Data Tables
Explanation
Trends in land and impervious cover provide insights into the changing environment of Thurston County over time. Satellite imagery from 1992 to 2021 reveals that over 14,000 acres of land were converted to low, medium, or high-density developed land covers, which is over 500 acres per year.
Forests cover over 50% of the county’s area. The forested area has fluctuated since 1992 as timber lands are cleared, replanted, and regrow. Grassland and scrub/shrub cover 12% of the county’s area and cultivated lands and pasture/hay cover 10%.
In 2021, approximately 6.5% of Thurston County was covered by impervious surfaces.
Impervious Surfaces
Impervious surfaces include roads, driveways, rooftops, and other compact surfaces that do not allow rain to infiltrate into the soil and groundwater. Watersheds with large areas of impervious surfaces tend to have more runoff, which increases erosion and washes pollutants directly into streams, lakes, and Puget Sound.
Sustainable Thurston Report Card
How do land cover and impervious surface affect the health of Thurston County's rivers and streams? Visit the Sustainable Thurston Report Card to learn more.
Sources
- NOAA Coastal Change Analysis Program (C-CAP)
- National Land Cover Database