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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 l​apse in coverage.  

 ​Public Notice Regarding Public Comments on Limited Remand of 20-SW ​​​

The Department's Final Determination for the 20-SW was challenged in the Circuit Court for Baltimore County.  In accordance with an order from the Circuit Court, the Department has agreed to a limited remand to accept comments on three specific sections of the 20-SW permit.   The 20-SW remains in effect pending a final decision by the Department on these sections.  The remainder of the 20-SW is final and not open for public comment.  See the fu​ll text of ​the public notice, below, for specific details regarding this remand and how to submit comments.  Note that the original notice publ​ished by the Department identified November 14, 2023​ as the deadline for submission of comments.  This date has been corrected, as stated in the notice linked below.  The deadline for comments on this matter is Saturday, November 25, ​2023 at 5:00 p.m. 


Permit Training​​​​

The Department offers free training opportunities for several of its general permits.  Visit the WPPRP Training Website to sign up for an upcoming training event or to download information from past training events.  

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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