Submitted to: Missouri Academy of Science Transaction
Publication Type: Abstract Only
Publication Acceptance Date: February 27, 2004
Publication Date: April 22, 2004
Citation: Lerch, R.N. 2004. Water quality monitoring in two karst watersheds of Boone County, Missouri [abstract]. Missouri Academy of Science Transaction. p. 55. Technical Abstract: Karst watersheds with significant losing stream reaches represent a particularly vulnerable setting for ground water contamination because of the direct connection to surface water. Due to existing agricultural land-use and future urban development pressures, two losing stream karst watersheds were chosen for intensive monitoring in Boone County, MO: Hunters Cave and Devils Icebox Cave. Year-round monitoring was conducted from April, 1999 to April, 2002 with the objective of characterizing the water quality status of the main cave streams relative to herbicide, nutrient, and bacterial contamination. Herbicides were frequently detected in both cave streams at very low levels (e.g., <0.1 ppb), but higher levels (>1 ppb) were observed in runoff events each spring. Nitrogen and phosphorus concentrations in both caves were generally much higher than EPA guidelines for nutrient contamination of streams, and the Icebox had consistently higher levels of both nutrients than Hunters Cave. Fecal coliform bacteria levels were generally above the whole body contact standard (200 cfu/100 mL) in the Icebox, regardless of flow conditions. Under runoff conditions, fecal coliform levels in both caves can exceed 10,000 cfu/100 mL. Fecal coliform levels were significantly correlated to turbidity, indicating transport primarily occurs via sorption to suspended sediment. Current management efforts should focus on implementing BMPs to reduce contaminant transport from row cropped fields and rangelands. Future management considerations for these watersheds are focusing on impending urbanization, and the development of a comprehensive watershed land-use plan. Education efforts will continue to stress that cave systems are directly affected by surface land-use activities.