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municipalauthorities.org │ 49 of the draft PAG-13 permit that can be utilized strategically to meet the Volume Management Objective. Lessons Learned in Maryland: As Pennsylvania jurisdictions transition toward the new PAG-13 requirements, they find a ready- made blueprint just across the border. Maryland’s Phase II MS4 permit has functioned as a successful proof of concept for impervious area restoration and volume management planning, establishing a lifecycle that mirrors Pennsylvania’s emerging standards from initial baseline assessments to long term maintenance and credit tracking. The success of Maryland permittees proves that while the Draft PAG-13 requirements are challenging, they are entirely achievable through structured planning and standardized processes. By leveraging Maryland’s established framework and expertise, Pennsylvania can bypass the typical "growing pains" of a new regulatory cycle and move straight toward surpassing restoration goals. Methodology in Practice Providing comprehensive assistance to Maryland permittees involves the strategic development of their restoration programs, including baseline development and project planning and prioritization. A refined 5-step process is utilized to ensure successful MS4 program delivery. This methodology has been used across Maryland and can be applied to municipalities in Pennsylvania to meet and exceed MS4 permit compliance. Impervious Area Baseline Development Similar to the first step in the PAG-13 MEP Calculator, the first step is to conduct a baseline impervious area assessment, determining the amount of untreated impervious area within the urban boundary that is the legal responsibility of the permittee. Then, a comprehensive GIS analysis is performed, excluding impervious area from parcels owned by state or federal agencies, as well as those governed by independent NPDES permits, such as industrial discharge authorizations. The process also includes removing the volume and impervious area of existing stormwater facilities from the baseline requirement. Restoration Goal Calculation The refined baseline is then used to calculate the restoration goal, defined as the total impervious are restoration requirement or volume management objective required for treatment over the duration of the permit term. Project Planning and Prioritization After calculating the restoration goal, the next step for permittees is to conduct watershed assessments, identify potential project locations, perform field visits, and conduct feasibility studies. The resulting potential projects are then evaluated in a priority matrix which considers cost and credit, among other parameters such as environmental permitting requirements, access, property owner impacts, and more, to inform a priority list of projects for further investigation. The matrix can be customized for each permittee to capture preferences regarding BMP/SCM type or location. Following this ranking, high-priority sites undergo a feasibility study to validate the initial concept. The feasibility study provides a deeper technical dive into site constraints including access, utility conflicts, and topography, in addition to Regulatory article continued from page 35.