2023 Annual Drinking Water Quality Report
Town of Green Level
Water System Number: NC 0201030
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We are pleased to present to you this year’s Annual Drinking Water Quality Report. This report is a snapshot of last year’s water quality. Included are details about your source(s) of water, what it contains, and how it compares to standards set by regulatory agencies. Our constant goal is to provide you with a safe and dependable supply of drinking water. We want you to understand the efforts we make to continually improve the water treatment process and protect our water resources. We are committed to ensuring the quality of your water and to providing you with this information because informed customers are our best allies If you have any questions about this report or concerning your water, please contact Barrett Brown at (336)578-3443. We want our valued customers to be informed about their water utility. If you want to learn more, please attend any of our regularly scheduled meetings. They are held at town hall, 2510 Green Level Church Road Green Level, North Carolina 27217 on the second Thursday of every month at 7:00pm.
What EPA Wants You to Know
Drinking water, including bottled water, may reasonably be expected to contain at least small amounts of some contaminants. The presence of contaminants does not necessarily indicate that water poses a health risk. More information about contaminants and potential health effects can be obtained by calling the Environmental Protection Agency’s Safe Drinking Water Hotline (800-426-4791).
Some people may be more vulnerable to contaminants in drinking water than the general population. Immuno-compromised persons such as persons with cancer undergoing chemotherapy, persons who have undergone organ transplants, people with HIV/AIDS or other immune system disorders, some elderly, and infants can be particularly at risk from infections. These people should seek advice about drinking water from their health care providers. EPA/CDC guidelines on appropriate means to lessen the risk of infection by Cryptosporidium and other microbial contaminants are available from the Safe Drinking Water Hotline (800-426-4791).
If present, elevated levels of lead can cause serious health problems, especially for pregnant women and young children. Lead in drinking water is primarily from materials and components associated with service lines and home plumbing. Green Level is responsible for providing high quality drinking water, but cannot control the variety of materials used in plumbing components. When your water has been sitting for several hours, you can minimize the potential for lead exposure by flushing your tap for 30 seconds to 2 minutes before using water for drinking or cooking. If you are concerned about lead in your water, you may wish to have your water tested. Information on lead in drinking water, testing methods, and steps you can take to minimize exposure is available from the Safe Drinking Water Hotline or at http://www.epa.gov/safewater/lead.
The sources of drinking water (both tap water and bottled water) include rivers, lakes, streams, ponds, reservoirs, springs, and wells. As water travels over the surface of the land or through the ground, it dissolves naturally-occurring minerals and, in some cases, radioactive material, and can pick up substances resulting from the presence of animals or from human activity. Contaminants that may be present in source water include microbial contaminants, such as viruses and bacteria, which may come from sewage treatment plants, septic systems, agricultural livestock operations, and wildlife; inorganic contaminants, such as salts and metals, which can be naturally-occurring or result from urban stormwater runoff, industrial or domestic wastewater discharges, oil and gas production, mining, or farming; pesticides and herbicides, which may come from a variety of sources such as agriculture, urban stormwater runoff, and residential uses; organic chemical contaminants, including synthetic and volatile organic chemicals, which are by-products of industrial processes and petroleum production, and can also come from gas stations, urban stormwater runoff, and septic systems; and radioactive contaminants, which can be naturally-occurring or be the result of oil and gas production and mining activities.
In order to ensure that tap water is safe to drink, EPA prescribes regulations which limit the amount of certain contaminants in water provided by public water systems. FDA regulations establish limits for contaminants in bottled water, which must provide the same protection for public health.
When You Turn on Your Tap, Consider the Source
The water that is used by this system is surface water from Graham-Mebane Lake, treated by and purchased from the City of Graham.
Source Water Assessment Program (SWAP) Results
The North Carolina Department of Environmental Quality (DEQ), Public Water Supply (PWS) Section, Source Water Assessment Program (SWAP) conducted assessments for all drinking water sources across North Carolina. The purpose of the assessments was to determine the susceptibility of each drinking water source (well or surface water intake) to Potential Contaminant Sources (PCSs). The results of the assessment are available in SWAP Assessment Reports that include maps, background information and a relative susceptibility rating of Higher, Moderate or Lower.
