Laserfiche WebLink
<br />292(1 <br /> <br />xii <br /> <br />" <br /> <br />The safe channel capacity of the ~outh Platte River has been estimated to be <br />about 10,000 cfs. Admittedly, there are some minor damages and nuisances created <br />'vith flows less than that, but there is essentially no real flood danage until the <br />stage exceeds 10,000 cfs. For flood control operation, water would be stored only <br />at such tile,es as this safe channel capacity is exceeded, and only those flows in <br />excess of 10,000 cfs. would be stored. After the flood crest had passed and inflow <br />was again below the safe channel capacity, releases \/ould be maintained at the <br />10,000 cfs rate to evacuate the water in storage to make the space available for <br />controlling a subsequent flood. In the event a flood occurs of a magnitude larger <br />than can be accommodated in the reservoir, spillway gates are operated to release <br />an amount equal to the inflow so that flood damages are not increased by operation <br />of the reservoir. ~he flood control capacity provided in a reservoir is normally <br />based on controlling floods of record. <br /> <br />For irrigation, use, of course, a full reservoir is most desirable and releases <br />are made only when water can be beneficially used. Thus, it can be seen that the <br />principles for operation of a reservoir for flood control or irrigation purposes <br />are diametrically opposed. Unless a flood control reservoir is operated in the <br />manner outlined above, no flood benefits except those incidental to the operation <br />for other purposes could be claimed. <br /> <br />Hardin ~ite.--This site was eliminated from further consideration because of <br />insufficient capacity to achieve full flood control benefits on either the bouth <br />Platte rtiver or Bijou Creek. Use of this site for conservation purposes would <br />require a dead storage capacity of 191,000 acre-feet to supply the ~mpire Canal. If <br />the capacity of the Hardin site were used to store water for irrigation, with water <br />held over until such time as it could be used for that purpose, only minor incide~t- <br />al flood control would result and nearly all costs of construction would have to be <br />) considered as reimbursable. under such an arrangement, the Hardin site could pro- <br />duce far fewer benefits than Narrows and is clearl~' lCS3 feasible than Narrows. <br /> <br />GOOdrich Site.-Foundation conditions are unfaV01'E':;:;'e at this site, and the <br />volume of embankment necessary to develop the req~ired storage would be excessive. <br />Outlets for both the Jackson Lake Inlet and the Weldona ';anal wollld be req'.lired <br />in the north abutment of the dam. Sediment would enter the reservoir from Kiowa <br />Creek near tre damsite and endanger the embankment. The factor of high cost and <br />the potential danger to the embankment eliminate this site vhen it is compared with <br />the dovmstream sites 'of V[eldona, Narrows, and Fort lbrgan. <br /> <br />Old ~ort h0rgan ~ite.--The reservoir site is physically limited, and dead stor- <br />age would be large since the Fort Morgan canal "ould be located at a relatively high <br />elevation with respect to the ciam. This site was eliminated on the basis of cost, <br />n limited capacity, and potentially unfavorable groundwater conditions downstream from <br />the dam. <br /> <br />Weldona Site.-The Weldona site ~IaS eliminated from further consideration and <br />study on the basis of costs. <br /> <br />Final ~lection of ~ite <br /> <br />The 9~tection o~ a,~es~rvoir si~e on file b9Uyh ~~~t~ Hfv~r was fi~ally narrowed <br /> <br />'" <br />