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3 . I' ,. Wellington. From our analysis and computations, we contend that the Boxelder Channel, with or without the flume will handle a 100 year frequency flow (see exhil1it G) again considering that the Iloxelder Creek contrihution to thC' 100 year frequency peak flow is approximately 10,000 cfs. . The merging of any Boxelder and Coal Creek flood waters IS not possible north of the area of the flume (cross section 27) due to a hilly rise and a railroad berm which averages 6 to 8 feet in height. These obstructions would keep the Boxelder flood waters on the west side of the tracks until it reached the flume (see exhibit H) and our figures show that adjacent to Wellington (cross sections 27, 26,25,) the Boxelder channel is large enough to handle a 100 year frequency peak flow. Thus, any 100 year Boxelder Creek flood water would be obstructed on the east by a hilly rise, then a railroad berm, until it reached the flume where it would be contained in its natural channel as it flowed through the Wellington . area. . As was mentioned, the Coal Creek contribution to the 100 year frequency peak flow is approximately 3300 cfs. It is our contention that any flooding which might take place along Coal Creek will be diverted into two large irrigation ditches which cross it at right angles. The North Poudre Ditch, which empties into Clark Reservoir, intercepts Coal Creek at two locations about 3 miles north of Wellington. Our analysis and computations show \hat this ditch will handle approximately 2800 cfs (see exhibit J and JI). Any flood water which might over run the North Poudre Ditch would have to travel as overland flow (Coal Creek ceases to exist 2 miles north of Wellington) 2 1/2 miles to reach the Wellington area where the Windsor Ditch would then intercept this flow. Our analysis and computations show that this ditch will handle approximately 1400 cfs (see exhibit K and KI). The combined capacity of both ditches - 4200 cfs - should handle any 100 year frequency flooding along Coal Creek. . . . . It should be noted that the North Poudre Ditch carries approximately 400 cfs during the irrigation season and the Windsor Ditch is used only as a conduit for transporting reservoir water. No more than 450 cfs of water is transported at any one time in the Windsor Ditch. . The Water Resources Division of the United States Geological Survey was requested to make an estimation of the 100 year flood peak flow in the Boxelder Basin at Wellington. Included in this report (exhibit L) is a memorandum from the United States Geological Survey gIvIng an estimate of this peak flow. Of the three estimates made, using different methods, the greatest was 8700 cubic feet per second. The memorandum further states that no flood threat is presented by Coal Creek to the town of Wellington. .