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<br />coefficients, bridge information, reach lengths, and other input parameters shall be reviewed <br />by the ENGINEER and revised as necessary. <br /> <br />6) Determination shall be made for a 100-year floodway on Fourmile Creek from its confluence <br />with the Arkansas River upstream to the south side of U.S. Highway 50. The floodway shall <br />be based on encroachment resulting in a maximum increase in the water surface elevation of <br />1.0 feet. Encroachment and conveyance assumptions shall follow FEMA guidelines and <br />specifications. A previous floodway analysis was not performed by the NRCS. <br /> <br />7) The following information shall be depicted for the STUDY REACH by the ENGINEER <br />using the NEW MAPPING as a map base: <br /> <br />a) Limits of the 100-year floodplain and floodway based on the design 100-year flows for <br />existing basin and channel conditions. <br />b) Profiles of the bottom of the channel or thalweg, and the 10-, 25-, 50-., 100-, and 500- <br />year water surfaces. <br />c) Cross-section locations. <br />d) Stream centerline (reference line) and stationing. <br />e) A sufficient number of 100-year flood contours to enable reconstruction of the 100-year <br />water surface profile to an accuracy of +/- 0.5 feet. <br /> <br />8) The ENGINEER shall produce plan view floodplain drawings plotted on 11 "x17" sheets at a <br />plotted scale of 1 inch = 400 feet. Profile sheets shall also be produced. and plotted on <br />1l"x17" sheets at a plotted scale of 1 inch = 200 feet (horiz.) and 1 inch == 10 feet (vert.). <br />Computed water surface profiles and profile plots shall match within 0.5 feet of the NRCS <br />study at cross-section 310. <br /> <br />9) The ENGINEER shall prepare a bound one-volume written report summarizing the study <br />findings and analyses. The report shall be signed and sealed by the registered professional <br />engineer responsible for. its contents. The report shall include the new information produced <br />from this STUDY and shall incorporate pertinent information from the 1996 NRCS study. <br />The report shall be compiled in such a way that it will supersede, but will make reference to <br />and give credit to, the affected and revised portions of the NRCS study. This report is not <br />intended to supersede the entire NRCS report, but shall supplement and replace the revised <br />portions of it. The ENGINEER shall prepare a report that contains the following: <br /> <br />a) A one page executive summary and table of contents with a list of figures, maps" etc. <br />b) A brief statement to clarify the scope and purpose of the study and to present the <br />obligations of the ENGINEER under this agreement. <br />c) A summary of pertinent data or information obtained from the CITY, the CWCB, the <br />NRCS, and others. <br />d) A summary of the study area and watershed. Identify major basin features in the text and <br />include a good quality basin map with identifiable features and landmarks. <br />e) Related flood studies. <br />t) Flood history. <br /> <br />3 <br />