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{The Following discussion is based upon the US Geological Survey's Techniques of Water - <br />Resources Investigations Series, Book 4: Hydrologic Analysis and Interpretation, Chapter 43: <br />Statistical Methods in Water Resources (Chapter 3: Describing Uncertainty) by D.R. Helsel and <br />R. M. Hirsch. This technical reference provides the scientific background and guidance <br />important to the systematic interpretation of hydrologic data. The document is available online <br />and is a valuable aid to understanding and interpreting the analyses described here.) <br />The next step in producing a representation of the discharge at Middle Creek - Upper above the <br />LT was to compute the Geometric Mean of the area- prorated data values from the Greenhorn <br />Creek near Rye, CO Hydrograph. This step is of value because of the inherent statistical <br />weaknesses found in any collection of data intended to measure natural stream discharge. <br />Without getting into the details of statistical theory, it is worth noting that a set of discharge <br />measurements is inherently inaccurate, no matter how well collected, due to the difficulties <br />attendant to data collection, especially hydrologic data. In this particular case, the short period of <br />record lends even greater merit to the use of this statistical tool. To give deference to this fact <br />and to increase the value of the hydrograph product of this analysis, the Geometric Means of the <br />data were computed and plotted along with the 95% Confidence Intervals about the data. The <br />resultant hydrograph, including recommended Instream Flow values, is displayed in Figure 1 <br />with the data displayed in Table 2. <br />5 <br />