The Granite Creek Watershed is roughly 50 square miles in size and includes two lakes and nine named creeks totaling approximately 60 linear miles. The boundary of the watershed is formed by the Sierra Prieta and Bradshaw mountain ranges.

Land use in the watershed is diverse; the creeks’ headwaters reside in the Prescott National Forest, run through grasslands, and then through urban areas of the City of Prescott. In 2008 Prescott’s population was estimated at 43,280 residents.

In 2004, Arizona’s 303(d) List of impaired waters (waters not attaining their water quality standards) listed two water bodies in the Upper Granite Creek Watershed: Watson Lake and Granite Creek. Watson Lake was listed as impaired for low dissolved oxygen, high pH, and high nutrient levels. Granite Creek was listed as impaired for low dissolved oxygen. Although neither water body is presently impaired for E. coli, testing of bacteria levels in both bodies have consistently exceeded state water quality standards.