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35 The combination of increased storage capacity and reduction of losses will result in increased diversions of about 4,000 acre feet per year, on the average. It should be noted that Grand River Ditch can provide a more nearly constant supply to the east slope than can a new structure dependent upon east slope water resources. Although snowmelt runoff on both sides of the Divide is characterized by large annual fluctuations, a new canal or reser- voir diverting from the Poudre would have new water available to it for periods ranging from one to six weeks in the years of exceptionally high runoff. The Grand River Ditch, in contrast, can supply additional water :i Ii. e'(ery :'ye~r ..by cons t ruc t i on of the add it i ona 1 rese rvo i r capaci ty and lining of a portion of the Ditch. The average opening date for Grand River Ditch is the middle of May, after a month or six weeks has been spent in clearing the Ditch of snow, and, in some areas, of earth sloughs. The high leakage rate in reaches of the Ditch increases the difficulty of snow clearing. There are reaches of the Ditch where snow removal is not greatly, at present, aided by the flushing action of water running in the Oitch because the flow leaks away. Lining in such reaches would provide a running ditch to erode and flush the snow. , The benefits to Irrigators under the Larimer County Canal of increased diversions by Grand River Ditch can be seen in Table IV-C. If 1 Because the Cache la Poudre is a managed stream wherein all ditches benefit from the system of exchanges, additional imports and additional upstream storage will increase exchange potentials, and be of benefit to the basin generally. Also, increased flows high up on the Poudre will increase the physical water availability for exchange to future reservoirs such as Idylwilde. WATER QUALITY The quality of water diverted by the Larimer County Canal, representing all sources, is shown in Table IV-G. While the actual quality of Grand River Ditch and Long Draw Reservoir is somewhat better, the ~pter . is commingled with other sources during its period of transportation in the Poudre River.