Members of conservation groups are worried about the effect of stormwater runoff on Lake Superior.

About two dozen people attended a meeting at Prince Arthur's Landing in Thunder Bay on Monday night, hosted by the North Shore Remedial Action Plan.

They were concerned about what's in the water running off the streets and ending up in the lake, especially after a rainfall.

International Joint Commission scientist Matthew Child says contaminants like oil, grease and brake dust show up in water samples from Thunder Bay area rivers that flow into Lake Superior (Jeff Walters/CBC )

"You know, oils and greases and brake dust and all of the other things that accompany urban areas," said Matthew Child, a scientist with the International Joint Commission. "You're seeing a lot of those contaminants showing up in water samples."

Those samples were taken from rivers and creeks in the Thunder Bay area. That worries Tom Whalley from the NorthShore Steelhead Association.

"All of these streams are utilized for stormwater drainage," he said. "We have storm sewers that drain into each one of those waterways and we're very concerned with the quality of water."

Whalley added he wanted to create better fish habitat.

So does Dave Crawford, who came from Nipigon to attend the meeting at Prince Arthur's Landing.

"The small fish that are abundant in the harbour and all that kind of stuff could be impacted," he said. "The big fish eat small fish, and we want the fishery to keep going."

The meeting focused on how to reduce runoff to slow contaminants from getting into the water. Proposed solutions included creating more green roofs, planting trees and using rain barrels.

Besides improving water quality, Crawford said he hoped reducing stormwater would minimize damage from flooding.