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<br />O~3J93 <br /> <br />Much work needs to be done between now and the completion of the Regional <br />Plan. Between now and then, you will have ample time to review and <br />comment on our work. As always, your concerns and suggestions are <br />welcomed at any time without special invitation. <br /> <br />FOREST PLANNING <br /> <br />. <br /> <br />Now let's look at National Forest Planning. Each Forest Service Region <br />has designated a lead forest to devise and test a planning process <br />suitable for the complexity of the management situation and within the <br />requirements of various laws and regulations that govern our operations. <br />The Arapaho and Roosevelt National Forests have the lead forest assignment <br />for the Rocky Mountain Region. <br /> <br />The draft Arapaho and Roosevelt plan analyzed 112 prescription-size water- <br />sheds. These are watersheds drained by 4th and 5th order stream segments. <br />A new watershed computer analysis model titled HYSED was developed and <br />used to analyze each drainage for water and sediment production by each <br />of five management alternatives considered. It was determined that the <br />Arapaho and Roosevelt have increased water yield above baseline by an <br />estimated 61 thousand acre feet above an assumed natural baseline con- <br />dition. The range of water yields varied from a 4,000 acre feet increase <br />while meeting a minimum level of protection and use, to a nearly 10 thousand <br />acre feet increase under a high sustained yield of commodity and non- <br />commodities option. Sediment production increases also varied roughly <br />in relation to the water yield increases, but the relationship is not <br />linear, The range varied from 1780 to 5500 tons of increased sediment <br />per year. <br /> <br />These figures are estimates of effects of alternative treatments the first <br />year after treatment. On a sustained basis, this year's effects decrease <br />each year during a recovery period of variable length, but the cumulative <br />effect increases each year until the recovery of the first year's treat- <br />ment is completed. After that time, the effects are static as long as <br />the treatments remain constant year after year. This means the low water <br />yield option of 4000 ac.ft.jyear would parlay over a conservative <br />hydrologic recovery period of 40 years to an,annual water yield increase <br />of 60 thousand acre feet from the Arapaho and Roosevelt National Forests, <br /> <br />The preferred alternative in the Arapaho and Roosevelt plan is expected <br />to produce an annual increase of 5500 acre feet of water. This closely <br />corresponds to a management strategy to produce an intermediate level of <br />production for a variety of outputs. <br /> <br />The 5500 acre feet water yield increase in the preferred alternative of <br />the Forest plan is 57% of what it could have been under a high water yield <br />alternative, but water was only one of the resources juggled in the <br />multiple resource mix. <br /> <br />C-5 <br />