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" " He ~tated that a couple of agricultural fields along the Roaring fork were w~~hcd Out and al.o that the entire valley wllere the KOA Campground i5 now located had been completely flooded several tlmeslnhis.....mory. Mr. Lucksinger ,,150 saId the Fryingpan River does not flood very often but during the 1957 flood, it wilshed out a road 60 feet from the river. No urban areas are affected by floods. The principal items damaged by the 1957 flood were the agricultural lands and mads and bridges adjacent to, of over, the river. A few farm buildings were flooded. The total known damages in all categories in this reach amounted tosllghtlymorethanS45,OOO. In compliance with the requests .. .an inspectIon of the problem areas on Roaring Fork River was made by Corps representatives On 12 and 13 December 1957. The Inspection covered a 14-mile reach begin- nlng 2 miles above Basalt, Colorado, and ending at Carbondale, Colorado, 12mllesl>clowBasalt.. . Acormlontypeofd<lmage froothe 1957 flood was bank erosion. The slope of the stream ranges from 65 feet per mile above Basalt to 40 feet per mile below Basalt. VelocitIes probably in exCesS of 10 feet per second occurred during the 1957 flOOd. The banks are composed largely of sand, gravel, and cobbles overlain by a compar- atlvelythinrnantleofsoll,andarequlteerOSlble. Spoil-type dikes, constructed by local Interests with material bulldozed in the process of channel clearIng, proved to be very eroSible. The following excerpts from the Corps of Engineers letter report also deal wi th the results of the July 1957 flood. Roaring Fork River rIses at the Continental Divide on the western slope of the Rocky Mountains near Independence Pass, in central Colorado. It flows northwesterly for a distance of appro><lmately 60 miles to its confluence with the Colorado River near Glenwood Springs. It is fed by glaciers on peaks ranglng in altitude to 14.DOOfeetandabove. One of Its principal tributaries is the Fryingpan River. Their junction Is at Basalt, Colorado. The Frying- p~n River contributes nearly one-half of the combined flow below the junction during floods. A substantial percentage of the total damages was due to overtopping of the low banks and the inundation of pasture and croplands. The banks inmost Instances range from only 2 to5feet inhelght. In two locations, where old Channel areas have been reclaimed, consid- erable volumes of overflow and widespread flooding resulted from bank overtopping at the up~er ends of the areaS. More than one-half of the known damages In the 1957 flood were caused to roads and bridges In the area, with nearly $2~,OOO of damages being caused to three bridges and their abutments. Two of these were public bridges and have since been restored. Ath;rdbridge, which waS private was completely destroyed and has not been replaced. Flood. 00 the Roar;ng Fork result from snowmelt and occur principally during the month of June. The fioodof J\lly1, 1957 had an Instan- t~~",ous p""k ~;sc~arge of 18,700 cfs at the Glen';IOOC $prlng5 g<lgc. This flood was thernaximunlof49yearsofrecord,and its magnitude has an estimated frequency of OCCurcnCe of once In approxImately 60 years. T~ 18,700 cfs instantaneous peak discharge referred to In the Corps of En- qin~ers lpttpr report has been revised to 19,000 cfs by the U. S. Ccologlcal ~urvey. Ih,s ,s the maximum instantaneous peak discharge recorded at the Glenwood Springs gage On the Roaring Fork River through 1976. The river in the problem area is characterized by low banks, braided channels, and a considerabl" alTlOunt ofgravel,cobb\es, and snag s deposited on gravel bars. The river carrIes a largebedle<odof gravel and cobble~, SOme of the l~tter being more than 6 inches in d I~meter. The capacT ty of the channel has been reduced by this sedi""'nt. Insoote ;nstances, where chanr.cl ch.:lnges took place durlr,g thef\ood. tneoriginalchanne\sW<!re.ofil\edwlths"dlmentthat nearly all of the present flows are dIscharging through the "new " channels. Generally, howe..,r, the "new" channels are old watercourses abandoned by the river in prcvlous years. The littered condition of the c~anne Is, and th.. increased danger of bank erosion, inundat 10n. and add II i "n~ I channc I chang..s re~u 1 t I ng from th i ~ co",! i t ion. con- stitute the pre'ent flood problem.