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CHRISTCHURCH - Maritime New Zealand (MNZ) is investigating a dinner river cruise in Blenheim on Saturday night that left 11 people ill with carbon monoxide poisoning.
One person was admitted to Wairau Hospital overnight and 10 people were treated and discharged after the incident aboard Marlborough's River Queen tourist boat.
A Nelson-Marlborough District Health Board spokeswoman said the 11 were suffering varying symptoms of nausea and headaches typical of carbon monoxide poisoning.
All but one of those affected were discharged on Saturday night, with the remaining patient leaving hospital yesterday morning.
Fumes from the replica paddle-wheeler's twin outboard engines leaking into the boat's main cabin were blamed for the incident.
An MNZ spokesman confirmed today an investigation was under way. No further details were available.
River Queen owner Peter Makin told NZPA the incident was a "freak situation" which staff handled immediately.
A low tide and calm conditions on the Opawa River on Saturday night meant fumes from the River Queen's outboard motors kept pace with the boat, gradually building up inside the lower deck cabin.
Mr Makin said it was only when passengers went downstairs as the boat returned to the dock that people started feeling ill and the problem became apparent.
"Everyone was having a great time and it was horrible for the evening to end like that," he said.
He arranged for the affected passengers to be ferried to hospital as a precaution, suspended operations immediately and notified MNZ.
Mr Makin said marine surveyors this morning had recommended the engine compartment be sealed and an extraction fan installed. Modifications were expected to be completed for trials on Thursday.
- NZPA
