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(TNW) or wetlands adjacent to TNWs. Wetlands adjacent to non-TNWs are subject to
jurisdiction of the CWA if: (1) the water body is a relatively permanent water (RPW), i.e.
flows year-round or at least 3 months of the year, or is a wetland that directly abuts an
RPW; or (2) a water body including adjacent wetlands that have a significant nexus based
on the biological, physical, or chemical integrity with TNWs.
6.1.3.3 Sanitary Sewer Overflows
The USEPA prohibits discharges to waters of the United States from municipal separate
storm sewer systems (MS4s), unless authorized by an NPDES permit. In April 2000, the
USEPA released the
Compliance and Enforcement Strategy Addressing Combined Sewer
Overflows and Sanitary Sewer Overflows
(USEPA, 2000). In summary, each USEPA region is
responsible for developing an enforcement response plan, which includes an inventory of
sanitary sewer overflow (SSO) violations. State regulations (15A NCAC 2B.05.06) require
municipalities and other wastewater treatment operators to report wastewater spills from
discharges of raw sewage from broken sewer lines and malfunctioning pump stations
within 24 hours. NCDWR adopted policies, which include strict fines and other enforcement
programs, to protect surface water quality from wastewater spills.
For public health, environmental, and regulatory reasons, eliminating SSOs is a high
priority for the Town of Cary including the portion of its service area in the Town of
Morrisville, as it is for the State of North Carolina. The Town of Cary seeks not only to
comply with the minimum requirements regulating its operations, but also to eliminate
SSOs in the Town system to the maximum extent feasible.
The North Carolina Clean Water Bill of 1999 provides for the development of permits for
collection systems that include requirements for inspections, sewer maintenance, and other
operational items. The Town’s infrastructure is operated by the Town of Cary.
6.1.3.4 NPDES Stormwater Regulations
NPDES stormwater discharges are controlled by the Federal NPDES regulations and
enforced by NCDEMLR. The program regulates all major discharges of stormwater to
surface waters. NPDES permits are designed to require the development and
implementation of stormwater management measures. These measures reduce or eliminate
pollutants in stormwater runoff from certain municipal storm sewer systems and industrial
activities.
The NPDES stormwater permitting system is being implemented in two phases. Phase I was
implemented in 1991 and applied to 6 MS4s in North Carolina with populations greater
than 100,000 people at that time (and thus, did not include the Town). USEPA’s Phase II
rules were finalized on October 29, 1999, and published in the Federal Register on December
8, 1999. The Town was required to develop and implement a stormwater management
program.
In 2006, the North Carolina General Assembly enacted Session Law 2006-246 to provide for
the implementation of Phase II stormwater management requirements. Session Law 2006-
246 is related to, but is not a part of, the NPDES stormwater program and recognizes that
urban development can impact surface waters regardless of whether the NPDES stormwater
requirements apply. The Session Law established post-construction stormwater
management requirements for development activities in areas outside of municipalities that