Why doesnt NAWQA typically use historical data or data from other agencies? Were historical data and data from other agencies used in the Great and Little Miami study?
NAWQA samples are collected by strict procedures and analyzed with specific methods. The USGS typically does not use water-quality data from other agencies in NAWQA studies because the procedures used to collect samples and methods used to analyze the samples are unknown or different from NAWQA protocols and would limit our ability to compare data from one NAWQA Study Unit to another. For example, raw, untreated water samples are almost always collected by NAWQA studies; however, other agencies often collect and analyze treated water, so the data would not be usable for NAWQA studies. In this study, however, existing ecological data were gathered from the Ohio Environmental Protection Agency (Ohio EPA) Division of Surface WaterMonitoring and Assessment Section and the Indiana Department of Natural Resources prior to fish sampling to identify all fish species known or expected to occur in the Study Unit; such data can be helpful with the identification of problematic species, new specie
