It receives Ashelman Run and Fellow Hollow before flowing through the community of Tri Mills.

Downstream of Tri Mills, it receives Hess Hollow and continues southwest to the community of Coles Creek.

[3] Between May 2010 and July 2011, the water temperature of Coles Creek ranged from slightly under 0 °C (32 °F) to nearly 20 °C (68 °F).

The dissolved oxygen concentration in Coles Creek was also over 16 milligrams per liter in January 2011 and March 2011.

[4] The concentration of dissolved aluminum in Coles Creek is usually between 0 and 20 micrograms per liter.

The Huntley Mountain Formation consists of sandstone and siltstone and comes from the Mississippian and Devonian periods.

Additionally, there is a small patch of industrial land in the lower reaches of the creek.

[1] A fish habitat made of log cross vanes was installed in the headwaters of Coles Creek in 2012.

[4] In 2011, the habitat quality of upper Fishing Creek and its tributaries were rated on a scale of 1 to 200 (with a higher rating indicating better habitability) by Point Park University and the Fishing Creek Sportsmans' Association.

The lower reaches of the creek were given a score of 166 to 200, indicating an optimal habitat.

[4] The Pennsylvania Fish and Boat Commission has designated Coles Creek to be Class A Wild Trout Waters between its source and the mouth of Marsh Run.