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<br />\ <br />J <br />1 <br />1 <br />1 <br />j <br />i <br />I <br />1 <br /> <br />11 <br />I <br />I <br /> <br />:J <br /> <br />I <br /> <br />I <br /> <br />I <br />! <br />f <br /> <br />. <br /> <br />J <br /> <br />. ~~-"';"""";-r:;Ji'l:'~::~--:',;..;':n.~;":(;1:~ft'if.io,Jfw&&":.~";",,,,: <br /> <br />-;.ao.__ <br /> <br />~.~ <br /> <br />are included with this report. The cross-sections have <br />been plotted and flow distributions for each cross-section <br />are provided as well. <br />The obvious back-water effect caused by flow over <br />Prospect Street ponds storm water over much of Prospect <br />Meadows property. The floodplain is contained within the <br />westerly top of the bank of Boxelder Creek (see Cross- <br />Section 80), however, as it enters the north-easterly <br />limit of the property; so no problem exists with respect <br />to floodwaters entering the property along an extended <br />portion of Prospect Meadows' northerly boundary. <br />To determine the effect on the floodplain characteris- <br />tics by protecting the property from inundation by water <br />ponding behind Prospect Street, encroachments were included <br />on Cross-sections 60 and 70 at a location where earthen <br />berms can be placed to contain the flood waters easterly of <br />those encroachment locations. <br />The H.E.C. 2 computer printout showing the effect of <br />encroachment into the floodplain for protection of Prospect <br />Meadows is also included with this report. As indicated on <br />the printout, the effect on the floodplain characteristics <br />is minimal. A maximum increase in the water surface eleva- <br />tion CWSEL of 0.15 feet occurs at Cross-Section 80; while the <br />increase at Cross-Section 70 is 0.08 feet and a.decrease of <br />0.11 feet (due to an improved hydraulic section) occurs at <br />Cross-Section 60. <br />The average velocities in Cross-Section 60 and 70 have, <br />of course, increased, but not significantly enough to be <br />hazardous. In fact, the maximum average velocity of flow <br />adjacent to the proposed earthen berm will be only 2.2 feet <br />per second (fps). <br />An earthen berm is proposed that will be aesthetically <br />pleasing and a part of an overall landscaping and planting <br />scheme. The earthen berm is proposed for protection from <br />