Inquest into NSW waste centre drowning

An inquest into the drowning death of a Sydney waste management centre employee has heard he told a colleague "don't do what I'm about to do" before being sucked down a drain.

Father of three Paul Smith, 43, died in March 2014 while trying to clear debris from a pipe at a Lucas Heights waste facility during torrential rain.

Deputy state coroner Hugh Dillon is investigating policies around unblocking drains at the south Sydney site, and procedures on stopping work in severe weather, to understand if anything can be done to prevent similar deaths in the future.

Counsel assisting the coroner, Bronwyn Lorenc, said Mr Smith was described as an exceptional swimmer and known by his colleagues to be a very safe worker.

"The brief of evidence suggests that at the time of Paul's death, the process of unblocking the drains at the site was not considered hazardous and workers were unaware of the possible suction effects at play," Ms Lorenc told Glebe Coroner's Court on Tuesday.

The inquest heard staff at the site regularly cleared drains to prevent breaking environmental rules.

Water that ran off green waste processed at the site was to be kept separate from stormwater, and there were penalties if this did not occur.

Ms Lorenc said Mr Smith, who was employed as a supervisor at the Sita facility having worked with the company since 2011, had attempted to unblock a drain while water levels were reportedly up to his stomach.

The court heard the standing position at the Lucas Heights site was for staff not to enter floodwaters above gumboot height.

He handed a colleague his wallet and phone and entered the water to remove the blockage.

"After initially attempting to remove the blockage with his hands, Paul was seen to use his feet to kick at the drain," she said.

His legs were sucked into the drainpipe and, despite rescue efforts, he drowned.

Ms Lorenc said at the time of Mr Smith's death, an emergency response plan at the organics facility included provisions on flooding and severe storms.

Both situations were considered "code brown" emergencies requiring all work at the site to be moved indoors if declared.

The coroner will be asked to consider whether a "code brown" should have been declared on the day Mr Smith died.

The inquest is expected to run until Friday and hear evidence from a number of witnesses.