Several dye trace studies have shown that the drainage basin of Harrison Spring is, by Indiana standards, very large. Indian Creek is a major infeeder to the Harrison Springs drainage system as the entire summer flow of Indian Creek can disappear at the Sinks of Indian Creek and re-emerge at Harrison Springs in low-flow conditions, in about one hour. Given that Big Indian Creek – upstream of the Sinks of Indian Creek – drains an area between Corydon and Georgetown, as well as Little Indian Creek (an infeeder to Big Indian) drains an area that runs east of Lanesville, the Indian Creek portion of the Harrison Spring drainage basin alone drains an area of at least .