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<br />, <br />III, FLOOD HAZARD FINDINGS AND MITIGA TION RECOMMENDATIONS <br /> <br />Summary of Findings <br />CWCB staff conducted additional field investigations and ground surveys on October I, 1997 in <br />the Lower Elk River vicinity. The CWCB's flood hazard findings are as follows: <br /> <br />1. The peak overflow (weir flow) across County Road 44 (just north of Highway 40) was <br />estimated to be 250 cfs. In addition, right overbank flows were conveyed to the West Fork <br />Elk River and Elk River by other conveyance paths (culverts through Highway 40 and open- <br />channel flow paths). <br /> <br />2. The existing culvert that drains water from the northeast corner of the intersection (County <br />Road 44 and Highway 40) to the southwest corner of the intersection is undersized. The <br />capacity of that culvert is much less than 250 cfs. This undersized culvert causes a serious <br />inundation problem upstream of County Road 44. <br /> <br />3. The existing culvert that drains water from east to west beneath the driveway to Saddle <br />Mountain Ranch is undersized. During high flows, water backs up behind the SMR driveway <br />and is slowly released to the West Fork of the Elk River. This causes a condition of ponding <br />water on the adjacent lands on the north side of Highway 40. <br /> <br />4. The existing culvert beneath Highway 40 (just west of County Road 44) has an adverse slope. <br />The culvert drains from south to north, rather than north to south. <br /> <br />5. The existing drainage ditch located along the north side of the railroad right -of-way is not <br />graded properly to drain to the West Fork of the Elk River. An existing driveway on the <br />south side of Highway 40 (just west of County Road 44) completely blocks the drainage <br />ditch. Water on the east side of the driveway essentially gets trapped behind the driveway <br />embankment. <br /> <br />6. The Highway 40 borrow ditches (south side and north side) are not properly designed to act <br />as floodwater conveyance channels to get the flood flows to the West Fork Elk River. The <br />County Road 44 ditches are also not designed to function as flood conveyance channels <br />during periods of high water. <br /> <br />7. The lower reaches of the Elk River consisting of the East Fork and West Fork have many <br />flood and streambank erosion problems. If these problems are not addressed, they could pose <br />serious risks in the future. <br /> <br />2 <br />