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<br />when well pumping increases. Also, water levels decline during years of low <br />precipitation such as 2002 and are higher during wetter periods such as 1997 and-1998. <br />The hydrographs for the wells in the vicinity of the recharge pond show much larger <br />changes in the water levels than the wells farther south of the recharge area. For <br />example, the hydrographs for Well Nos. 12, 13, and 14 show a decline in water levels in <br />late spring (a period of increasing water demands for irrigation but prior to the effects on <br />the aquifer from recharge) while the water table rises significantly in the late summer <br />months (while irrigation and well pumping demands are still high but the effects of <br />recharge are occurring). <br />The U.S. Geological Survey monitors the water table at the City's Well No. 21. The <br />monitoring program started in June 1964, and the depth to water is measured several <br />times per year. Appendix E contains a hydrograph of water levels and a table of the <br />data collected. <br />A brief recharge program was conducted in August and September 2006 at the south <br />recharge area. A rise in the water table is noted in late 2006 in the hydrographs for Well <br />No. 4 and several down-gradient wells. However, as discussed above, without individual <br />well usage, the water table response may be due to both recharge effects and reduction <br />of well pumping. <br />D. Operations and Accounting <br />The City operates its wells pursuant to a "Post 85 Rule 14 Plan" annually approved by <br />the State Engineer. The Plan envelops the plan for augmentation decreed in Case No. <br />W-4015 and other augmentation sources. These other augmentation sources include: <br />1. Deliveries to the Clay Creek recharge site of water derived from the City's <br />ownership of Fort Bent Ditch shares that are not included in Case No. W- <br />4015, <br />2. Deliveries to the Clay Creek recharge site of the Ciry's Project water, <br />3. Return flows derived from the City's wastewater treatment facility and from <br />septic tank/leach fields, <br />4. Return flows derived from distribution system losses, and <br />5. Return flows derived from irrigation of residential and public lawns and <br />landscape. <br />On a monthly time step, the net well pumpage amounts (not covered. by Case No. W- <br />4015) are lagged to the stream and the depletions are offset by the direct delivery of <br />treated wastewater, lagged accretions from municipal irrigation, septic tank/leach fields <br />and system losses, return flow, and lagged accretions caused by recharge of Project <br />29 <br />