With a high water table common at this time of year, the drain that ran into the river contained a lot of rotting organic material, which, combined with high tides holding the Awanui River water back, created a "bubbly mess" that eventually began to putrefy.
But the health of the river would improve thanks to the regional council's proposed seven-year, $15 million Awanui scheme project, due to start in 2020. The work was designed to improve flood protection for Kaitaia and Awanui, but would also have a positive impact on the health of the river.
"Among the environmental benefits will be more stable riverbanks, with less scouring and associated erosion, and the removal of material obstructing flow within the river," Mr Howse said, adding the council worked with landowners to ensure new work would not lead to erosion or sedimentation in the river and Rangaunu Harbour.
The project was designed to protect people and buildings from a one-in-100-year flood, and agricultural production from one-in-20-year floods. It would also reduce flooding by seawater of low-lying and reclaimed land around the southern end of Rangaunu Harbour to no more than once in 20 years, and reduce the volume of sediment carried by the river and discharged into the harbour.