Large digital billboards could be turned off late at night under a proposal by Melbourne city council to crack down on light pollution and reduce its health and environmental impacts.
A review, commissioned by the council, recommended the introduction of a curfew for illuminated signs above ground level.
It comes amid growing research into the impact of light pollution on sleep and circadian rhythms.
The Greens councillor Rohan Leppert, Melbourne city council’s planning lead, said it was reasonable to consider powers to ensure the effects of bright lights could be reduced.
“Just as we turn noise off through local laws before 7am, we don’t want a situation where signs are so bright when no one is watching them – but they have the capacity to keep people awake,” he said.
The review recommended the council create location-specific lighting requirements for three “signage areas” – the capital city zone (which includes the central business district); Docklands, commercial 1 & 2 and industrial areas; and mixed-use areas residential areas.
The review proposed banning above-ground illuminated signage between midnight and sunrise on Monday to Thursday nights, and 1am to sunrise on other days.
The curfew would be implemented within Melbourne’s capital city zoned areas to minimise the impact of artificial light at night in the city.
“In all other areas of the city where pedestrian activity at night is even lower, then the above-ground illuminated signage should be switched off between 11pm and sunrise throughout the week,” the review said.
“Business identification signage in all areas where the premises are open would be exempt.”
The report said artificial night-time light affected individuals differently, with some people more susceptible to its effect of suppressing the hormone melatonin, which moderates sleep cycle.
It also pointed to the negative impact on biodiversity. In 2020, Australia introduced national light pollution guidelines for wildlife.
Dr Katherine Dafforn, an environmental scientist at Macquarie University, told Guardian Australia that there had been a growing body of research about the impact of light on animals over the past two decades.
“Some of the earliest work on light pollution has really come from offshore installations, where a big oil rig out in the ocean has lots of lights on, and they recognise that this has impacts on things like birds flying past and can also affect the fish and the mammal populations in the waters around,” she said.
The review said the council should also introduce “global best practice” guidelines for illuminated and electronic signs.
A report from council officers proposes changes to its planning scheme based on the review, which was completed last month by consultants Hodyl and Co.
The review found illuminated signs had increased artificial light at night in the municipality and were detrimental to the city’s liveability and sustainability.
Leppert said it had been more than 20 years since the council’s signage policy was reviewed.
“In that time, the technology has changed significantly, and our understanding of the effects of unnecessary light on human health, biodiversity and safety has changed quite a lot,” he said.
“The type of signs we’re seeing more and more of are the electronic signs. These are signs that can be more distracting than straightforward, backlit or floodlit signs.”
The report’s recommendations will be considered at council’s Future Melbourne Committee meeting on Tuesday.