The relative susceptibility rating of each source for Graham/ Green Level was determined by combining the contaminant rating (number and location of PCSs within the assessment area) and the inherent vulnerability rating (i.e., characteristics or existing conditions of the well or watershed and its delineated assessment area). The assessment findings are summarized in the table below:
Susceptibility of Sources to Potential Contaminant Sources (PCSs)
| Source Name | Susceptibility Rating | SWAP Report Date |
| Graham/Mebane Lake | Lower | September 2020 |
The complete SWAP Assessment report for Graham/ Green Level may be viewed on the Web at: https://www.ncwater.org/?page=600 Note that because SWAP results and reports are periodically updated by the PWS Section, the results available on this web site may differ from the results that were available at the time this CCR was prepared. If you are unable to access your SWAP report on the web, you may mail a written request for a printed copy to: Source Water Assessment Program – Report Request, 1634 Mail Service Center, Raleigh, NC 27699-1634, or email requests to [email protected]. Please indicate your system name, number, and provide your name, mailing address and phone number. If you have any questions about the SWAP report please contact the Source Water Assessment staff by phone at 919-707-9098.
It is important to understand that a susceptibility rating of “higher” does not imply poor water quality, only the system’s potential to become contaminated by PCSs in the assessment area.
Help Protect Your Source Water
Protection of drinking water is everyone’s responsibility. You can help protect your community’s drinking water source(s) in several ways: (examples: dispose of chemicals properly; take used motor oil to a recycling center, volunteer in your community to participate in group efforts to protect your source, etc.).
Violations that Your Water System Received for the Report Year
During 2023, or during any compliance period that ended in 2023, Green Level received No violations.
Important Drinking Water Definitions:
- Not-Applicable (N/A) – Information not applicable/not required for that particular water system or for that particular rule.
- Non-Detects (ND) – Laboratory analysis indicates that the contaminant is not present at the level of detection set for the particular methodology used.
- Parts per million (ppm) or Milligrams per liter (mg/L) – One part per million corresponds to one minute in two years or a single penny in $10,000.
- Parts per billion (ppb) or Micrograms per liter (ug/L) – One part per billion corresponds to one minute in 2,000 years, or a single penny in $10,000,000.
- Parts per trillion (ppt) or Nanograms per liter (nanograms/L) – One part per trillion corresponds to one minute in 2,000,000 years, or a single penny in $10,000,000,000.
- Parts per quadrillion (ppq) or Picograms per liter (picograms/L) – One part per quadrillion corresponds to one minute in 2,000,000,000 years or one penny in $10,000,000,000,000.
- Picocuries per liter (pCi/L) – Picocuries per liter is a measure of the radioactivity in water.
- Nephelometric Turbidity Unit (NTU) – Nephelometric turbidity unit is a measure of the clarity of water. Turbidity in excess of 5 NTU is just noticeable to the average person.
- Variances and Exceptions – State or EPA permission not to meet an MCL or Treatment Technique under certain conditions.
- Action Level (AL) – The concentration of a contaminant which, if exceeded, triggers treatment or other requirements which a water system must follow.
- Treatment Technique (TT) – A required process intended to reduce the level of a contaminant in drinking water.
- Maximum Residual Disinfection Level (MRDL) – The highest level of a disinfectant allowed in drinking water. There is convincing evidence that addition of a disinfectant is necessary for control of microbial contaminants.
- Maximum Residual Disinfection Level Goal (MRDLG) – The level of a drinking water disinfectant below which there is no known or expected risk to health. MRDLGs do not reflect the benefits of the use of disinfectants to control microbial contaminants.
- Locational Running Annual Average (LRAA) – The average of sample analytical results for samples taken at a particular monitoring location during the previous four calendar quarters under the Stage 2 Disinfectants and Disinfection Byproducts Rule.
- Running Annual Average (RAA) – The average of sample analytical results for samples taken during the previous four calendar quarters.
- Level 1 Assessment – A Level 1 assessment is a study of the water system to identify potential problems and determine (if possible) why total coliform bacteria have been found in our water system.
- Level 2 Assessment – A Level 2 assessment is a very detailed study of the water system to identify potential problems and determine (if possible) why an E. coli MCL violation has occurred and/or why total coliform bacteria have been found in our water system on multiple occasions.
- Maximum Contaminant Level (MCL) – The highest level of a contaminant that is allowed in drinking water. MCLs are set as close to the MCLGs as feasible using the best available treatment technology.
- Maximum Contaminant Level Goal (MCLG) – The level of a contaminant in drinking water below which there is no known or expected risk to health. MCLGs allow for a margin of safety.
