PA Aquatic Resource Restoration Conference 2026: Past, Present and Future

Over the past two centuries, Pennsylvania landscapes have been altered so drastically that it can be difficult for stream restoration practitioners to have a sense of what changes likely took place in given watershed they may working in. Watershed alterations for agriculture, urbanization, and natural resource extraction (timber, oil, natural gas, gravel, and coal mining) are the dominant reasons for these alterations, but their timing, extent, and impact on the fluvial system varies considerably. 

 This presentation provides an overview of nine historic alterations to watersheds and how they varied regionally since colonization began in the 17th century. It also provides an historic overview of over 5,000 stream restoration projects completed across Pennsylvania in the past century and assesses the extent to which mitigating legacy alterations were considered by watershed managers and practitioners in their restoration plans and designs. This becomes increasingly important as watershed conservation and stream restoration practices continue to evolve from traditional form-based approaches to practices aimed at reestablishing physical, chemical, and biological processes that are needed to sustain river and floodplain ecosystems.