VDOT MS4 Permit Program Support Services

WSSI has provided comprehensive environmental engineering services to VDOT since 2010 for MS4 Permit Program Implementation Support, both as contract lead and as a subconsultant.

The Challenge

VDOT – working on their initial MS4 General Permit – had the daunting challenge of applying the Permit intent to Virginia’s entire road network. They needed a reliable, experienced consultant to help develop and implement their MS4 program from the ground up.

Our Solution

Creative problem solving has been a hallmark of our MS4 collaboration with VDOT. Implementing such an encompassing program in the country’s third-largest state-maintained highway system takes innovation, flexibility, and a deep understanding of the subject matter and the agency processes and operations. We piloted interactive databases for real-time field operations, delivered custom training to VDOT staff, and coordinated the essential agency standards and specifications to ensure that VDOT could effectively operate a comprehensive MS4 program that meets EPA requirements.

We started – partnering with VDOT – by assessing priorities and establishing goals for the program. Our staff recommended working first where VDOT’s MS4 intersected existing MS4 municipalities (urbanized areas) to establish comprehensive permit compliance practices. We developed required programmatic documents for VDOT, including manuals to ensure standardized methodology for outfall mapping, illicit discharge monitoring, BMP evaluation, TMDL compliance, inspection protocols, and O&M practices.

Our work has evolved with the program since 2010, and has included:

Stormwater BMP Rehabilitation and Improvement: Engineering evaluation of failing post-construction stormwater facilities to determine cost-effective rehabilitation; provided recommendations and cost estimates for retrofits and long-term maintenance.

Program Manuals and Training Materials: Assisted VDOT with development of numerous Erosion & Sediment Control (ESC) and Stormwater program manuals for use by VDOT and outside contractors. Manuals included Good Housekeeping and Pollution Prevention, BMP Inspection, BMP Maintenance, Illicit Discharge and Detection Elimination (IDDE), and Field Guides for Outfall Inspections.

Construction Inspections: Performed statewide annual QA/QC construction inspections for MS4 program compliance, assessing required documentation, implementation, and site-specific issues. Results were used to improve compliance at each site and programmatically, identifying needs for additional training, clarification, or guidance documents to support consistency across the program.

Outfall Inventory and Database Development: Developed an ArcGIS online application for an outfall inventory, including BMP outfalls. Performed field investigations and mapped 5,000+ outfalls. In locations where VDOT was assigned a Wasteload Allocation (WLA), WWSI trained VDOT staff in pollution prevention protocols.

MS4 Program Compliance Audit: Audited VDOT’s MS4 program across the Commonwealth in accordance with the EPA’s MS4 Program Evaluation Guidance. The evaluation included document review, staff interviews, and field inspections. Audit related services included a pre-audit that was conducted prior to EPA’s official audit, and technical support and liaison with EPA during the official audit. This process allowed VDOT to identify program deficiencies and mitigate them prior to the EPA audit.

TMDL Development and Implementation Technical Assistance: Represented VDOT during development and implementation of TMDLs in the Chesapeake Bay watershed and others. Analyzed the implications and costs for VDOT; developed technical comments on the draft Watershed Implementation Plans and draft TMDLs along with response strategies. Represented VDOT at Stakeholder Advisory Group meetings and provided comments through the Regulatory Advisory Panels for the new VSMP General Permits for small MS4s and for construction.

TMDL investigations: VDOT has WLAs assigned for eight TMDLs. We outlined and prioritized the processes necessary to ensure compliance. Performed field investigations to locate outfalls and collected land use and imperviousness data about VDOT’s right-of-way. Developed a model estimating the amount of total volume stormwater discharged and the total loading of pollutants, using several industry-accepted models, including HSPF, L-THIA, STEPL, and WTM.

Run-off Reduction Based Criteria Training Workshop: Provided two day-long training modules to educate VDOT staff, including design engineers, hydraulic specialists, and environmental staff on the VDOT MS4 program, the new Virginia stormwater management regulations, and VDOT right-of-way stormwater run-off and water quality. Addressed BMPs, pollution prevention, illicit discharges, proper waste disposal, and hydraulic design considerations relative to WLAs and TMDLs.

DEQ Stormwater Management Training: Through a Memorandum of Understanding (MOU) with VDOT and DEQ, provided DEQ’s stormwater management classes to more than 700 VDOT staff and contractors seeking certificates of competence in program administration, SWM plan review and SWM inspection.