Land Cover changes for each Hydrologic Unit

The water quality in the streams, rivers and lakes of any watershed is closely tied to the watershed’s land use and the land cover.  The 2018 Land Cover analysis performed for LJEA used the National Land Cover Database for 2001 and 2011.  The land cover was tabulated for each of the 11 Hydrologic Units that comprise the Lake James Watershed. A map showing those HUs is here. The National Land Cover Database assigns one of fifteen different land cover classifications to every 30 meter by 30 meter area within the watershed for each of the two years.  The land cover classifications and the tabulations for each HU are presented in this spreadsheet.  

To aid the reader in quickly understanding the data, the following discussion groups the 15 classifications as follows:

  • Developed consists of Developed Open Space, Low Intensity Development, Medium Intensity Development, High Intensity Development and Barren (usually rock, sand, pavement and other hard surfaces).
  • Forest consists of Deciduous Forest, Evergreen Forest and Mixed Forest.
  • Agriculture, Grassland & Shrub consists of Shrub/Scrub, Grassland/Herbaceous, Pasture and Cultivated Crops.
  • Other consists of Woody Wetlands and Emergent Herbaceous Wetlands

There are four Hydrologic Units that have Forest exceeding 90% of their land area (Curtis Creek, Buck Creek, Armstrong Creek and Lower Linville).  There are five HUs that are under 8% Developed (Crooked Creek, Curtis Creek, Buck Creek, Armstrong Creek and Lower Linville). Predominantly forested areas and areas with a low percentage of developed land generally provide the highest quality water in the Lake James Watershed.

There are two HUs that have greater than 15% of their area classified as Developed (Tom’s Creek and Upper Linville). There are five HUs that have Agriculture, Grassland & Shrub classifications exceeding 10% of their area (Crooked Creek, Mackey Creek, Tom’s Creek, Catawba/Lake James, and Upper Linville). High levels of Developed land and Agricultural use is often associated with water quality degradation. LJEA plans to develop biological, chemical and physical monitoring plans to address potential adverse water quality impacts originating in these areas. In addition, more developed areas are likely to have industrial and domestic waste discharges directly to their streams. More information about the point source discharges in each HU of the Lake James watershed can be found at the North Carolina Watershed Stewardship Network website.

The changes in land cover between 2001 and 2011 are shown for each individual HU in the maps below.

Headwaters Catawba River

Curtis Creek

Crooked Creek

Mackey Creek-Catawba River

Buck Creek

Tom’s Creek-Catawba River

Armstrong Creek

North Fork Catawba River

Lake James-Catawba River

Lower Linville River

Upper Linville River