Bartholomew Run enters the Olentangy River at RM 14.48. It is 1.3 miles in length and drains approximately 4 square miles in Delaware County. The Ohio EPA monitored this tributary in 1999 at Bennett Rd. (RM 1.0 and 0.70). EPA water quality assessments are based on the chemical, physical, and biological integrity of the river. This tributary is listed as "non-attaining" for a warm water habitat. One of the main reasons for this classification is bank erosion from development. Lack of adequate vegetative cover along the banks is also an issue. Increasing the amount of vegetation will not only improve stream habitat, but also help to stabilize stream banks.