BOARD00312

• Board Meeting Date: 3/21/2006
• Description: ISF Section - New Appropriation Recommendations in Water Division 4
• Board Meetings - Doc Type: Memo

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North Fork Gunnison
1/18/2006
Page 3

Populatioll a1lalysis
Population and population density of each subbasin were calculated from 2000 census TIGER
data. Seven census trdcls overlap the subbasin boundaries (census tracts (963600, 963800,
963900,964600, %-1900, %5000, and 966200). These seven census tracts contain a portion of
ten municipalities (Crawford, Crested Butte, Delta, Gunnison, Hotchkiss, Marble, t-.tount
Crested Butte, Paonia, Pitkin, and Olathe). To obtain an accurate population distribution,
population densities were calculated for incorporated and unincorporated portions of each
census tract separately. It was assumed that no people live on public land. Landuse was
divided into public or private land, and population density was calculated based on the total
area of private parcels within that census tract.

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The incorporated area populdtion densities were calculated by dividing the populdtion of the
municipality by the area of private land (obtained from the land use parcel coverage) within
that municipality. Unincorporated population density for each census tract was calculated by
subtracting the municipality population within that census tract from the total population,
and dividing that figure by the area of private land use within the unincorporated portion of
the census tract. Population densities for each private parcel within
incorporated/unincorporated areas of a census tract were assigned. The population densities
and private land area within a subbasin were used to calculate the population within each
subbasin and a weighted average population density, shown in Appendix A.

Results
Projected population estimates
Population growth rates, defined as the percent difference between the 2030 and 2CKJO
population estimates, were calculated for Delta, Gunnison, and Montrose Counties, using
DOLA preliminary population forecast estimates. Calculated population growth rates are
107%,45%, and 108% for Delta, Gunnison, and Montrose Counties, respectively. To be
conservative, the maximum population growth rate of 108% was used to estimate 2030
population for each subbasin (Table 1), regardless of county. This results in a significant
increase in estimated population increase for Gunnison County, since a 108% growth rate was
used rather theln the OOLA projection of 45%.

Table 1 - North Fork subbasin population estimates

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Area {acres) 2000 2030 Population
Subbasin ocnulation nODulation Increase
Anthracite Creek 65,490 34 71 37
Coal Creek 62.243 5 10 5
Mud~Creek 154.263 904 1.880 976
Muddv Creek Crawford) 15,499 345 718 373
North Smith Fork 21.044 148 308 160
South Smith Fork 9,645 68 141 73

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