MS4, or similar, may refer to:
* , a possible dwarf planet
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MS4 Modeling Environment, a software package
* ''
Metal Slug 4'', a video game
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Mississippi Highway 4
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Mississippi's 4th congressional district
Mississippi's 4th congressional district covers the southeastern region of the state. It includes all of Mississippi's Gulf Coast, stretching ninety miles between the Alabama border to the east and the Louisiana border to the west, and extends n ...
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Municipal Separate Storm Sewer System (MS4) required pursuant to United States law to regulate
stormwater runoff
Surface runoff (also known as overland flow) is the flow of water occurring on the ground surface when excess rainwater, stormwater, meltwater, or other sources, can no longer sufficiently rapidly infiltrate in the soil. This can occur when the ...
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