PHASE I VRS PHASE II MUNICIPAL SEPARATE STORM SEWER SYSTEMS (MS4)?
The Phase I MS4 Permit regulates systems owned or operated by incorporated cities or counties with a population of over 100,000 or more per the 1990 US Census.
Phase II MS4 Permit regulates entities located in an urbanized area (UA), as defined by the Bureau of the Census (note that MS4s may be regulated based on the 2000 or the 2010 Census UAs) or located outside an Urban Area but serves a jurisdiction with 10,000 or more people with an average density of 1,000 or more people per square mile.
The City of Celina currently falls under the Phase II MS4 Permit regulation.