In a New Zealand first, two jet-turbine-powered boats will run head to head in the Waitaki River Race, part of the southern circuit.
Race organiser Peter Templeton said two open-class boats powered by helicopter jet-turbine engines and capable of reaching 200kmh were among the 17 entries received.
The field will include two from the North Island, The jet-turbine entries are New Zealand jet-boat marathon champion John Derry (Blenheim) and Duncan Storrier (Ashburton) in his first race outing.
Their boats' engines produce a huge 1325kW - significantly more than a Formula One racing car.
This year, the start of the event has been switched to Bill Pile's property on MacPherson's Rd on the south side of the river, flooding having affected the ramp on the south side of the river below the SH 1 bridge and north side at the end of Te Maiharoa Rd.
The event starts at 10am with the upstream leg, the fastest boats able to complete the leg in between 25min and 30min, to finish at Kurow.
The island between the twin bridges at Kurow is the best place for spectators, with a sau-sage sizzle and short event around the island starting at 12.30pm.
The down-river race starts at 2.30pm.
Mr Templeton said scrutineering before the race start would be on Friday night at the Armada Motor Inn in Oamaru and Saturday morning at the weigh bridge at Waitaki Bridge on SH1.
