An investigation into the suspected discharge incident in the Heathcote River is continuing after several hundred dead fish were found on Thursday 2 March.

Environment Canterbury said it suspects the deaths were caused by a discharge incident but don’t yet know the source of the discharge.

Spokesman Nathan Dougherty said during the clean-up of the area last week, a total of more than 500 fish were collected and disposed of.

“Our team is out checking the river again today, to see if there are any freshly deceased fish or affected wildlife.

However, our monitoring since the initial incident response indicates the probability of an ongoing incident to be low.

Investigators are working on potential helpful leads which may identify a contaminant that could be involved in the incident.

Pollution warning signs will remain in place until we are more confident that there is no ongoing discharge or effect.

Environment Canterbury is warning residents to avoid the area in the vicinity of Connal Street, Cumnor Terrace, Long Street and Garlands Road, and to not carry out any recreational activity on or in the water area.

“Do not come in contact with the water, keep dogs away, and don’t eat fish from the area. We will let people know when it’s safe to return.

We continue to ask for reports from the public of any unusual or suspicious happenings in the area — people can call us on 0800 765 588. Anonymous reports are welcome.”