Municipal Separate Storm Sewer System (MS4) permit requirements
were implemented in two phases: Phase I for large
and medium MS4s and Phase II for regulated small
MS4s.
Phase I MS4 Requirements
If you operate an MS4 which serves or is located in an
incorporated place or county with a population of 100,000 or
greater (based on the 1990 U.S. Census), then you operate a
regulated Phase I MS4 and you must
apply for a renewal permit*.
*Please note that all Phase I MS4s are already permitted and
there are no new Phase I designations.
Phase II MS4 Requirements
If you operate a small MS4
-
located in an urbanized area
(UA), as defined by the Bureau of the Census
-
or located outside of a UA and are brought into the program on a
case-by-case basis by the Texas Commission on Environmental Quality
(TCEQ),
Then you operate a regulated small MS4 and must obtain
authorization.
To determine if you are located in a UA you can visit the
Environmental Protection Agency's (EPA's) Urbanized Area Map Results
for Texas web
page and find maps to urbanized areas in a city near you.
Contact us if
you have any questions about this general permit.
