Connoquenessing Creek Watershed Conservation Plan - Western ...

Connoquenessing Creek Watershed Conservation PlanChapter 3. Water ResourcesTable 3-1. Major TributariesTributary% AreaDrainage Area(square miles)Upper Connoquenessing Creek 136.43Thorn Run 1.63 7.69Bonnie Brook 4.33 20.44Middle Connoquenessing Creek 147.99Thorn Creek 8.95 42.22Glade Run 8.65 40.79Breakneck Creek 8.83 41.64Lower Connoquenessing Creek 187.21Little Connoquenessing Creek 13.67 64.49Camp Run 3.14 14.80Brush Creek 11.89 56.10Slippery Rock Creek (subwatershed) 366.12Important Components of Water ResourcesHydrologic CycleIn order to understand the components of water resources within the watershed, one must firstunderstand the hydrologic cycle, or the cycle of water. The continuous cycle consists of five basicprocesses: condensation, precipitation, infiltration, runoff, and evapotranspiration or evaporation. As airtemperature drops, water vapor in the air condenses to a liquid, forming clouds in the atmosphere.Precipitation occurs when the clouds can no longer hold the moisture within them. Precipitation reachesthe surface of the Earth and may be contributed directly to a body of surface water, infiltrate into theground contributing to groundwater, evaporate back into the atmosphere, or run off the land into a surfacewaterbody. If precipitation occurs faster than the water can infiltrate a particular surface or if the surfaceis impermeable, the water will shed off the land or surface as runoff into streams, lakes, or other surfacewaters. Simultaneously, water may evaporate (the change of liquid to vapor) directly from the surface orbe taken up by plants, transpired, and evaporated back into the atmosphere where the process ofcondensation occurs; and the cycle continues.GroundwaterWater that seeps into the ground and is stored beneath the land surface in pores and openings of soiland rock formations is referred to as groundwater. Although groundwater is commonly considered aseparate entity from surface water found in streams and lakes, the two are constantly interchanging andare actually a single resource. In fact, the majority of freshwater in Pennsylvania is found underground,and that groundwater supplies wells, streams, and reservoirs on which we depend for drinking water,industries, and other necessities of life.Groundwater moves with the forces of gravity. It may move through the earth until it emerges at thesurface as a discharge (springs or seeps) or is stored within areas of rock and soil, called aquifers.Groundwater discharge is a major contributor to surface waters. The average percentage of stream flowfrom groundwater is around 60–70 percent. Therefore, stream flow and surface water availability isheavily dependent on the quantity of groundwater. As a result of this dynamic, the quality of streams andlakes can be directly impacted by the quality of groundwater (Fleeger, 1999).3-3