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Storm Water Manual

We are in the process of revising the manual. Information in the "New Chapters" supersedes that in the equivalent old chapters.

  • ISWMM New Chapter 1 Section 5 - Stormwater Management Plan
  • ISWMM New Chapter 3 Section 1 - Unified Sizing Criteria
  • ISWMM New Chapter 8 - Permeable Pavement Systems
  • ISWMM New Chapter 9 - Detention Practices