The Manual is intended to be a tool to achieve the regulatory standard to protect, maintain, and improve the Commonwealth’s water resources through comprehensive site planning and BMP design guidance, while allowing for the continued growth and development of Pennsylvania. This guidance manual identifies information on resource planning, techniques for land development, and concepts and procedures for designing and implementing performance-based BMPs for managing stormwater for quantity and quality. The comprehensive planning approach to stormwater management emphasizes reducing the impacts of development activities through the mitigation process by employing practices that avoid and minimize potential impacts to watershed resources. The BMPs are designed to minimize or mitigate for the unavoidable impacts that development has on watershed resources.