Little Topashaw Creek - Nutrient TMDL's - Introduction
Surface water quality degradation in north Mississippi hill land stream watersheds has been emphasized as a problem within ecoregion IX (southeastern temperate forested plains and hills). Little Topashaw Creek, a fourth-order stream in the Yalobusha River watershed of the Yazoo drainage basin, is a highly eroded hill land stream typical of the region with eroding banks frequently invading adjacent agricultural fields. A 2 km reach of the Creek is currently being rehabilitated using large woody debris structures and selected plant materials to stabilize channel incision and bank erosion. In conjunction with this rehabilitation, intensive monitoring of water quality is performed. Such information is useful in determining total maximum daily loads (TMDLs) within the Yazoo basin. TMDLs are based upon the total daily amount of material in a body of water from natural, point and non-point sources (including a margin of safety) that would not have a deleterious effect on aquatic life. The purpose of this study was to examine nutrient concentrations in Little Topashaw Creek and evaluate the appropriateness of currently proposed USEPA ecoregion IX nutrient guidelines are for this region.