Noticed anything different about the Brisbane River as of late?

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Local residents on discussion website Reddit have been sharing photos over the past few days of what appears to be a river not as brown as we're accustomed to seeing.

ABC Brisbane put the question to its Facebook followers, with many agreeing they too thought the river had been looking clearer this past week.

So what's going on?

Well you'll be happy to know your eyes do not deceive you — the city's famed "brown snake" has been lacking its usual muddy colour of late due to the lack of rain, experts say.

Healthy Land and Water principal scientist Dr Paul Maxwell said the colour of the Brisbane River fluctuated throughout the year, primarily based on the amount of rainfall runoff in the region.

"It is not unusual for the river to appear clearer following a period of low rainfall," he said.

"The Brisbane River gets its brown colour from the mud and soil, or sediment, that has been washed into the river.

"When it rains, the water flows over the land and picks up sediment and transports it into creeks and waterways, ultimately ending up in the Brisbane River and Moreton Bay.

"When the rain stays away, the flow of stormwater and sediment stops and sediment already in the water settles on the banks of the river. As a result, the river appears clearer.

"If the summer rains hit the region over the next few weeks, the river will return to its typical brown colour," he said.

Dr Maxwell said reducing stormwater runoff in urban catchments, reducing erosion in the upper catchments and building resilience into south-east Queensland's waterways was the best way to improve the health, and colour, of the Brisbane River.

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"Healthy Land and Water is hard at work on several projects aimed at reducing the flow of sediment into our waterways."

Australian Rivers Institute director Professor Stuart Bunn echoed Dr Maxwell's statement.

"The catchments are in such a state that every time you get a major rain event, particularly in catchments around upper Brisbane, all that material ends up in the main channel," Professor Bunn said.

"You get a little bit of run off from construction sites, if you've got big areas being developed for urban development, if people aren't doing the right job in terms of reducing the run off.

"But by and large it's the big rain events and catchments at the back of Brisbane that dictate water quality in the Brisbane River."

A Curious Brisbane investigation last month looked into the very popular question of "Why is the Brisbane River brown and not blue?"