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Phase I MS4 Permits

The Phase I MS4 Permits issued throughout the State are presented below by Regional Water Board.

Regional Water Boards

Region 1 – North Coast Water Board

Region 2 – San Francisco Bay Water Board

Region 3 – Central Coast Water Board

Region 4 – Los Angeles Water Board

Region 5 – Central Valley Water Board

Region 6 – Lahontan Water Board

Region 7 – Colorado River Water Board

Region 8 – Santa Ana Water Board

Region 9 – San Diego Water Board


(Updated 4/3/24)

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