Waikato Regional Council staff are checking an old mine shaft in the Karangahake Gorge this morning for the liklihood that it is the source of discolouration of the Ohinemuri River yesterday afternoon.

Regional Compliance Manager Patrick Lynch says staff will check to see if the shaft is the source and whether it is continuing to discharge sediment into the environment.

The council is also tracking the plume of discolouration in the river, and has been estimated it is likely to reach the Firth of Thames between 9am and 10am this morning.

“Efforts are being made to understand what the plume looks like now, and what the effects may be on the river and the Firth of Thames.”

Yesterday, Waikato Regional Council urged people to treat the bright orange discolouration of the Ohinemuri River as contaminated.

The incident was reported to the council at about 3pm.

The council will update information as it becomes available.

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