Laserfiche WebLink
<br />OI'''~8'1 <br />U.LO '. <br /> <br />upstream reservoirs are called upon to supply additional water. <br />Reservoirs that can be used to supply additional water include the <br />reservoir that is in the same reach of the demand, if it is upstream of <br />the demand, plus any upstream reservoirs specified in the input control <br />file as being able to supply additional water to the demands in this <br />reach. If a demand is in need of additional water, these reservoirs are <br />ranked in descending order by the size of their current surface areas. <br />The reservoir with the largest surface area then supplies additional <br />water until either the demand is satisfied or the reservoir reaches <br />minimum active capacity or maximum ~l1owable release. If additional <br />water is still needed, the next ranked reservoir is called upon, and so <br />on until the demand is met. If the demand cannot be fully met, the <br />demand is shorted and a shortage message is printed. <br /> <br />~ <br /> <br />The third type of sequence point is the reservoir. Each reservoir has <br />a set of monthly target content values called rule curves. These values <br />are read in from the CRSM control file. In addition, the rule curves <br />for Flaming Gorge, Blue t-lesa, Navajo, Powell, and Mead are adjusted <br />monthly based on conditions in the system. These rule curves and <br />adjustments are further described in section 11.2. When a reservoir <br />sequence point is processed, the attempt is made to bring the reservoir <br />contents to these target contents level. The first step is to add the <br />flow in the river at the previous sequence point to the current contents <br />of the reservoir. Next, the reservoir release is increased or decreased <br />to force the contents, with the inflow added in, to meet the target con- <br />tents. Finally, the release and contents are checked against minimum <br />and maximum values and adjusted if necessary. The release becomes the <br />new flow in the river. It should be noted that Lakes Powell and Mead <br />use special methods for determining releases and are discussed <br />separately in section 8. After the release and contents are determined, <br />a new water surface elevation and area, evaporation, bank storage, and <br />power yeneration are computed. <br /> <br />, <br />" <br />I, <br />, <br /> <br />~ <br /> <br />!. <br /> <br />A numerical example of how water is routed through a reach is given in <br />fi gure 7.2. <br /> <br />Salt in the river is routed through the system similarly to the proce- <br />dure of routing water. Salt is added to the river at inflow points, <br />diverted from the river at demand points, and mixed into reservoir con- <br />tents. The procedure is described in more detail in section 10. <br /> <br />32 <br />