He took a year out of the event in 2018 but showed no signs of rust as he pulled away from the field from halfway out to win yet another World Cup gold medal.
Heath, who finished with a gold and silver medal at his last World Cup regattas in 2017, praised his coach Eric Farrell for helping him stay focused and organised after he became a father last year.
He said: "It was a pretty good race. It was quite choppy out there, the wind's howling down but at least it's blowing in the right direction.
"I'm happy to start the season still in contention with the rest of the world and hopefully I'll progress through the season like in 2017.
"Last year I was focused on the K4 with the lads in the team and also becoming a father.
"Part of the process throughout that year was trying to evaluate my goals in terms of did I want to go through another cycle. Ultimately it was yes and it's how you fit everything around that.
"I've got a good idea of how much work needs to be done, it's just managing that with family life and other commitments. Luckily I've got a good coach who helps me arrange everything, so I can get the most out of training and the most out of family life."
Liam's former K2 200m partner Jon Schofield was also happy with his penultimate performance in the sport, finishing in fifth place, a mere two tenths of a second behind the bronze medal spot.
Next weekend's ICF World Cup in Duisburg will be his last as he takes up a full-time role as head of performance at the Scottish Canoe Association next month.
Elsewhere, Katie Reid qualified for the World Championship team after a seventh-place finish in the C1W 200m final while Afton Fitzhenry battled against the choppy course to finish in sixth place in the C1W 500m.
Less than an hour later, she was back in the start bucket for the B final of the C1W 200m where she finished joint sixth.
Tom Lusty, who had just 19 minutes between his B finals of the K1 500m and the K1 1000m, finished second, putting him 11th overall, and seventh, putting him 16th overall, respectively.