Maitland Triathlon organisers monitoring Hunter River for swim leg

Paul Humphreys of H events said the event will become a cycle and run only if the river is unsafe for swimming, but he isn't to worried that will be the case.

"Fingers crossed we don't get much more rain and the river is calm so we'll be able to swim," he said.

A final decision about the conditions of the river will be made next Wednesday.

Humphreys said they were expecting between 400 to 500 competitors in this year's Quarry Mining Maitland Triathlon, including local upcoming athletes Liam and Monty Dixon from Maitland Triathlon Club.

The event has drawn triathletes from far and wide as it is one of the qualifying events for the Age Group World Championships.

"We're one of the events where they can come and compete for a qualifying spot," Humphreys said.

The long distance event will kick off at 6.45am, followed by the Olympic distance at 7.05am and the sprint distance at 7.25am.

Participants competing in the long distance event will swim 2km, cycle 60km and run 15 kilometres. The Olympic distance is 1.5km swim, 40km cycle and 10km run, while the sprint is 750m swim, 20km cycle and 5km run.

Participants will swim in the Hunter River, cycle a 20km looped course heading through Morpeth and into farmland towards Duckenfield and run a 2.5km looped track.

Spectators can enjoy the event from the riverbank or from the comfort of one of Morpeth's cafes on Swan Street.

"They get a pretty good view of the event while enjoying a coffee," Humphreys said.

Road closures on the day will be in place to ensure the safety of participants, spectators and road users.