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obtain estimates of developable land, both currently irrigated and non-irrigated. In addition, population density, land use breakdowns and parcel sizes were examined. These data were used to estimate growth within municipal boundaries and redevelopment or subdivision of existing parcels. Ranges of land use densities were then used to estimate potential future water demands. . The assumptions that were used in this model were conservative in order to try and maximize development potential. The study results can be reviewed in the attached Memorandum from CDM entitled "Projected Consumptive Use Water Demands for the North Fork of the Gunnison instream Flow analysis, January 18, 2006." The second part of the analysis, conducted by Leonard Rice Engineering, incorporated the future consumptive uses developed in the first part of the analysis into an existing Colorado Decision Supoort System (CDSS) water planning model for the Gunnison basin. The model was then run under two different scenarios. The first scenario assumed that the proposed ISF rights would be junior to the proposed future demand, and the second scenario assumed the rights would be senior to the future demand. The model runs were then analyzed to estimate future shortages and augmentation requirements in each of the North Fork sub basins. The model results were provided on an average annual daily basis over the period 1975 through 2003. The model results can be reviewed in the attachment entitled "Executive Summary to the Water Availability Analysis in the North Fork of the Gunnison Basin", as well as in the attached Final Memorandum from Leonard Rice Engineers entitled "Water Availability Analysis in the North Fork of the Gunnison Basin, February 22,2006." Water availability for the original proposed ISF flow amounts, as identified at the January 2005 meeting, was determined by analyzing existing stream gaging records. Under these existing conditions, staff determined that water was available for the proposed recommendations. However, Staff utilized the model runs to perform a more in-depth analysis of water availability . and to determine if the proposed ISF rights would prevent future water development in the basins. In cases where it appeared that water was not available, staff modified the recommended flow amounts and/or time periods and had the model re-run to see if the impact on these future water rights could be reduced or eliminated. On the segments modified as a result of water availability, the Division of Wildlife was contacted to determine if the modified flow amounts would still preserve the natural environment to a reasonable degree. On the Muddy Creek near Crawford recommendation, the modeled results showed significant water availability problems even under existing conditions. On the Muddy Creek above Paonia recommendation there were water availability problems on the shoulder months and during the winter period. As a result, the flows were reduced in the winter, and the period for the summer recommendation was shortened. This modification resulted in a significant increase in future exchange potential above Paonia Reservoir. Before the modification, the shortage in exchange potential was 149 acre-feet. After the modification, the limitation to future exchanges was reduced to 32 acre-feet. Additional model runs indicated that this limitation could not be removed without significantly reducing the recommended flow amounts to a point where the natural environment would likely not be preserved to a reasonable degree. In general, the following conclusions can be made from the water availability analyses, discussions with the Division Engineer's office, and a review of new water right filings that have occurred over the past year. · Existing water rights and uses in the basins are senior to the proposed ISF rights and, as .. a result, the proposed ISF rights would not impact these existing rights or uses.