Municipal Separate Storm Sewer System (MS4) Program Support

Compliance & Permitting - Updating the Storm Water Management Plan and the Pollution Prevention Plans

Project Overview


The Montana Department of Transportation (MDT) holds a Montana Pollutant Discharge Elimination System permit for storm water discharges from Small Municipal Separate Storm Sewer Systems (MS4s), such as storm drains, pipes, and ditches. These Small MS4s are designed to gather stormwater and discharge it into local streams and rivers. To help MDT ensure regulatory compliance for this storm water discharge system, Weston is assisting with the development and implementation of a stormwater management program to reduce the discharge of pollutants, such as fertilizer, trash, vehicle fluid leaks, salt, and sediment, to local streams and rivers. This process includes updating the Storm Water Management Plan and the Pollution Prevention Plans, developing standard operating procedures, mapping storm sewer infrastructure, training staff, and conducting annual regulatory reports. Weston assisted MDT in collecting new ArcGIS mapping data and developed Survey 123 forms and ArcCollector data to obtain information about storm drain inlets, open channels, subsurface conduits/pipes, dry wells, and other stormwater conveyances. Weston also conducted on-site reviews of MDT-maintenance facilities to evaluate pollutant sources, storm water discharge patterns, and Best Management Practices. By performing these tasks, Weston is helping to protect Montana’s waterways to ensure locals and tourists can continue to safely fish and enjoy recreational activities in Montana’s great outdoors.