The Department of Conservation is warning motorists to be careful after a 4WD vehicle carrying three Frenchmen was swamped and they were forced to sit on the roof after the driver tried to ford the swollen Arrow River on the way to Macetown.
The three men were found on top of the vehicle 5km upstream from Arrowtown just after midday on Monday, following heavy rain over Sunday night.
On Wednesday, Doc helped tow the vehicle from the river.
Doc Wakatipu biodiversity threats programme manager Mark Mawhinney said people needed to exercise caution when making their way to the popular gold mining ghost town and Doc campsite, as they faced a minimum of 10 river crossings.
"Certainly at times you need a vehicle with a snorkel and good river-crossing experience. It's not a particularly technical river to cross but once the river starts to rise - as it had on Monday - you can't see the bottom and you can get into trouble, which can be expensive," Mr Mawhinney said.
Suggested safe navigation advice was to drive in a downstream arc: "that's important because you can see the bottom," he said.
Mr Mawhinney said the Arrow River could rise and fall quickly and people intending to cross it should always "keep an eye on the forecast".
Another hazard was hydraulic-locking, when water sucked through the air intake into the cylinders could not compress, wrecking an engine.
Nomad Safaris operations manager Tony Curtis said the Macetown campground was becoming quieter after being busy for Christmas-New Year.
