WHAT IS AN URBANIZED AREA AND HOW DOES IT RELATE TO STORM WATER REGULATIONS?
With the implementation of the Phase II storm water regulations, small
municipal separate storm sewer systems (MS4s) that serve urbanized areas,
among other criteria, will have to obtain NPDES permit coverage by March 10,
The Bureau of the Census defines the criteria that constitute an urbanized
area. Published in a Federal Register document (55 FR 42592) on October 22,
1990, the Bureau of the Census¹ general definition is of an urbanized area
is a land area comprising one or more places < central place(s) < and the
adjacent densely settled surrounding area < urban fringe < that together
have a residential population of at least 50,000 and an overall population
density of at least 1,000 people per square mile.