Laserfiche WebLink
<br />below 600 and 2) provide a temperature gradient of less than 100 F per day while making <br />the transition into and out of spilling. <br /> <br />Figure 2: River Temperature at Wigwam Club <br /> <br />River Temperature at Wigwam Club <br /> <br />80 ~~~, ~. ~ <br /> <br /> <br />it <br /> <br />LL 70 ~ <br />UI <br />m 60 <br />... <br />t>> <br />4) 50 ~ <br />-c rtii <br />s: 40 <br />a- <br />E 30 <br />CD ~~ ~ <br />I- 20" ~.' <br />t-..... f'.. <br />~ ~ <br />~ ~ <br /><.0 (0 <br /> <br /> <br />......... <br />~ <br />~ <br /> <br />........ <br />~ <br />r:::: <br /> <br />~ <br />~ <br />se <br />I'- <br /> <br />l' <br />m <br />0: <br /> <br />,.... <br />i:::: <br /> <br />........ <br />~ <br /> <br />~ <br />~ <br /> <br />I' <br />~ <br /> <br />,.... <br />r::: <br /> <br />"" <br />~ <br />~ <br /> <br />........ <br />~ <br />~ <br />r...... <br /> <br />f'... <br />a <br />~ <br />I' <br /> <br />r-..... <br />Q? <br />t: <br />CD <br /> <br />~ <br /> <br />~ <br /> <br />~ <br />m <br />.......... <br />...- <br />~ <br /> <br />Date <br /> <br />d. Managing Peak Streamflows <br /> <br />Rainbow and brown trout are not native to the South Platte River and can have difficulty <br />reproducing in the naturally low wintertime streamflows and high spring runoff. High <br />streamflows, although naturally occurring, may negatively impact the recruitment of <br />young fish into the population. High streamflows can also negatively impact rainbow <br />trout spawning and redd success rates if streamflows remain high during spawning <br />activities (redd selection process) then decrease during post-spawning and leave redds <br />dry. However, high streamflows are also periodically necessary in order to maintain <br />channel stability and capacity, and to transport fine sediment downstream. Therefore, <br />flows will be managed, when possible, to attenuate peak flows during some years to <br />benefit fish recruitment, while some peak flows during other years will be passed, when <br />possible, for channel maintenance. As part of the annual operating plan, the participants <br />will determine whether to attempt to provide a channel maintenance flow during spring <br />runoff or attempt to attenuate peak flows to enhance fishery recruitment. The goal will be <br />to maintain successful year-class recruitment for brown and rainbow trout populations at <br />least once every three years. <br /> <br />Spinney, Eleven Mile and Cheesman reservoirs are not designed, sized, or operated for <br />flood controL Large amounts of additional storage would be necessary to manage the <br />naturally high runoff in the South Platte. Typically at the start of runoff, Cheesman <br />Reservoir has had approximately 10,000 to 30,000 acre-feet of space to filL In wet years, <br /> <br />N :\Supply\ Waage\wHdscen\attachb.doc <br /> <br />B-13 <br />