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<br />For comparison, we analyzed a hypothetical flow of 20 CFS <br />(5.35 times the required flow). Attachment 5 and 6 provide an <br />analysis of the theoretical ditch requirement for the elevated <br />flow level and indicates the flow depth of .91 feet and 7.30 <br />feet of width is required. <br />Even with the flow of water in excess of 5 times the <br />necessary flow volume the ditch would continue to contain the <br />flow. <br />The comparative analysis is actually quite conservative <br />because the ditch width averages nearly 12 feet in width <br />rather that than 9.1 feet shown on the Typical Cross-Section. <br />The net result is that in reality the ditch was built far iit <br />e:;cess of theoretical recuirements. In no cvay did Colowyc <br />"fail to construct appropriate sediment control measures" as <br />asserted by the Division. <br />2) After closer review of the specific section of ditch it <br />is apparent that the cause of the problem can be attributed to <br />the snow drift that typically collects on such steep north <br />facing slopes. Unfortunately, when snow begins to melt on the <br />south facing slopes the runoff is often unable to get through <br />the "blocked" ditch segments on the north facing slopes. When <br />this occurs the ditch failed to contain the runoff which <br />subsequently flowed out of the ditch. These kinds of events <br />are unpredictable and beyond the capacity of Colowyo to <br />control. <br />3) Early in April Juan Garcia of Colowyo, first noticed the <br />problem areas. Due to the wet conditions the ditch was <br />virtually impassible by dozer so Juan initially repaired the <br />ditch with a shovel. As April was a record month in terms of <br />precipitation (over 4"), we were not able to get a dozer into <br />the ditch in a timely manner. In late April, we were able to <br />get a dozer into the ditch but due to the deep mud we were <br />only marginally successful in making initial repairs. Final <br />repairs were to be completed when the conditions allowed. <br />The DMG inspection encountered the ditch in this interim <br />period during which maintenance was being completed. The <br />ditch was indeed functioning but not at its design capacity. <br />4) The ditch repair portion of the NOV was completed on May <br />19, 1993. <br />5) The NOV states incorrectly that "Untreated runoff down <br />unnamed stream immediately to southwest of Prospect Pond". <br />Rather, the runoff flowed into a primarily dry ephemeral <br />drainage and not into a stream. <br />