Laserfiche WebLink
<br />. <br /> <br />. <br /> <br />. <br /> <br />required. In these cases, CWCB staff relies upon the biological expertise of the cooperating <br />agencies to develop a biologic instream flow recommendation. <br /> <br />The CDOW has indicated that this is a high priority stream segment to them. However, because <br />the winter recommendation falls outside the accuracy range of the R2CROSS model, staff <br />believes that more data needs to be collected to accurately predict the winter flow <br />recommendation. To determine the winter flow recommendation, staff considered the proposed <br />winter recommendation for Spring Creek of 0.8 cfs. After consulting with the Colorado Division <br />of Wildlife, staff believes 0.8 cfs will be sufficient to protect the natural environment to a <br />reasonable degree if water is available (See Table I). <br /> <br />Hydrologic Data <br /> <br />After receiving the cooperating agency's biologic recommendation, the CWCB staff conducted <br />an evaluation of the stream hydrology to determine if water was physically available for an <br />instream flow appropriation. There are no currently operated or historically operated <br />streamflow gages for this reach. The closest gage CWCB staff found was the gage located on the <br />Ruby Anthracite Creek near Floresta 15 miles southeast of the Spring Creek drainage. The <br />hydro graph was derived from data collected by the USGS stream gage for Ruby Anthracite <br />Creek near Floresta, CO (ID #09132000), which has a drainage area of 20.7 square miles. The <br />drainage area of Spring Creek is approximately 4.8 square miles. Staff used a basin <br />apportionment method to estimate stream flows for Spring Creek (See Gage Summary in <br />Appendix C). The period of record for this gage was October 1938 to September 1943 and <br />October 1954 to September 1958, the period ofrecord used by staff in their analysis was October <br />1938 to September 1943 and October 1954 to September 1958, or nine years of record, the gage <br />was not operating the whole period of record. Table 2 below displays the estimated flow of <br />Spring Creek, in terms of a percentage of exceedence. <br /> <br /> Januarv Februarv March Ami! Mav June Julv Auaust September October November December <br />1% 0.81 1.14 1.77 41.04 99.78 135.19 129.97 20.76 6.40 8.47 3.94 1.39 <br />5% 0.81 0.70 0.96 20.41 77.96 105.39 68.50 10.68 4.06 4.88 2.32 1.39 <br />10% 0.81 0.70 0.81 12.99 67.50 88.35 34.11 5.36 2.78 3.94 2.32 1.39 <br />20% 0.65 0.63 0.81 9.28 56.12 73.28 17.39 3.48 1.90 2.78 0.81 0.70 <br />50% 0.53 0.46 0.63 4.41 41.74 46.14 6.03 1.62 0.90 0.81 0.67 0.49 <br />80% 0.30 0.28 0.42 1.46 21.06 27.36 3.01 0.92 0.56 0.44 0.44 0.41 <br />90% 0.28 0.14 0.35 1.02 13.17 18.78 2.11 0.81 0.46 0.39 0.42 0.37 <br />95% 0.19 0.14 0.19 0.78 9.28 15.19 1.81 0.72 0.39 0.35 0.37 0.30 <br />99% 0.16 0.14 0.14 0.42 6.03 9.23 1.49 0.51 0.32 0.30 0.32 0.21 <br /> <br />Spring Creek Estimated Stream Flow <br /> <br />J!! <br />u <br /> <br />50 <br />40 <br />30 <br />20 <br />10 <br />o <br /> <br /> <br />~ <br />~ <br /> <br />,('-~ ~-? -1~ ~)- VV-V V~ <br /> <br />-1vQ O'~,() Dc=>, -VO~ O~O <br /> <br />Month <br />