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<br /> ' <br />Recommendations winter flows <br />A key flow consideration during the winter should be maintaining natural ' <br />conditions of annual variability and steady discharge with little fluctuation <br />during the mid-winter period. Flaws levels may be different from year to year <br />doing into the winter period depending on the snowpack the previous winter and <br />fall precipitation. However once winter sets in, flows have been historically <br />stable during midwinter (Figure 22). In addition, any proposed alterations <br />in flows during the winter should be analyzed with respect to the portion of <br />the winter in which they may occur. Effects will be different due to current <br />, <br />,ice conditions, air temperature, precipitation, and discharge. Reductions <br />lbelow natural baseflow at initial ice formation should be avoided. At this <br />time actual discharge is already decreasing because water is being tied up in j <br />ice formation. Maintaining natural flaws during the initial freeze period in <br />late November or early December would insure that ice cover forms over the <br />maximum amount of usable winter habitat in a given flow year. A key flaw <br />consideration during mid-winter is maintaining the natural conditions of <br />rsteady discharge with little fluctuation. Flows normally do not fluctuate <br />more than 140 cfs above or below the annual mean during,.the period from mid- <br />December through February (Figure 22). It is important to avoid unnatural <br />Idischarge fluctuations that could remove natural ice cover. Overall system <br />productivity will probably be best maintained by providing adequate water <br />levels in a variety of low-velocity habitats (embayments, backwaters, pools <br />and runs) that squawfish utilize during the winter. During Winter 2, this <br />versity appeared to be best maintained in the 200-300 cfs flow range during <br />e mid-winter period. Flaws below this range would result in less than <br />depth in preferred embayment habitat, while hider flows flood and <br />optimm <br />' <br />eliminate these habitats. The ice-out period, which usually occurs in March, <br />can be the most critical part of winter. During this time, water surface <br />elevations and effective depthdecrease even though discharge is maintained. <br />Therefore, any reductions in flaw sha ld be avoided until ice is completely <br />out.. <br /> <br />t <br />t <br />I- I <br /> <br /> <br />60 1 <br />t