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I provide extra flood protection during the high Spl'ing runoff in 1983. The levee was constructed of loosely compacted soils, and was actually placed over the existing road adjacent to the river. The road has since been cleared and a loosely compacted mound of soil remains on top of the existing gab ion wa 11. 2) The second major levee system is located downstream of the Grand Avenue _.._~.~. ". '._'"~- -", Bridge along the south b,ank,..of the Colorado River and extends approximately 3900 feet downstream. This area is protected by an existing permanent levee --wh;'ch'was increased in height during the higl:! flood waters of 1983. The permanent levee consists of compacted granular soilswithlittle bank pr2t~ct~(),n on the river side..~Jarge trees a16ng the 'wafer:s.,edgeheJpto stabiiTze the bank and protect it from erosive velocities. There was evidence of extensive erosion and bank failure during the high spring runoff at various locations. In the area adjacent to the fepsi Cola Plant and upstream to the Grand ~-~, --.~~ ,,-'.....-- Avenue bridge, the t"mporary levee was constructed with loosely compacted soi 1 and placed on t)P of the permanent levee. In the area downstream of the Pepsi Cola Plant, the temporary levE~e looked to be compacted by rTla~ntenance~quipment, such as trucks and front end loaders. Side slopes of the temporary levee are steep and loosely compacted with no protE~ction on the river side. Our ing the period of high flows, bon ing was experienced --'-'- .-,----.._.._-~.-,,,.--_. . _~,:der ..~_E ort i on _Q:L.1..be,.!~~s_tJ nL!,e,yee.. jU~~,~(~w.n? tre,alll_..(),f.Jb.e::p'eR?iXl,anLin,., the "Connected ..1.ilkes" region.. This wou'ld indicate that there may be . -"~'----~- -.....--.......---_..,...-,-~^._--,-"'....~ foundation problems due to sand lenses, unsuitable soils, or animals burrowing under the tank. 3) The last major levee system investigated was the levee which diverted the Colorado River north along the Mathews I~cJ,y~txi?lPar,~ and formed the lake known as "Reese Lak~~'. The "TaFe"..wa's.... ~onstructed CIS part of a mining operation north and west of Dike Road. During normal flows, the levee directed the river tc the north into a constricted channel section. During the 1983 flood, flows forced into the constriction resulted in high, erosive velocities along the bank bordering the Mathews Industrial Park. The bank failed at that location and two storClge b'JildinCjs were lost. The levee bordering the lake eventually failed creating an additional channel which helped reduce the erosive velocities on the bank, and also lowered the water surface elevation upstream. The existing levees .'ithin the study reach are generally in poor condition, They are constructec of san_dy, non-cohesive sO,il5 with poor compaction ~~~l.it_~,~s..:__The levees exhT6it steep, unprotected side slopes having little or no vegetation, e>:cept for some large t'rees along the channel banks, 7