The source of Coal Creek is 1,400 feet (425 m) above sea level on Cougar Mountain.

It flows approximately 7 miles (11 km) to the northwest, emptying into Lake Washington at Newport Shores.

[4][5] In 1987, King County and the City of Bellevue produced a hydrological model and subsequent watershed management plan for the creek.

The earlier mining activity included mine tailings dumped along the stream bank, creating steep slopes which would collapse and create landslides, contributed to "extensive sedimentation problems" in Coal Creek.

[7] As part of the Bellevue city watershed management plan,[8] Coal Creek salmon escapement is monitored annually.