LCMS Land Cover Comparison (1985 vs 2024)

Between 1985 and 2024, Salt Lake County experienced a significant transition in land cover, characterized primarily by the expansion of developed surfaces and the contraction of natural grasslands and water bodies. The most prominent trend is the near-doubling of Barren or Impervious surfaces, which rose from 18.25% to 33.02% of the total land area. This increase represents a substantial conversion of the landscape into built environments or non-vegetated states.

This urban expansion occurred largely at the expense of the Grass/Forb/Herb category, which saw a decline of approximately 10 percentage points, falling from 25.18% in 1985 to 15.10% in 2024. Additionally, Water cover decreased significantly, dropping from 9.19% to 3.75%. While these classes saw major reductions, the Trees classification remained the most stable dominant land cover, showing a slight increase from 32.56% to 33.71% over the 39-year period.

Spatial analysis of the imagery highlights the following geographic shifts: * Urban Expansion: The 2024 frame shows a significant outward migration of the urban core (maroon). Development has moved south and west, infilling areas that were previously dominated by grasslands (light yellow) in the 1985 baseline. * Hydrological Recession: In the northwestern portion of the county, the recession of the Great Salt Lake is clearly visible. The 1985 extent of water (bright blue) has been replaced by a mix of barren land and shrubs in the 2024 frame. * Montane Stability: The eastern mountainous regions, characterized by dense tree cover (dark green), remain the most consistent spatial feature across both time steps, showing minimal encroachment compared to the valley floor.

LCMS Land Use Transitions (1985 to 2024)

Between 1985 and 2024, Salt Lake County experienced a significant expansion of developed land, which grew from approximately 20.6% to 33.1% of the total land area. This increase was primarily driven by the conversion of agricultural and rangeland classes. While 20.03% of the county remained developed throughout the study period, an additional 13.11% of the landscape transitioned into the developed category from other land uses.

The conversion of agricultural land represents the most substantial proportional shift. Of the land classified as agriculture in 1985, only 1.48% remained in production by 2024, while 6.49% transitioned to developed surfaces. Rangeland and pasture also served as a primary source for urban expansion, with 5.82% of the total county area shifting from rangeland to developed land. Together, the loss of agricultural and rangeland areas accounted for 12.31% of the 12.5% total increase in developed acreage.

Other land cover classes remained comparatively stable or contributed minimally to urban growth: * Forest: Remained the most stable class, with 29.84% of the county area persisting as forest. Only 0.53% of forest land transitioned to developed use. * Rangeland Persistence: Despite losses to development, 14.48% of the county remained rangeland or pasture. * Other Transitions: Approximately 3.47% of land classified as "Other" in 1985 transitioned to rangeland by 2024, while 1.81% of 1985 agricultural land shifted to rangeland.

In summary, the data indicates a near-total conversion of 1985 agricultural lands, with the majority of those areas, alongside significant portions of rangeland, being absorbed into the developed urban footprint.