McLachlan (40) believes his six-man team has the talent to win the overall title at the event which runs from October 4 to 11, especially with its experience on natural rapids - much like the grade 4 Pacuare River they will compete on.
"A lot of the European teams don't have enough water over there in their natural rivers so most of their racing is on man-made rivers," he said.
"We're used to the big water."
The team boasts some seasoned campaigners including a former Olympic kayaker and several representatives from the national outrigger team, but McLachlan adds some serious skills to the mix.
With 40 back-to-back seasons as a rafting guide throughout Europe, North and South America, Africa, Australasia and Japan under his belt, a grade 5 rafting guide qualification - the highest commercial grade possible - and whitewater assessor, instructor and rescue technician qualifications, McLachlan is well prepared for the toughest of adversaries.
He has already competed several times at world rafting events, winning many medals with his teams in various disciplines.
With all his team-mates based in the North Island, McLachlan has prepared for Costa Rica mainly by cross-training in his outrigger canoe - waka is a sport he has competed in internationally for nearly 10 years - and kayaking, which he took up seriously this year.
He also travelled north regularly to work on the "technical stuff" with the rest of the team and trained alongside Wanaka multisport athlete Dougal Allan, who had been an "inspiration" during the tough winter months.
McLachlan's outrigger canoe was initially used as a training tool for rafting when he was not living near a river, but he has since gone on to win all but two of the dozens of long-distance waka races he has entered.
He planned to retire his canoe after Costa Rica, as the travel demands required for training and competing in waka events had become too much now he had a young family.
Rafting - a sport he had been competing in for "far too long" - could not be ruled out yet, as he had been asked to compete in a new master's division next year.
"Right when you think you're getting to the tail end, they introduce a new sport for you."
