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season as it progresses. After the annual index supply forecasts for both riVers are established, then water rights are curtailed as is necessary to ensure that the Compact delivery r.quirement is met. If the actual runort; an~ summer thunderstorm activity change the forecast~d index s~~ply ~hen adjustm~nts .are. made to delIveries to account for those changes. Large late season mcreases mHhe mdexes requIre slgmficant changes in administration that can cause considerable hardship to very senior pre-Compact water rights. As described above, day-to-day administration of the Rio Grande COIbpact for inter- and intrastate purposes involves a series of detailed calculations using historical, real-ti/ne, and forecasted stream flow information at all seven of the Compact gages as well as the intermediate ~ages in between them. The upper index gages are: Rio Grande near Del Norte Conejos River near Mogote Los Pinos River near Ortiz (April- October) San Antonio River at Ortiz (April- October) The lower index gages are: Rio Grande near Lobatos Conejos near La Sauses (two stations) Flows at these locations are used to determine the total annual delivery obl!gation, to determine deliveries to date, and to establish a "curtailment" of water use if needed to meet the~elivery obligation of the year. The State Engineer, through the Engineer Adviser and the staff in the Divi~ion of Water Resources office in Alamosa, make these calculations every 10 days when diversions are b4ing made, and monthly during the remainder of the year for both river systems. It is critical to remem~er that each river is analyzed separately and that each river has its own delivery obligation. The general methodology for making these calculations is described in the lour following steps. The dates are for illustrative purposes only and vary depending on the forecast and,~ompact status of the State of Colorado. Examples ofthe 10-day analysis sheets and report are attached. ' January 1" through March 31" Both the Rio Grande and the Conejos River diversions are cuIjailed 100 percent, that is no diversions are allowed except for storage in pre-Compact res~rvoirs. Any storage in post- Compact reservoirs is accounted for and subject to Compact rule~:. Exception to the I 00 percent curtailment can occur if Colorado has a large accrued credit, a spi(t of Elephant Butte has or will occur or if drought conditions prevail and thus the anticipated obligation is very low. This action will maximize deliveries to the Stateline during this period and wl:1l allow for lower curtailment during the irrigation season. The Closed Basin Project is pumped fat a prudent level considering the limitations of winter operations and well production. The Match I forecast is used to make some of the initial analyses for how the Compact will be admini~tered for the early part of the irrigation season. The Rio Grande headwater areas typically receivp large accumulations of snow during this month and therefore it is normally assumed that signiJ!icant changes will be made to the projected index supply when the April forecast is received. . April 1" through October 31" Diversions are normally allowed to commence around April I bu{because of the normally cold springs and low demand, Compact obligations are usually made wilhout any curtailment. As soon as the April forecast is received from the Natural Resources Const{rvation Service (NRCS) on or