The investigation into the suspected discharge incident in the Heathcote River is continuing.

Around 300 dead fish were found in the Heathcote River on Thursday 2 March.

Authorities suspect their deaths were caused by a discharge incident but don’t yet know the source of the discharge.

Christchurch West Melton zone delivery lead Nathan Dougherty said the incident is a high priority, with several staff working full-time on it.

“We don’t yet have an answer as to the suspected source or nature of the discharge,” he said.

“We have taken fish and water samples for testing, however, it is proving complex to narrow down exactly what we are testing for. Additionally, tidal influence has made it difficult to identify the potential ‘injection point’.”

The team has been on site visiting businesses in the area, looking for links to the incident. An oil absorbent boom has been installed, and an oil barrier boom at a major stormwater outfall to the Heathcote River.

A clean-up of the area is happening today, with dead fish being removed and disposed of. At the same time, the team will be looking for evidence of any freshly deceased fish.

The public advice remains to stay clear of 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 into contact with the water, keep dogs away, and don’t eat fish from the area.

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