The discharge of Fester Hollow in its lower reaches ranges from 0.75 to 34 cubic feet per second. The median discharge of the stream is 3.54 cubic feet per second. The minimum water temperature in the stream is and the maximum temperature is. The median temperature is. The stream's water temperature is often higher than the maximum required temperature for a stream to be considered a cold-water fishery. The median electrical conductivity of Fester Hollow is 89 milli-siemens. The highest recorded electrical conductivity is 351 milli-siemens and the lowest recorded electrical conductivity is 69 milli-siemens. The minimum pH of Fester Hollow is 7.06 and the median pH is 7.66. The maximum pH of the stream is 9.17, making it the most alkaline stream in the watershed of Briar Creek. The total concentration of dissolved solids in Fester Hollow ranges from 34 to 169 parts per million. The median concentration is 44 parts per million. The stream also has higher-than-ideal concentrations of nitrates. The watershed of Fester Hollow is in Pennsylvania's Climate Division #5. In 2012, the Briar Creek Association for Watershed Solutions performed a visual assessment of Fester Hollow, rating it for various qualities, including streambank stability and the quality of the riparian buffer. The creek was rated as 5.4 out of 10, indicating "poor" water quality.
Geology and geography
The bedrock in the southern tip of the Fester Hollow watershed consists of calcareous shale and a small amount of limestone. North of this is a band of shale bedrock. The northern and central parts of the watershed have siltstone as their bedrock. The Zipp Series, a siltloam soil, is found on the lower reaches of the stream. Fester Hollow is in the ridge and valleygeographical region of the Appalachian Mountains. There are forested ravines in along the stream. The lower reaches of Fester Hollow are at an elevation of above sea level.
Watershed
Most of the watershed of Fester Hollow is located in North Centre Township. However, the northeastern corner of the watershed is in Briar Creek Township. Major roads in the watershed include Mountain Road and Pennsylvania Route 93. The stream's watershed has an area of 4.54 square miles.
Biology
Wild trout reproduce along the entire length of Fester Hollow. Forest corridors on Fester Hollow connect to the forests on Knob Mountain.