Land use change has significant impacts on watershed hydrology because an increase in impervious/urban areas changes water quantity and quality on a variety of spatial and temporal scales. Urban areas are an important source of runoff and non-point source (NPS) pollution, and NPS pollution is the leading cause of water quality degradation in the US. Traditional hydrologic models focus on event-specific estimation of peak discharges and NPS pollution. Although these are appropriate for short-term, local scale surface water management problems, they are of limited value for attempts to understand the long term hydrologic impacts of land use change. A Long-Term Hydrologic Impact Assessment (L-THIA) model has been developed and expanded, [...]
