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f. Please rewrite introduction to this Appendix Exh. 7-14I to make it clear that the <br />model for all of Taylor Tributary Ditch (including East Taylor Ditch) varies from model for <br />East Taylor Ditch (from Technical Revision 104). <br />Response: This change has been made and page 7-141-15 is resubmitted. <br />g. The design flows in Table 1 of Appendix Exh. 7-14I appear incorrect for upper reaches. <br />Please review the design flows and correct as necessary. <br />Response: The design flows on the table were out of date based on an early SEDCAD <br />model. The design flows have been updated based on revised modeling which was done as <br />part of the Taylor Tributary Ditch contained in Exhibit 7-14C for the 100 year storm. <br />h. The page numbers for figures for Exhibit 7 -PP appear to be incorrect. They say "14PP" <br />rather than "PP." Please review the numbering and correct as necessary. <br />Response: The two figures have revised with page numbers Page 7-14-297 and 298. These <br />have been resubmitted with this change. <br />i. The collection ditches in Exhibit 7 -PP are labeled as contour ditches. This is creating <br />confusion. Please review the ditch labeling and correct as necessary. <br />Response: There does not appear to be any text labels on any of the Figures associated with <br />Exhibit 7 -PP or in the introductory text, so we assume this comment refers to the labels within <br />the printout from the SEDCAD model. <br />As discussed below in response to Review Comment 18 k, the names of those ditches have <br />been revised in the SEDCAD model to remove the word "contour". The reason they were <br />previously called out as "contour ditches" is provided below in the response to Review <br />Comment 18k, but that confusing nomenclature has been corrected. <br />j. The slopes in SEDCAD model seem to be greater than those shown on the topographic map <br />in Figure Exh. 7-14PP-8. Please check the slopes in the SEDCAD model and correct as <br />necessary. If this was done to be conservative in the SEDCAD modeling please provide an <br />explanatory note. <br />Response: It is not clear whether the review comment deals with channel slopes presented for <br />each individual channel throughout the SEDCAD output or the overland flow slopes in the <br />sedimentology portion of the model which is presented on pages Exh. 7 -PP -299 through Exh. <br />7 -pp -347. There are 19 channels with slopes that are input into the model, and 33 sub - <br />watersheds, each of which has a slope calculated by SEDCAD based on user input (slope <br />distance and elevation drop). However, we obtain the raw data for the channel slopes and the <br />overland slopes in the same way. This consists of laying a horizontal line one the slope in the <br />Autocad drawing, measuring its length, and determining the elevation drop by counting <br />contours. For a ditch, which may have several reaches of slightly different slope, we usually <br />select the steepest as that produces a more conservative rip -rap sizing or a most critical flow <br />velocity for the case of grass lined channels. For the overland flow in the sedimentology <br />Page 6 <br />