What is TriSWM?

The Transportation integrated Stormwater Management (TriSWM) Appendix of the integrated Stormwater Management (iSWM) Criteria Manual for Site Development and Construction is available for use by cities, counties, engineers, private developers, contractors and transportation agencies in the planning and design of stormwater management for streets, roads, and highways.

The purpose of TriSWM is to provide planning and design guidance and a framework for incorporating effective and environmentally sensitive stormwater management practices into the street and roadway project development process, and to encourage a greater uniformity in developing plans for stormwater management systems that meet the following goals: oil on water surface

  • Provide safe driving conditions
  • Minimize downstream flood risk to people and properties
  • Minimize downstream bank and channel erosion
  • Reduce pollutants in stormwater runoff to protect water quality

TriSWM discusses strategies to aid local governments and the private sector to:

  • Design roads and highways with stormwater impacts in mind
  • Address and mitigate the adverse impacts of development on runoff
  • Implement stormwater controls to meet the TriSWM planning and design approach

Download TriSWM Brochure


View the TriSWM Appendix of the iSWM Criteria Manual for Site Development and Construction


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