National_Map_of_Regulated_MS4s_2009.png
No higher resolution available.
Summary
| Description |
English:
"National Map of Regulated MS4s", showing the location of Municipal Separate Storm Sewer Systems (MS4) in the United States. The MS4s are regulated by discharge permits under the
National Pollutant Discharge Elimination System
(NPDES). Phase I Ms4s are medium and large cities or certain counties with populations of 100,000 or more. Phase II MS4s are smaller systems in U.S. Census Bureau defined urbanized areas, as well as MS4s designated by the permitting authority (EPA or state agency).
|
| Date | |
| Source | U.S. Environmental Protection Agency, "Stormwater Discharges from Municipal Sources." |
| Author | U.S. Environmental Protection Agency, Washington, D.C. |
Licensing
|
This image (or other media) is a work of an
Environmental Protection Agency
employee, taken or made as part of that person's official duties. As
works
of the
U.S. federal government
, all EPA images are in the
public domain
.
|
|