ABSTRACT
This paper summarizes the methods and results of a ground water dye tracing study conducted as part of an underground drainage assessment project for the Indiana Department of Transportation, State Route 37 Bedford to Mitchell highway improvement project. Semiquantitative dye tracing involved injection of water soluble, low-toxicity fluorescent dyes into fifteen sinkholes along the highway right-of-way. The dyes were successfully traced to resurgence points at three karst springs (Pless Cave, Blue Spring Cave and Hamer Cave). The data from the study indicate that the project alignment traverses at least three ground water drainage basins. Dye tracing results in the Pless Cave Spring and Blue Spring ground water basins are consistent with downdip or strike oriented ground water flow through cavern systems beneath the Mitchell Plain. Dye tracing to Hamer Spring was found to be in an eastward (apparent updip) direction, making it the longest ground water tracing conducted in the Indiana karst in a direction opposite to regional dip.
