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Guidance on 2025 SWMM Requirements for Projects in the Public Right-of-way

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Source: Guidance on 2025 SWMM Requirements for Projects in the Public Right-of-way ↗ Last modified: Sun, 19 Apr 2026 20:04:13 GMT


Label: Guide


The City's Stormwater Management Manual (SWMM) requires stormwater management if a project:

  • Changes an existing stormwater discharge location; or
  • Adds or redevelops more than 1,000 square feet of impervious area.

 

Please note:

  • Existing or proposed trees in the right-of-way can reduce the amount of area requiring stormwater management.
  • Projects reviewed through a PBOT Minor Improvements Permit will not be reviewed for SWMM conformance.

Find more information about how to determine when a right-of-way project triggers the SWMM ↗.


If stormwater management is required for public improvements, there are three potential options to meet SWMM requirements:

  1. Discharge to existing facilities.
  2. Construct new stormwater facilities.
  3. Pay an Offsite Stormwater Management Fee through Special Circumstances.

Find more information about how to meet SWMM requirements for projects in the right-of-way ↗.


This guidance provides a simplified explanation of SWMM requirements, along with additional diagrams, to assist applicants in understanding how to implement the SWMM. However, always consult the SWMM for complete requirements ↗.

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