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<br />90% of the reach is located on federallands managed by the USFS, 5% is state lands managed <br />by the Colorado Division of Wildlife and 5% is located on private lands. <br /> <br />Biological Data <br /> <br />Colorado Division of Wildlife (CDOW) conducted field investigations of Middle, East, and <br />mainstem Escalante Creek (CDOW 1977). Due to low flow conditions during the time of <br />sampling, no fish were found in Middle Fork and East Fork Escalante Creek. However speckled <br />dace have been observed in small pools in Middle Fork Escalante Creek during 2003 (James <br />pers. comm.). Bluehead and flannelmouth suckers, speckled dace, rainbow trout, and fathead <br />minnows were captured in the mainstem of Escalante Creek (CDOW 1977). Biomass was <br />highest for bluehead suckers in the lower reach and rainbow trout in the upper reach. <br />Additionally, CDOW has stocked all three streams frequently since 1973 (Appendix B). <br /> <br />Habitat conditions for both East Fork and Middle Fork Escalante Creeks are good. A healthy <br />willow community exists along both streams, with good stream cover, primarily undercut banks, <br />boulders, and overhanging vegetation. Fine sediment is high in the lower reaches of both <br />streams, but lessens as the stream moves higher upstream into USFS lands. Temperatures are <br />also warmer in the lower portions of both streams, but cool in the higher elevations. During the <br />summer, water tables are higher in the upper portions of the watershed, with more surface water <br />in the upstream portions of the stream, and more intermittent or low flow conditions toward the <br />lower terminus of both East Fork and Middle Fork Escalante Creeks. <br /> <br />Field Survey Data <br /> <br />USFS staff used the R2CROSS methodology to quantify the amount of water required to <br />preserve the natural environment to a reasonable degree. The R2CROSS method requires that <br />stream discharge and channel profile data be collected in a riffle stream habitat type. Riffles are <br />most easily visualized, as the stream habitat types that would dry up first should streamflow <br />cease. This type of hydraulic data collection consists of setting up a transect, surveying the <br />stream channel geometry, and measuring the stream discharge. Appendix B contains copies of <br />field data collected for this proposed segment. <br /> <br />Biological Flow Recommendation <br /> <br />The CWCB staff relied upon the biological expertise of the cooperating agencies to interpret <br />output from the R2CROSS data collected to develop the initial, biologic instream flow <br />recommendation. This initial recommendation is designed to address the unique biologic <br />requirements of each stream without regard to water availability. Three instream flow hydraulic <br />parameters, average depth, percent wetted perimeter, and average velocity are used to develop <br />biologic instream flow recommendations. The CDOW has determined that maintaining these <br />three hydraulic parameters at adequate levels across riffle habitat types, aquatic habitat in pools <br />and runs will also be maintained for most life stages of fish and aquatic invertebrates (Nehring <br />1979; Espegren 1996). <br /> <br />For this segment of stream, two data sets were collected with the results shown in Table I below. <br />Table I shows who collected the data (Party), the date the data was collected (Date), the <br />measured discharge at the time of the survey (Q), the accuracy range of the predicted flows <br />based on Manning's Equation (240% and 40% of Q), the summer flow recommendation based <br /> <br />- 3 - <br />