River Rescue responded to a call for some type of substance creating a slick or sheen on the Allegheny River just before 1 p.m. The call was first reported by someone looking down at the river from the 48th floor of the U.S. Steel Tower.

It was detected on the left bank of the Allegheny if a craft was traveling downstream. The sheen was described as splotchy, rather than a constant slick and it was spotted from around the Sixth Street bridge up to about a quarter mile past the 62nd Street bridge, where it began to dissipate.

River Rescue turned its boat back around at the 62nd Street bridge as the water also became too shallow for them to continue their search for a source, which they were unable to detect.

They will be reporting their findings to the Coast Guard and the EPA .

Any updates will be added to the blotter.