The event had aimed to utilise a 250 metre stretch of the river, starting from Sawyer Park and swimming toward the ANZAC Centenary Bridge.

It is the first time the event has been cancelled in its 20-year history. It was scheduled to run on Saturday, February 8.

Tournament organiser Mark Pumpa said it was a difficult decision to make.

"I'm very disappointed. It's been like a baby for me for the last 20 years, watching it grow and progress," he said.

"Seeing the kids come through and where they have gone to, and local people like Kelly Miller; she started at the Horsham Triathlon and now she has competed all over in the biggest Ironman events in the world.

"We just don't want to lose that. We want to keep offering the event for as long as we can."

Previously, when the Wimmera River was low ahead of the event, the triathlon had used the Horsham Aquatic Centre pool for the swimming leg of the competition.

Mr Pumpa said the pool could not be used this year due to scheduling conflicts with an annual swimming carnival.

"It was just a duty of care. We decided if we pull the pin now, it's better than doing it in another two weeks time, if the water has decreased further or some algae has formed in the river," he said.

"It is low at the moment with the hot days that we've had, and we've got some more on the way, so it was a decision that we really had to make now. We couldn't just wait and make it in two weeks time.

"It's a decision that wasn't made lightly."

Mr Pumpa said Tri Horsham would consider rescheduling the event to later in the year for future editions.

"We might look at changing the date to maybe March, the weekend before or after the Labor Day long weekend, because there seems to be enough water through the river for the fishing comp," he said.

"Hopefully we will be back next year bigger and better."

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