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conditions, especially in the last four years of drought: resulting; in a much longer growing season, and less natural precipitation during that growing period. The requirements varied from 80 acre-feet in 1981 (1.46 acre-feet per acre) to 138 acre-feet iri 2000 (2.52 acre-feet per acre). The crop irrigation requirements aze summarized monthly in Table 5. Historic Consumptive Use The methodology remains unchanged from the original study. The historic consumptive use for 1971 through 2003 averaged 53.3 acre-feet per year (49 percent of the crop imgation requirement) and ranged from 0 acre-feet several years to 116 acre-feet in 1996. The average annual historic consumptive use for the 1971-2003 period was 27.8 percent of the average annual diversions, dropping to 26.9 percent for the 1984-2003 period from 29 percent for the 1971-1984 period. The historic consumptive use for 1971 through 2003 is shown in Table 6. It is understood and assumed that the agreement acknowledging historic use from 1928 through 1984 continues in effect, and that the belief regarding use in the 1928 through 1971 period is still valid. Therefore, the historic consumptive use of the Home Ditch for 1928 through 1984 averaged 87.0 acre-feet per year (87 percent of the crop irrigation requirement), and the historic consumptive use of the Home Ditch for 1928 through 2003 averaged 77.8 acre-feet per year, or 75 percent of the crop irrigation requirement, a significant drop. Carrier Water There aze no changes suggested to the recommendations of the original study, and no significant difference in the diversion on the Home Ditch, except for that water diverted into Groundhog Reservoir per the agreement with MVIC in 2001-2003, and the proposed storage of water by DWCD from 2004 on, for purposes of meeting consumptive use from the mining operations and the new ponds when the Home Ditch is not in priority. The recent improvement of parts of the Home Ditch by installing pipe may reduce the 2.26 cfs carver water required in the future, and the holding of excess water by MVIC and/or DWCD for release during the non-imgation season may negate the need to have 0.25 cfs (for stock water and domestic water right) held in trust by DWCD. CONCLUSIONS AND RECOMMENDATIONS There are no significant changes from the original study: 1. The Home Ditch has historically been used to irrigate a total of 54.7 acres of hay and grass pasture. Some of this has been voluntarily dried up to provide replacement water for water consumed by mining operations, subject to a substitute water supply plan beginning in 2001. 2. The crop irrigation requirement for 54.7 acres of hay and pasture grass averaged 107.5 acre-feet per year (1.97 acre-feet per acres) :for 1971 through 2003, and ranged from 79.9 acre-feet in 1981 (1.46 acre-feet per acre) to 138 acre-feet per acre in 2000 (2.52 acre-feet per acre). 3. The historic water diversions, as shown in the State Engineer's records, averaged 191.8 acre-feet per year for 1971 through 2003, and ranged from 0 acre-feet in ten years to 563.2 acre-feet in 1985.