensive to remedy.
"Given the nature of the material removed from the drain and its close proximity to the shopping centre, there was a very real and significant risk of having to excavate in the roadway and around shops to restore the drains to operational conditions."
The sewerage line branches out and connects to at least 100 houses and businesses. So if it was left longer it could have caused sewage overflow and meant many people would not be able to flush their toilets while the problem was being fixed, Mr Kingsford said.
The occupiers of the house where it was believed to have been caused were spoken to but had only lived at the property for a few days and were unlikely to be the culprits.
Council would continue to investigate and if it found irrefutable evidence pointing to an individual or individuals then council would seek reimbursement of costs.
There is an annual budget for sewerage blockages but this event would probably equate to at least 10 or 20 normal obstructions and could push them over the budget, he said.
Council communications and marketing manager Fiona Fraser said the blockage was expensive to fix with the trucks alone costing about $10,000-$15,000 to come out and help.
"The sewerage pipe was in such a state that it came very close to flooding a lot of houses and businesses in the area."
Council staff and contractors spent all Thursday and some of Friday to clear with the sewer now being restored to full operational, unimpeded flow.
Anyone who sees people dumping of this sort of material into drains should contact their local council immediately because if left it could affect a lot of people.
What can go into sewerage:
Domestic sewerage - i.e number 1s & 2s plus toilet paper
Waste disposal
Grey water (laundry and dishwasher)
What can't go into sewerage:
Napkins
Nappies
Sanitary pads
Anything solid that is larger than can fit in your closed fist
Definitely not slides, bikes, barbecue grills, toys, plastic bags etc.
And never lift a manhole cover.