Alexander, Scott CAlexander Jr., E. Calvin2017-03-032017-03-031997-07-23https://hdl.handle.net/11299/184784S.J. Louis Construction, Inc. as part of their S.A.P. 23-644-03 Fillmore County project authorized in a letter dated June 5, 1997 dye traces of three of the sinkholes along the eastern segment of County Road 44 in Fillmore County. A collaborative trace between the University of Minnesota and the Minnesota Department of Natural Resources.On June 6 1997, three dye traces were initiated from sinkholes D6741, D6742, and D6743 which are located on the north edge of Highway 44. The sinkholes are 2.23, 1.28, and 0.38 miles west of Highway 44's junction with Minn. Highway 139 on the south edge of Harmony Minn. Flow from sinkholes D6741 and D6742 resurged at Odessa Spring in four to six days. Odessa Spring is on the Upper Iowa River about 3.5 miles southwest of that segment of Highway 44. The third dye washed into sinkhole D6743 was not detected as any of the monitoring sites as of July 8, 1997. None of the dyes were detected in the upper or lower underground streams in Niagara Cave.enDye TracingDye TraceKarstSpringsSinkholeFluorescentDyeSpringshedSinking StreamPseudokarstReport