Surface Water Standards

Surface Water Quality Standards

What Are Water Quality Standards?

Water quality standards are state regulations or rules that serve to protect the lakes, rivers, streams, and other surface waters of the state from the deleterious effects of pollution. Surface waters are protected based on their designated "best uses" as defined in the surface water classifications established in Title 15A of the North Carolina Administrative Code (NCAC) subchapter 02B. For more information on surface water classifications, please see the Surface Water Classifications webpage.

The current water quality standards for surface waters can be viewed here in rules 15A NCAC 02B .0100 through .0300 (effective date: September 1, 2022).

Water quality standards are implemented through the issuing of permit limits to facilities with National Pollutant Discharge Elimination (NPDES) permits, the establishment of water quality benchmarks for the Stormwater Permitting Program, and the development of Total Maximum Daily Loads (TMDLs). Water quality standards are also used to determine the "use status" of surface waters. Waters that are meeting their prescribed water quality standards and that have good biological communities are considered to be supporting all of their uses. Waters that are not meeting these requirements may be considered "impaired" and may require further analysis and, possibly, a management strategy.

More information on biological communities can be found on the Biological Assessment Branch website. Information on impaired waters can be found on the 303d Impaired Waters website.

North Carolina's Legal Obligations & Responsibilities

States are required, under the Federal Water Pollution Control Act (Clean Water Act), to review their water quality standards and classifications every three years and to make any modifications necessary to protect the waters of the state. During this process, known as a Triennial Review, DEQ staff review current EPA guidelines, scientific data, and public comments and make recommendations for any changes of the water quality standards to the North Carolina Environmental Management Commission (EMC). Following a stakeholder comment period, public hearings, and fiscal analysis, and upon approval by the EMC, the Triennial Review package goes to the North Carolina Rules Review Commission (RRC) for final approval and adoption into state rule.

Water Quality Standards Tables & Variances

The following water quality standard tables are resources to be used as a reference for looking up water quality standards or criteria for the waters of the state. They do not substitute for any written regulations, nor are they regulations themselves. To use these tables: First, locate the pollutant of interest in the left column. Next, read across the table to the right to find the water quality standard or criteria related to the designated use associated with the water body of interest. If a water body has multiple designated uses, the most protective standard or criteria will be applied.

Current Rulemaking

Tab/Accordion Items

The North Carolina Department of Environmental Quality (NCDEQ) has begun work on the 2023-2025 Surface Water Quality Standards Triennial Review. NCDEQ staff have reviewed the current surface water standards rules, existing US Environmental Protection Agency (EPA) National Recommended Water Quality Criteria (NRWQC), past triennial review public comments, and other scientific information.  Based on this information, the following list of topics are proposed for inclusion in this triennial review: 

  1. Update existing fish consumption standards for 12 chemicals in 15A NCAC 02B .0208 to align with the EPA NRWQC that were revised in 2015. 

  2. Update existing water supply standards for 14 chemicals in 15A NCAC 02B .0212, .0214, .0215, .0216, and .0218 (Class WS I-V) to align with the EPA NRWQC that were revised in 2015.  

  3. Update the human health exposure factors for Body Weight, Water Consumption Rate and Fish Consumption Rate in 15A NCAC 02B .0208 to align with the EPA NRWQC exposure factors that were revised in 2015. 

  4. Update the primary recreation (Class B) bacterial indicator organism in 15A NCAC 02B .0219 from fecal coliform bacteria to Escherichia coli (E. coli) to align with the EPA Recreational Water Quality Criteria that were revised in 2012. 

  5. Update language in 15A NCAC 02B .0226 for water quality standard variances to reference EPA regulations at 40 CFR § 131.14 as requested by EPA. 

  6. Make technical corrections as needed to correct identified typos and other errors in these rules. 

 

TR Presentation - WQC (July 2023)

Historical Triennial Review Information

Tab/Accordion Items

Public Notice - Includes information regarding the proposed rulemaking actions for the 2020-2022 Surface Water Standards Triennial Review and information for the public hearing associated with this rulemaking

Public comments:

Proposed rule amendments:

Summary of triennial review proposed amendments:

  • Triennial review summary presentation (EMC approved March 11, 2021)
  • Cadmium
  • Cyanide
    • Update the current Class C aquatic life standard for Cyanide to include the option to analyze Cyanide as either free or total Cyanide. This will align the current Class C standard for total Cyanide with the EPA National Recommended Water Quality Criteria which recommends analysis as free Cyanide. 
    • References:
  • Definitions
    • Add new definitions for the terms "Lentic" and "Lotic" (associated with the proposed selenium standard)
    • Provide clarification for the existing "Industrial discharge" definition
  • Eastern Band of Cherokee Indians
    • Amend language in 15A NCAC 02B .0301 to address unnamed tributaries entering Eastern Band of Cherokee Indian boundaries
  • Recreational criteria (E. coli)
    • Establish a site-specific E. coli Primary Recreation (Class B) surface water standard for the 19 counties that comprise the Asheville region of North Carolina. E. coli would replace fecal coliform as the pathogenic indicator in these Class B waters.
    • References:
  • Selenium
  • 1,4-Dioxane
  • Technical corrections
    • Include technical corrections to existing language in the following rules:
      • 15A NCAC 02B .0215 
      • 15A NCAC 02B .0216
      • 15A NCAC 02B .0311

Hearing Officer's Report and Supplemental Information

EPA Documentation

More Information:

For additional information and questions please contact: Christopher Ventaloro, Water Quality Standards Coordinator, at christopher.ventaloro@ncdenr.gov

High Rock Lake EPA Approval Letter

High Rock Lake EPA Decision Document

DWR Overview of HRL Chlorophyll a Site-Specific Standard Proposal - Version 2

High Rock Lake Hearing Officer's Report

HRL Presentation - EMC July 2022

Public Notice - Includes information regarding the proposed rulemaking actions for the site-specific chlorophyll-a standard for High Rock Lake and information for the public hearing associated with this rulemaking.
 
Proposed rule amendments:

Summary of the proposed rule amendments:

  • A site-specific chlorophyll-a standard for High Rock Lake is proposed to be added to the 15A NCAC 02B .0211 rule.
  • The proposed site-specific standard rule language can be viewed in the 15A NCAC 02B .0211 rule linked above under "Proposed rule amendments".
  • The proposed site-specific standard was developed as part of the North Carolina Nutrient Criteria Development Plan and establishes a chlorophyll-a standard that is designed to address nutrient-related impacts to the designated uses of High Rock Lake. The proposed standard considers magnitude, duration, frequency, spatial, and temporal (seasonal) components and also provides a site-specific narrative standard. For more information on the development of the site-specific standards see the NC DWR Overview of High Rock Lake (HRL) Chlorophyll a Site-Specific Standard Proposal document and the NCDP Science Advisory Council A Chlorophyll a Criterion for High Rock Lake (May 2020), both linked below.
  • The existing 15A NCAC 02B .0211 chlorophyll-a surface water standard will continue to apply in all other surface waters.
Public Comments 

These comments are an Adobe PDF Portfolio, not a standard PDF. It is recommended that you use Adobe Acrobat software to view it, as third party PDF viewers may not be able to correctly display it.

Recording of October 28, 2021 Public Hearing

Additional information:

For additional information and questions please contact: Christopher Ventaloro, Water Quality Standards Coordinator, at christopher.ventaloro@ncdenr.gov