Impervious cover (IC) is a known stressor on stream ecosystems. Riparian buffer areas can help mitigate some of the impacts of urbanization. This chapter examined the effects of spatial resolution of IC data in the riparian zone and evaluated the influence of buffer type on IC estimates. Fixed-width and elevation-based riparian buffers were applied. Percent IC was obtained from the National Land Cover Database (NLCD) and compared to a high-resolution imagery analysis from National Agriculture Imagery Program (NAIP) data within the buffer zones. The study revealed that buffer type had minimal impact on percent IC, except in areas of unconstrained valleys, where there were notable differences between fixed-width and elevation-based buffers. These results suggested that while there is a trend toward the NLCD underestimating IC at lower levels of development, it may be adequate for mapping IC in the riparian zone for water quality studies, depending on the land use and land cover characteristics of the catchments being studied.