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Augmentation Plan Operations <br />Lagged well depletions represented in depletion Plan structures will be replaced via operating <br />rules using natural flows in priority, lagged accretions from canal seepage and recharge pits, and <br />from other sources, depending on the augmentation plan. <br />1. First, the replacement demand will be met "in priority" by natural river flows on days when <br />the downstream call is junior to the well depletion Plan priority or there is no downstream <br />call. Well depletion Plan priorities should be established based on the available information, <br />in the following order of precedence: <br />- Total depletion and common priority date used to administer the plan (see <br />Appendices). <br />- Specific depletion and ground water right priorities of wells in the Plan. <br />- Total depletion and the most junior ground water right priority of all wells in the Plan. <br />2. Second, the replacement demand will be balanced with accretions calculated for the canal <br />seepage and recharge accretions Plan structures. <br />3. Third, the replacement demand will be met from other sources (e.g., reservoir releases, <br />bypass of ditch water rights, augmentation wells, etc.). <br />An example augmentation plan accounting is included below: <br />1. A well with a 1956 priority ground water right pumps 100 ac-ft (at 80 percent efficiency) in <br />April to meet an irrigation demand of 80 ac-ft. <br />2. The well is located such that the lagged depletions to the river from pumping and lagged <br />accretions to the river from inefficiencies occur in equal amounts in April and the next three <br />months as follows: <br />Month April May June July Total <br />Lagged Pumping Depletions 25 25 25 25 100 <br />Lagged Accretions 5 5 5 5 20 <br />Net River Depletions <br />(Augmentation Plan demand) 20 20 20 20 80 <br />3. Administration of the augmentation plan is based on the ground water right priority that <br />resulted in the river depletion. Therefore, if the "call" on the river is junior to 1956, the <br />augmentation plan demand is met by natural flows in priority. <br />4. If the 1956 well right is out-of-priority, the augmentation plan demand is balanced (met) by <br />available river accretions associated with diversions to recharge under the plan or met by <br />other sources associated with the plan.. <br />COMMENTS AND CONCERNS <br />Well augmentation plans were tabulated based on review of the 2001 GIS Irrigated Acreage <br />Assessment and well ID-augmentation plan ID associations in HydroBase (Version 20060816). <br />Decrees for 12 augmentation plans and applications to the Division 1 Water Court were reviewed <br />along with information from HydroBase and augmentation plan representatives. Summaries of <br />the demands, supplies, and operations of the largest well augmentation plans are provided in the <br />Appendices. Recommendations regarding demands, supplies, and operations are provided for <br />representation of the smaller well augmentation plans in the SPDSS Surface Water Planning <br />14 of 16 <br />