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• 10 <br />runoff volume to peak discharge. The equations were also developed for rio ranges <br />of drainage areas: equal to or less than three square miles; and from three square <br />miles to 15 square miles. Thus, one set of equations is applied to the Magpie <br />and Tipple area drainage with areas less than three square miles and one set to <br />~ the Newlin drainage between three and 15 square miles. The equations were given <br />for the 10-, 25-, 50-, and 100-year events. Again, the 2-year event was obtained <br />from a logarithmic-probability plot of the 10-, 25-, 50-, and 100-year events. <br />The resulting peak discharge for each area and event is given in Table 2. The <br />C same areas as presented in Table 1 apply. The equations used are given in the <br />subscript of Table 2. Also presented in Table Z are the volumes for each event <br />r estimated using the regression relating volume to peak discharge. These results <br />are lover than those estimated by TM-1. Because the second method used is spe- <br />• cifically for small rural watersheds in the Arkansas River basin, the results <br />from this method will be weighted more heavily than the results from TM-1 in <br />comparison with and calibration of the NULTSED program results. <br />2.3.2 Runoff Due to Snowmelt <br />The method used to estimate the snowmelt runoff is described in the EPA <br />publication "An Approach to water Resources Evaluation of Non-Point Silvicultural <br />Sources' (a procedural handbook). In this publication, a method for estimating <br />the baseline hydrograph due to snowmelt runoff vas developed using the "Subelpine <br />water Balance Hodel' (WATBAL) developed by Leaf and Brink (1973). Development <br />of the baseline hydrograph does not involve estimation of silvicultural activities, <br />but assumes baseline or present conditions. Two assumptions are made in the method <br />which tend to produce a conservative (high) estimate. The first assumption is <br />• that all areas within the watershed are contributing at the same time; the <br />second assumption is that snowmelt begins or starts on some assumed date. The <br />second assumption assumes that no snovmelt occurs before the selected date and <br />