Urban/suburban land use is the most rapidly growing land use class. Along with increased development inevitably comes increased impervious surface--areas preventing infiltration of water into the underlying soil. The extensive hydrological alteration of watersheds associated with increased impervious cover is very difficult to control and correct relative to the impact of urbanization on waterways. Development practices that reduce impervious area and include preventative strategies to protect water quality are more effective and less costly than remedial restoration efforts. Simple and reliable methods to estimate and project impervious cover can help identify areas where a watershed is at risk of changing rapidly from a system with relatively pristine streams to one with significant symptoms of degradation. In this study, a method for estimating and projecting impervious cover for 12 and 14 digit HUCs over a large area was developed and tested. These methods were then applied in EPA Region 4’s eightsoutheastern states to provide the Region with a screening tool to guide monitoring and educational efforts.