Daniel K. Inouye International Airport Stormwater Program


Plans relating to the HNL Small MS4 NPDES Permit HI S000005 will be posted here for public review and comment for at least 30 calendar days prior to implementation.

  • Currently there are no documents for public comment.

Spills and Illicit Discharge Reporting

Please report any illicit discharges, illegal connections, or other environmental violations to Airport Environmental Health Specialists at (808) 838-8002 and/or Airport Emergency Services at (808) 836-6670.

National Pollutant Discharge Elimination System (NPDES) Permit

Consent Decree

HNL SWMPP (Stormwater Management Program Plan)

The SWMPP has been developed to assist all those parties conducting operations on HNL with meeting the requirements detailed in the NPDES Permit.

The HNL SWMPP is available at the following location:

State Department of Transportation
Airports Division
400 Rodgers Boulevard, Suite 700
Honolulu, Hawaii 96819-1880
ATTN: HNL Environmental Program (AIR-EE)

Airport Maps

Bodies of Water (PDF 477.3Kb)
HNL Municipal Separate Storm Sewer System (MS4) Map. (Revised March 2019) (16 MB) ** Please note that the map may be periodically updated.

Extended Education and Outreach Program

Fact Sheet: Illicit Discharges & Illegal Connections (523KB)
Landscaping Materials Guide (652 KB)
Stormwater Activity Book (920MB)
Hazardous Waste Materials Guide (1 MB)
HNL Maintenance Baseyard Fact Sheet (4 MB)
Best Management Practices for Tenant Operations at State of Hawaii Airports (869 KB)
Airports Stormwater Pollution Depiction (37KB)
PBMP Inspection & Maintenance Fact Sheet (706KB)

Useful Links

Department of Health – Clean Water Branch
United States Environmental Protection Agency

City & County of Honolulu Department of Environmental Services
State of Hawaii Department of Transportation Stormwater Management

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