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General Discharge Permit

​General Permit For Discharges from Stormwater Associated with Industrial Activities
Maryland General Permit No. 20-SW

 ​NOTICE - Permit Issued (effective February 1, 2023) ​​​

The Department has issued the final renewal permit for the General Permit for Discharges ​from Stormwater Associated with Industrial Activities, effective February 1, 2023.  Existing permittees must submit a Notice of Intent (NOI), fee, and SWPPP no later than July 31, 2023 to prevent a lapse in coverage.  

​​​ Upcoming Training Opportunities ​​​​

The Department is offering free training opportunities to any party interested in learning more about the 20-SW General Permit.  If you own or operate a facility​ which was registered under the previous 12-SW permit or which falls into an industrial sector identified in Appendix A of the permit as requiring coverage for ​industrial stormwater, you are stron​gly encouraged to attend.  The dates for currently-scheduled events are presented below.  Please click on t​he respective link to sign up to attend the training​.  

20-SW Permit Information​



Guidance Documents

Supplemental Information​

The Public Notice of Final Determination contains a list of changes which have been made in response to comments received following publication of a draft tentative determination.  A detailed response to each substantive comment is provided in the Response to Public Comments document.  Changes which were already made as part of the tentative determination are identified and rationalized in the 20-SW Fact Sheet.

Contact Info

If you have additional questions or would like more information, please contact the Industrial Stormwater Permits Division at (410) 537-3323.

Previous Permit (12-SW-A)​​

Additional Information and Related L​inks

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