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The CDOW has evaluated the 100 cfs year -round instream flow recommendation, based on their <br /> data collection efforts (see Table 1 and Appendix A). The modeling results from this survey <br /> effort are within the confidence interval produced by the R2CROSS model. <br /> Biological and Field Survey Data <br /> As reported in the letter from CDOW to the CWCB (attached), "This reach of the Arkansas <br /> River is classified as a large river (over 100 feet wide) and fishery surveys indicate the stream <br /> environment of this reach of the Arkansas River supports Black bullhead (Ictalurus melas), <br /> Central Stoneroller (Campostoma anomalum), Channel catfish (Ictalurus punctatus), Common <br /> Carp (Cyprinus carpio), Fathead minnow (Pimephales promelas), Flathead chub (Hybopsis <br /> gracilis), Gizzard shad (Dorosoma cepedianum), Green sunfish (Lepomis cyanellus), <br /> Largemouth Bass (Micropterus salmoides), Longnose dace (Rhinichthys cataractae), Longnose <br /> sucker (Catostomus catostomus), Orangespotted sunfish (Lepomis humilis), Plains killifish <br /> (Fundulus zebrinus), Red Shiner (Cyprinella lutrensis), Sand shiner (Notropis stramineus), <br /> Saugeye (Stizostedion vitreum x S. canadense), Walleye (Stizostedion vitreum), White crappie <br /> (Pomoxis annularis), White sucker (Catostomus commersoni), Wiper (Morone saxatilis x M. <br /> chrysops), Rainbow trout (Salmo gairdneri) and Brown trout (Sahno trutta). <br /> Suckermouth minnow (Phenacobius mirabilis) historically inhabited this reach of the Arkansas <br /> River but have been absent from recent fishery surveys. Flathead chub (Platygobio gracilus) and <br /> Suckermouth minnow ( Phenacobius mirabilis) have been identified by the DOW and several <br /> other state and federal agencies as "species of greatest conservation need ". DOW is involved in <br /> developing Conservation and Management Plans for these species. The intention of these plans <br /> is to increase populations and distributions of identified species, thereby assisting in the long- <br /> term persistence of each species. The success of such plans could potentially curtail the need for <br /> federal listing of these species under the Endangered Species Act (ESA). These species are not <br /> currently federally listed" (See CDOW Fish Survey in Appendix B). <br /> Field Survey Data <br /> CDOW staff used the R2CROSS methodology to evaluate the recommendation and determine if <br /> it would preserve the natural environment to a reasonable degree. The R2CROSS method <br /> requires that stream discharge and channel profile data be collected in a riffle stream habitat type. <br /> Riffles are most easily visualized, as the stream habitat types that would dry up first should <br /> streamflow cease. This type of hydraulic data collection consists of setting up a transect, <br /> surveying the stream channel geometry, and measuring the stream discharge. Appendix B <br /> contains copies of field data collected for this proposed segment. <br /> Biological Flow Recommendation <br /> The CWCB staff relied upon the biological expertise of the CDOW to interpret output from the <br /> R2CROSS data collected to evaluate the instrearn flow recommendation. Three instream flow <br /> hydraulic parameters, average depth, percent wetted perimeter, and average velocity were used <br /> to evaluate the instream flow recommendation. The CDOW has determined that maintaining <br /> these three hydraulic parameters at adequate levels across riffle habitat types, aquatic habitat in <br /> pools and runs will also be maintained for most life stages of fish and aquatic invertebrates <br /> (Nehring 1979; Espegren 1996). <br /> 7 <br />