Emergency crews are investigating the source of a leak of an unknown substance into Swan Creek in South Toledo.
Crews from the Toledo Fire & Rescue Department responded to Swan Creek Preserve Metropark Friday morning on a report of an oily substance in the water.
It appears to be coming from Heilman ditch, a small tributary that empties into Swan Creek near the 4200 block of Glendale, according to Scott Carpenter, director of public relations for the Metroparks…