People walking near central Christchurch have spotted an unusual white grey clouding in the Avon River this morning, prompting an investigation from Environment Canterbury.

An Incident Response team visited the area to check the water and begin an investigation into what caused the sudden change in colour.

The agency said it can be challenging to pinpoint the exact source of a discharge in a busy urban waterway, and enquiries are continuing.

The unusual colouring has mostly cleared, and there have been no reported impacts on wildlife.

Anyone who notices possible contamination or other environmental concerns is encouraged to report it on 0800 765 588 at any time, or through the Snap Send Solve service at this link: https://bit.ly/4p7lBWF