Cambridge's Ashton Grey (Yamaha YZ250FX), Taupo's Nathan Tesselaar (KTM 350 XCF) and Napier's Mackenzie Wiig (KTM 300XC) rounded out the top five positions in the senior race.
The best of the senior women was Te Awamutu's Rachael Archer (Husqvarna TE150), who finished 27th overall.
A total of 77 hardy souls – 54 seniors and 23 juniors – braved the atrocious conditions, but all seemed to enjoy the race action despite the junior race being reduced from 90 minutes to one hour and the senior race being cut back from three to two-and-a-half hours.
The junior race, held earlier in the day, went right down to the wire.
The eventual winner was Cambridge rider Callum Paterson (Yamaha YZ125), with runner-up Adam Loveridge (Eltham, Husqvarna TE150) crossing the finish line just 30 seconds behind.
Napier's Bryn Codd (Yamaha YZ125), Raglan's Coby Rooks and Eltham's Josh Loveridge (Husqvarna FE250) rounded out the top five.
The best of the junior women was Palmerston North's Hannah Rushworth, the multi-talented rider who is also an international moto trials exponent finishing 21st overall against the boys on Saturday.
Round two of the New Zealand Cross-country Championships is set for farmland at Ormondville, in central Hawke's Bay, on March 18, with round three near Taupo on April 8 before it all wraps up near Mosgiel on May 12.
Only three of the four rounds are counted towards the championships, with riders to discard their one worst score, but there is a stipulation that riders attend the final round and this means the battle for national glory could last right until the final lap.