Mysterious humming noise in Sydney's west leaves residents unable to sleep

For over a month, residents in Rydalmere in Sydney's west have been experiencing sleepless nights due to a humming noise at all hours.

The noise, which has been found to be coming from an industrial precinct in Camellia, is also affecting residents up to three kilometres away in Ermington.

"I'm not getting any sleep, I'm waking up at two and three in the morning," a resident said.

READ MORE: Albanese splits from Trump on key issues hours after smiling selfie

"It sounds like a drone sitting above your house."

9News can reveal that following an overwhelming number of complaints, the Environment Protection Authority (EPA) requested that industrial premises, Heidelberg Materials, Knauf, and James Hardie inspect their facilities and equipment.

Initially, Metro West tunnelling and late-night drone activity by NSW Police were suspected of causing the noise, but they were ruled out by the City of Parramatta Council and the EPA.

The EPA gave the businesses until today to determine which site the noise is coming from, however, none of them have claimed to have found a problem yet.

READ MORE: Macquarie to repay Shield investors $321 million over failure of superannuation fund

The EPA says it believes it's on the right track and will deploy noise monitoring equipment and may request independent inspections on all three sites.

It admits, however, that the process could take weeks.

"If we identify the cause of this was preventable, then we have powers under legislation to throw the book at them," said an EPA spokesperson.

"I'd just like to see it stop. It's not just a small selection of people, it's a great number of people that have been affected by it," a resident said.

DOWNLOAD THE 9NEWS APP: Stay across all the latest in breaking news, sport, politics and the weather via our news app and get notifications sent straight to your smartphone. Available on the Apple App Store and Google Play.