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"lightersideofthenews"inplcturingchildrenatplayinthemud aLd water left by a receding flood. Unfortun~tely, however, the contamination threat to domestic water supplies cannot be illustrated with similar ease. result in depths of flow of up to 7 feet over the railroad yard. This condition prevails only as far west as Anderson Arroyo. On King Arroyo, between 4th Street and 8th Street, the Standard Project Flood will inundate a portion of the residential area, including the high school athletic field on the ~est side of the arroyo. B<ot....en 4th Street and 6th street, the 50~year and 100-year floods will flood small areas, reaChing about 200 feet from the arroyo. All four floods on Anderson Arroyo will result in some flooding in the vicinity of the u.s. Highway 50 orossing and in the vicinity of the 10th Street crossing. For the re~ainder of the study reach, the 25-year flood is largely contained. All other floods will result in floodinq throughout the st~y ar~a. The 100-year flood divides in the vicinity of 3rd Street with flow e~caping to the ,...st, crossing U.S. Highway 50, and rllenterinq th" mainchi!l.nnelviathe""",Usid"channelonthesouthsideofth" railroad crossing. Table 3 presents Floodwater Surface Elevations at cross sections along the Ark.ansas River, King Arroyo and Mderson Arroyo. Flooded Areas and Flood Damaqe. Thestudyareassubje<::t to tlooding by the 100-year flood and Standard Project Flood are shown on Plates 1 through 15. Plate a is an index map showing the relative location of the flooded area plates within the study area. Actual linlits of overflow areas IMY vary from those sh""", on the flooded area plates because of variation between plate contours and locations of contours on the ground. Depths of flow for any location along any stream can be estimated from the flood p~ofiles shown on Plates 17 through 26. Floodwater elevations determined in any particular are" are not always indicative of the depths actually attained, often floodwater becomes isolated and trapped in overbank areas resultinq in depths greater than thos.e shown. The 25-, 50-, 100-, and Standard Project FlOOds on the Arkansas River will result in extensive flooding along the north ~id.. of the Arkansas River. Depths of flow in North La Junta and La Junta Gardens range fr~ 1 to 2 feet for the 2S-year flood, up to 8 to 9 feet for the Standard Proj..ct Flood. The levee along the north side of the river was found to be ineffective even for the 25fiyear flood. Water will flow over the top of the levee near the south end of Jachim Avenue and will also reach the north side by flowing under the Dike Road bridge at the Fort Lyon Canal l"teral. On the south side of th" Arkan,.a" River, all four floods will n-aGh the re~identia1 and business areas between King Arroyo and St~en Avonue. West of Raton Avenue, only the Standard Proj'K't 1'1(><><1 will r<,,~ch soutb <>f bt Stre..t. All four floods ,,(11 lnun<l~l,' U,,' rdj)- roadyardsaltho\1<;h the2S-y"ar flooo"UI s\1bmerg.' only the portio" betweon St~en and Harriet AvenuQs. Th~ Stand~rd Project Flood will Obstructions. Maintaining the channel and overbank capa- city to convey floodwater through the cOltll'OUnity without causing ",er- ious flood d~~ge should be of m4jor concern. Restricting the floodway by bridges and their approach embankments, roadbeds or otherwise changing channel and ~.erbank c,,~citie~ will impede flood flows and callse greater backwater depths with consequent in. crca~c in flooded are~s. The growth of vege~tio~, obstructive ~ew dll"eiopment~ or 1a~d filUng in a Btream's floodway can be a mitior (~clur in multiplying the ~dvers.. effects described. P<.>r "tutl.,. prupo~es herein, it has been ass~d that limited Clogging of bridg~s and culverts will occur and that all bridges and culverts will stand intact during floods of IOO-year and Standard Project frequency. Sig- nificant chil.nge~ in Uds premi~e could alter the flood "rests and ClouJ limit:> ~i...w" in .<el"ted pl"tes and tables. " "