Nicholas Allmendinger, Geology program, Western Carolina University

	The Cullowhee Creek Stream Enhancement Project - is funded by a land development company to receive mitigation credit for some development related disturbance in southern Jackson County. Buck Engineering was hired to develop a new golf course in the Highlands region of Jackson County and since that project involved environmental disturbance along a stream, they needed to improve the condition of some other stressed stream system elsewhere in the region. The enhancement of Cullowhee Creek on the campus of Western Carolina University will attempt to improve upon many of the streams functions which have been impeded during recent decades by substantial development within the watershed. Such functions in the stream channel include improving bank stability
	and both sediment and water discharge. The developers hope to achieve these goals by installing three types of rock structures at critical points along the stream.
		Prior to the current enhancement project, there have been several other engineering projects along Cullowhee Creek. Throughout the campus reach, there are a number of weirs that may have been originally installed to improve fish habitat (Cullowhee Creek is a hatchery supported stream). There have also been previous attempts at bank stabilization that include the installation of rip rap, and shrubby vegetation. Through the years, weirs like the one pictured here have collected a large amount of sand in their impoundments, filling in pools in the bed which are an important component of fish habitat, and causing the evolution of planar beds in some of the downstream reaches.
	Riprap in the banks (the large boulders along the left bank in this picture) was probably installed to prevent the stream from migrating laterally. The university has a great deal of important infrastructure (The Ramsey Center, Catamount Road, sewer and water lines, freshman parking lots, etc.) in close proximity to the stream, making it important that bank erosion be kept to a minimum over much of the length of the creek. In places where erosion is less severe, shrubby vegetation has been planted on the banks with or without rip rap to reduce the velocity of the water during peak discharge events (floods for readers in New Jersey). Notice also, that the riparian zone of Cullowhee Creek is highly manicured. Keith Tyburski is standing on a freshly mown grassy surface that would probably be forested in a natural stream system. The bare patches to his left are sand deposits
	left behind by hurricane Ivan which caused extensive flooding during the fall semester of 2004. You can glean from that information that the stream has somewhat regular access to it's floodplain where it is low in elevation (where Keith is standing) but may not where it is significantly higher (the opposite bank).
		There are three types of structures that are being installed along Cullowhee Creek, but one type is predominant: the cross vain. This structure is shaped like a capital letter 'A' that points upstream. Water in the stream is drawn away from the banks when a cross-vain is encountered, and is forced to the center of the channel. Since much of the streams energy is concentrated in the center as well, these structures should have the long-term effect of reducing bank erosion, and inspiring an increase in bed erosion between the two limbs of the letter 'A'. The cross-piece in the letter 'A' has not yet been installed in this structure but, when it is, it should dissipate a significant part of the streams energy, thereby limiting the downstream extent of pool growth.
	Here are two pictures of Cullowhee Creek from the same bridge at a fairly high stage. The picture on the left was taken during the fall semester of 2004 (before work on the enhancement project began), while the picture on the right was taken during the summer of 2005. In the background of the picture on the right, the newly installed cross-vain can be seen deflecting flow toward the middle of the channel.
	In addition to the boulder structures, the enhancement project also includes a more direct approach toward bank stabilization in some critical locations. Just upstream from the campus picnic pavilion there is a well-scoured bank on the inside of a channel bend. The developers have "re-graded" this bank by removing sediment from the upper portion of the over-steepened slope. This will reduce the potential of catastrophic bank failure which could add
	large amounts of sediment to the channel. They have also spread burlap on the banks to support the growth of grassy vegetation which will improve the long-term stability of the bank.