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is activated all juniors will be shut off to the extent necessary to the instream flow amount appropriated. Example: Assume the lowest 10 consecutive total flow volume for April is 1,235,919 af (2077 cfs). Subtracting the first level development allowance for April of 20,827 (35 cfs\day * 1.9835 * 30 days * 10 years) yields an "April instream flow call trigger" of 1,215,092 af. We can now look at the 10- year running total discharge volume for April to determine when a call should be placed. If the 10-year running total discharge volume falls below 1,215,092 af a call would be placed against all upstream junior water users for all available flow necessary to satisfy the appropriation. For April 1990, no call would have be placed. REMAINDER OF YEAR: During the remainder of the year, August through March, a 1O-year running total for the "lower limit of total consumption" allowance for each month would be subtracted from a 10-year running total volume of the Service's flow recommendation for each corresponding month. The result becomes the "monthly instream flow call trigger" for determining whether or not a call would be placed either during the following month or in the corresponding month of the following year. In other words, during the remaining months, whenever the 10-year running total flow volumes are less than the full CWCB instream flow appropriation volume for a equivalent 10-year period (flow recommendation volume less the "lower limit of total consumption" monthly allowance volume) a call for administration would be made. Additionally, whenever there is a modification to the Paragraph 4 portion of the water right, there must be corresponding adjustment to the monthly instream flow call triggers. Example: Subtracting the August "lower limit of total consumption" allowance of 72,556 af (118 cfs\day * 1.9835 * 31 days * 10 years) from the Service's wet year (20% exceedance) August flow recommendation of 319,740 af (520 cfs\day * 1.9835 * 31 days * 10 years) yields an "August instream flow call trigger" of 247,184 af. We can now look at the 1O-year running total flow volumes for August to determine if a call should be placed. The August 1990 10-year running total flow volume is 266,245 af, which is more than the "August instream flow call trigger", thus, there is no river call. 2. The Division Engineer must track gaged flow in order to compute the 1O-year running total flow volumes and determine whether or not a call should be placed. 3. The decree will defme the "monthly instream flow call triggers", Paragraph 3 and 4 water and how to modify them. Generally, large modifications should result in changes to both the instream flow appropriation and the call trigger, while small modifications may only result in changes to the call trigger. 11-4