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Well Augmentation Subdistrict - Loan Feasibility Study Page 11 downstream water right call in every river reach. WAS must also project periods of prolonged severe drought conditions with respect to the yield of replacement water supplies. The projection concept, i.e., comparing future water supplies to future replacement obligations, is shown in Figure 7. 10,000 <--- -------------- -- - - -- Projection Period - --------------------- - - - - -> 9,000 8,000 Replacement Supply (dry -year yield) 7,000 — Replacement Obligation (100% senior call) Q 6,000 E 5,000 0 c 4,000 3,000 2,000 1,000 0 . 2010 2011 2012 2013 2014 2015 2016 Year Figure 7: Limitations imposed by projection tool required by WAS decree. The WAS projection tool is used to establish the amount of additional ground water pumping that may be authorized each year after WAS fully replaces depletions caused by prior year pumping ( "post- pumping depletions "). The amount of additional pumping is referred to as the annual quota and is expressed as a percentage of the Class B, C, and D contracted water supply. For example, authorizing WAS constituents a quota of 10 percent allows WAS wells to pump an aggregate of approximately 2,000 ac -ft (0.1 * 20,400). It should be noted from Figure 7 that although there is a projected excess water supply in early years (2010 - 2012), there is a shortfall of projected replacement supplies in later years (2013 - 2016). The projected shortfall constrains the projection tool and restricts or prevents WAS from authorizing additional well pumping. In reality, the shortfalls are more than made up by additional water rights acquisitions, on -going recharge efforts, and new short -term leases that become available in future years. In addition, the actual yield of water supplies probably exceeds the allowed projection yield that is based on extreme drought, and actual call conditions are significantly less restrictive than represented in the projections (but required by the WAS Decree). Projection requirements of the Decree have prevented WAS from authorizing any pumping since 2005, i.e., 100 percent curtailment. NEED FOR ADDITIONAL WATER SUPPLIES As discussed above the WAS Plan is operated according to six reaches of the South Platte River and its tributaries. All of the water supplies owned by WAS are located within or below Reach C of the Plan, i.e., below the headgate of the Western Mutual Ditch. Replacement obligations upstream of the Western Mutual Ditch have been met in recent years largely through relatively short -term lease LeonardRice ENGINEERS,INC.