Honolulu County regulates stormwater under ROH Chapter 43, Article 11 and Chapter 14, requiring connections to the city's separate storm sewer system and prohibiting non-stormwater discharges across all Oahu watersheds.
The City and County of Honolulu operates a municipal separate storm sewer system (MS4) under a state NPDES permit. ROH Chapter 43, Article 11 governs drainage, flood, and pollution control, with Sec. 43-11.12 addressing connections to the city storm sewer and Sec. 43-11.22 prohibiting discharge of effluent other than stormwater. Administrative Rules Relating to Water Quality adopted under ROH Chapter 14 implement more detailed standards, including construction site BMPs and post-construction controls. These rules protect all Oahu watersheds, from Ala Wai Canal to windward streams.
Illicit discharges or failed stormwater controls can result in Department of Facility Maintenance notices, required corrective action, and administrative penalties typically up to $10,000 per day under state NPDES-backed authority.
Honolulu County, HI
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Honolulu County, HI
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Honolulu County, HI
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Honolulu County, HI
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Honolulu County, HI
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Honolulu County, HI
Honolulu's Land Use Ordinance Section 21-4.60 limits fence, wall, and hedge heights across zoning districts and imposes additional setback or landscape scree...
See how Honolulu County's stormwater management rules stack up against other locations.
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