BEDDING PLANE CONTROL OF KARST GROUNDWATER FLOW IN SOUTHWESTERN MISSOURI DETERMINED BY DYE-TRACING STUDIES

Population growth and development in southwestern Missouri have stressed the water resources of the region. Springfield, Missouri's third largest city, is surrounded by a number of rapidly growing smaller towns. A rural area west and northwest of Springfield lies in the midst of this growth, between three of these small towns and adjacent to the Springfield-Branson National Airport. Much of this rural area spans a surface water divide and the karst groundwater basins have not been well-defined. A major interstate highway and railroad line also cross this portion of Greene County.

To investigate groundwater flow in the Clear Creek area of northwestern Greene County, dye-tracing studies were undertaken in an area of groundwater divide uncertainty remaining from historic research work in the 1970's and 1980's. Combined with local field observations and cave studies, the results of these dye traces suggest that bedding planes or similar stratigraphic features play a significant role in the direction of groundwater flow. Supplementing the bedding plane control, limited impacts of fracture traces were observed in the dye tracing results. A review of the historic and recent data will be presented along with plans for future investigations to better understand geologic controls on the southwestern Missouri karst flow system. The results of these studies will offer important insights into the local groundwater flow system in the event of contamination.