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<br />. <br /> <br />. <br /> <br />. <br /> <br />Flows in excess of the design event on the mainstem would thus necessitate providing the project <br />features at the Riverside Cemetery. Alternative No.5 would decrease the severity of the 100-year <br />flood event in the area west ofHWY 6 between the Pawnee Creek bridge and the Cemetery, but would <br />not eliminate all overflows. In addition, this alternative would provide flood benefits to the community <br />of Town of Atwood. <br /> <br />Alternative No.6: This alternative provides a drainage floodway upstream of the Town of Town of <br />Atwood that diverts Pawnee Creek to the south, along CR. 29 directly to the South Platte River. The <br />floodway would be sized for the I DO-year storm peak flow and would handle a discharge equal to the <br />July 1997 flood event at that location. This alternative would require crossings for the Pawnee <br />Irrigation Ditch, and both HWY 6 and the UPRR. <br /> <br />Summarv Recommendations <br /> <br />All of the alternative projects were conceptually designed in adequate detail to provide relative cost <br />and benefit comparisons. A matrix was prepared of project pros and cons. This information was <br />presented to the City, County, and interested citizens. A total of seven public meetings were held to <br />discuss the various alternatives. Several factors were used to evaluate and prioritize the projects and <br />their components. Alternative No. I "No Action" was not acceptable from the Citizen's standpoint as <br />there was generally great concern regarding the potential for future damaging floods. Alternative No.2 <br />was believed to have a technical flaw, in that construction of required freeboard on the levee might <br />increase the level of flooding in the Town of Town of Atwood if a flood of greater magnitude than the <br />I DO-year design flood occurred. Alternative No. 3 "Construction of Darns" was eliminated due to the <br />lack of cost effectiveness and the unavailability of funding for projects of this magnitude. Alternative <br />No.4 was acceptable to the City of Sterling, but does not provide any flood relief to Logan County and <br />Town of Atwood. Alternative No.5 was acceptable to both Logan County and the City of Sterling and <br />had the greatest overall support. Alternative No.6 was generally acceptable, (except for the land <br />owners who would be directly impacted by the improvements), but was perceived to have more <br />unknowns that could potentially increase costs. <br /> <br />The weighted scores for each of the proposed projects and their components are presented in the <br />following Table with the suggested alternative ranking. <br /> <br />Table 3. Weighted Implementation Scores <br /> <br /> <br /> <br />1 No Action <br />2 Pawnee Creek 100- Year Levee <br />3 Upstream Flood Control Dams <br />4 Riverside Cemetery Channel <br />5 Modified Pawnee Creek and <br />Cemetery Levees <br />6 Town of Atwood Channel By-Pass <br /> <br />WEIGHTED <br />..SCORE <br />N.A. <br />415 <br />250 <br />370 <br />555 <br /> <br />6 <br />2 <br />5 <br />4 <br />1 <br /> <br />410 <br /> <br />3 <br /> <br />1-10 <br />