a chemical standpoint, Roaring Creek is infertile. The specific conductance of Roraing Creek ranges from 11 micro-siemens per centimeter at site 2 to 127 micro-siemens per centimeter at site 4. In 2003 and 2004, the pH of the creek ranged from 7.0 to 7.2. In a later survey, it was found to be acidic at sites 1 and 2 (6.50 and 6.89, respectively), but alkaline at sites 3 and 4 (7.34 and 8.27, respectively). The concentration of alkalinity in the creek ranges from 5.1 milligrams per liter at site 1 to 32 milligrams per liter at site 2. The concentration of water hardness ranges from 28 milligrams per liter at river mile 4.04 to 44 milligrams per liter at river mile 8.54. The discharge of the creek is 12.2 liters per second at site 1, 243.5 liters per second at site 2, 216.7 liters per second at site 3, and 271.6 liters per second at site 4. The concentration of nitrogen in Roaring Creek ranges from 956.5 micrograms per liter at site 1 to 2343.1 micrograms per liter at site 2. The phosphorus concentration ranges from 12.6 micrograms per liter at site 1 to 28.6 micrograms per liter at site 2. Geography, geology, and climate The elevation near the mouth of Roaring Creek is above sea level. The elevation of the creek's source is between above sea level. From above sea level, the gradient of the creek is 57.1 feet per mile. From above sea level to its mouth, the gradient is 25.7 feet per mile. The topography at the headwaters of Roaring Creek is mountainous. However, much of the watershed is rough and hilly and the creek flows through a valley surrounded by broken hills. It flows through a narrow gorge for its last . The creek's channel is sinuous. There are cobbly and rocky rapids on some reaches of the creek. In the gorge, the creek flows past cliffs and over ledges and waterfalls. A set of wet limestone ledges known as the Roaring Creek Bluffs are located along the creek in Franklin Township and Montour County. Power lines also cross the creek in this reach. Some strainers occur on the creek upstream of State Route 3012. A ridge known as Sharp Ridge is located near the creek. Roaring Creek is located in the ridge and valley physiographic province. A dividing ridge separates the creek from the Susquehanna