Ginninderra Catchment Authority co-ordinator Damon Cusack said a recent trip to test waterways near the picturesque Ginninderra Falls revealed big clusters of plastic bottles.

"We were doing a survey on the bugs that live in the water to give us an idea of what the water is like to live in," he said.

"All of the high water areas were covered in plastic bottles."

He estimated there were hundreds of bottles at each of the 10 sites where they did testing.

"There were thousands of bottles through the gorge area," Mr Cusack said. "We see it a lot in our urban waterways so I wasn't terribly surprised.

"I probably was a bit surprised to see so many though."

A stencilling program will get under way leading into Clean Up Australia Day on March 1.

Mr Cusack said the group would work with high school and college students to spray anti-litter slogans above stormwater drains.

"It is a public awareness raising campaign to let people know that all of the drains are linked and effectively everywhere they drop a bit of plastic ends up in our wetlands and our rivers," he said.

"If we can get people to avoid throwing things down the drain then that is a good result." The volume of rubbish flowing into Canberra lakes and waterways has been an ongoing issue – floating plastics and parking tickets are two of the most common items.

"Our stormwater systems don't do a great job dealing with floating plastics," Mr Cusack said.

"Our gross pollutant traps hold them for a little while until we get a high-water event and then they flow over.

"They are not really designed for trapping most of the floating bottles."

He said he would like to see the ACT government adopt a container deposit scheme where people received 10 cents per plastic or glass bottle they collected.

Environment Minister Simon Corbell said, in January, the ACT had always supported a container deposit scheme in principle and if NSW moved to adopt one, that would be the trigger needed in Canberra.