This page contains information about UIC stormwater drainage wells. Rule 15A NCA 02C.227 allows for the use of these wells in North Carolina.
More information about stormwater management is available from the Division of Energy, Mineral and Land Resources (DEMLR) Stormwater Permitting Program. See Memo describing stormwater injection regulations.
EPA Stormwater Injection Wells Information
Stormwater injection is the emplacement of stormwater into the subsurface via a well, subsurface distribution system, or sinkhole and other natural depressions. Certain stormwater infiltration systems meet the regulatory definition of an injection well. Injection wells are regulated by the Underground Injection Control (UIC) Program.
Injection well regulations adopted in 1997 prohibit stormwater injection. However, revised regulations effective May 1, 2012, allow stormwater injection under certain conditions. This revision was made to eliminate a regulatory conflict between the 1997 injection well rules prohibiting stormwater injection and stormwater BMPs that promote stormwater infiltration as a means of protecting surface water quality and enhancing groundwater recharge.
Many of the same concerns about stormwater runoff entering surface water bodies also apply to groundwater, which provides approximately half North Carolina's water supply needs. Stormwater runoff may contain automotive fluids, metals, nutrients, salts, fertilizers, pesticides, and microorganisms. Proper treatment and infiltration of stormwater is an important part of protecting North Carolina's groundwater resources.
Stormwater injection is only allowed to occur via rooftop runoff infiltration systems or infiltration systems that are designed and operated in accordance with federal or state stormwater regulations. Untreated stormwater shall not be emplaced directly into any aquifer and the operation of any stormwater injection well cannot result in the violation of any groundwater quality standard specified in 15A NCAC 02L.
Stormwater infiltration systems subject to State and local government stormwater regulations do not need a separate permit from the UIC Program. Rather, a notification form shall be submitted to the UIC Program in order to comply with federal injection well inventory reporting requirements.
Which types of stormwater BMPs need to be reported as injection wells?
Stormwater infiltration systems that use subsurface distribution systems, drain tiles, perforated or open-bottom pipes, or similar mechanisms designed emplace stormwater into the subsurface. Many different system designs are possible. The following table lists various types of stormwater BMPs and indicates which ones need to be reported to the UIC Program.