Water Quality Data Tables of Detected Contaminants
We routinely monitor for over 150 contaminants in your drinking water according to Federal and State laws. The tables below list all the drinking water contaminants that we detected in the last round of sampling for each particular contaminant group. The presence of contaminants does not necessarily indicate that water poses a health risk. Unless otherwise noted, the data presented in this table is from testing done January 1 through December 31, 2023. The EPA and the State allow us to monitor for certain contaminants less than once per year because the concentrations of these contaminants are not expected to vary significantly from year to year. Some of the data, though representative of the water quality, is more than one year old.
Green Level
REVISED TOTAL COLIFORM RULE:
Microbiological Contaminants in the Distribution System
|
Contaminant (units)
|
MCL Violation
Y/N |
Number of Positive/Present Samples |
MCLG
|
MCL | Likely Source of Contamination |
|
Total Coliform Bacteria (presence or absence) |
N/A | N/A | N/A | TT* | Naturally present in the environment |
| E. coli
(presence or absence)
|
N | 0/ Absent | 0 | Routine and repeat samples are total coliform-positive and either is E. coli-positive or system fails to take repeat samples following E. coli-positive routine sample or system fails to analyze total coliform-positive repeat sample for E. coli
Note: If either an original routine sample and/or its repeat samples(s) are E. coli positive, a Tier 1 violation exists. |
Human and animal fecal waste |
* If a system collecting fewer than 40 samples per month has two or more positive samples in one month, an assessment is required.
Lead and Copper Contaminants
|
Contaminant (units)
|
Sample Date | Your Water
(90th Percentile) |
Number of sites found above the AL | MCLG | AL | Likely Source of Contamination |
| Copper (ppm)
(90th percentile) |
8/30/21 | 0.1 ppm | 0 | 1.3 | AL=1.3 | Corrosion of household plumbing systems; erosion of natural deposits |
| Lead (ppb)
(90th percentile) |
8/30/21 | 0
|
1 | 0 | AL=15 | Corrosion of household plumbing systems; erosion of natural deposits |
Disinfectant Residuals Summary
|
|
MRDL Violation Y/N |
Your
Water (highest RAA) |
Range
Low High |
MRDLG | MRDL | Likely Source of Contamination |
| Chlorine (ppm) |
N |
3 ppm |
3 – 3 ppm |
4 | 4.0 | Water additive used to control microbes |
| Chloramines (ppm) |
N |
2.84 ppm |
2 – 4 ppm |
4 |
4.0 |
Water additive used to control microbes |
Stage 2 Disinfection Byproduct Compliance – Based upon Locational Running Annual Average (LRAA)
|
Disinfection Byproduct |
Year Sampled |
MCL Violation Y/N |
Your Water
(highest LRAA) |
Range
Low High |
MCLG | MCL | Likely Source of Contamination |
|
TTHM (ppb) |
2023 |
N |
N/A |
80 |
Byproduct of drinking water disinfection |
||
| Location B01 | 34 ppb | 19 – 46 ppb | |||||
|
HAA5 (ppb) |
2023 |
N |
N/A |
60 |
Byproduct of drinking water disinfection |
||
| Location B02 | 20 ppb | 8 – 31 ppb | |||||
Results from Graham’s CCR
Turbidity
|
Contaminant (units)
|
Treatment Technique (TT) Violation
Y/N |
Your Water | MCLG |
Treatment Technique (TT) Violation if:
|
Likely Source of Contamination |
| Turbidity (NTU) – Highest single turbidity measurement | N | 0.28 NTU | N/A |
Turbidity > 1 NTU
|
Soil runoff |
| Turbidity (%) – Lowest monthly percentage (%) of samples meeting turbidity limits | N | 100 % | N/A |
Less than 95% of monthly turbidity measurements are < 0.3 NTU
|
Turbidity is a measure of the cloudiness of the water. We monitor it because it is a good indicator of the effectiveness of our filtration system. Turbidity is measured at multiple locations throughout the treatment process. The turbidity above represents Combined Filter Effluent (CFE) turbidity. To meet current turbidity requirements, water must be less 0.3 turbidity units 95 % of the time and never allowed to exceed 1.0 turbidity units in the Combined Filter Effluent (CFE). The 2022 average turbidity for our Combined Filter Effluent (CFE) was 0.09 NTU.
Inorganic Contaminants
|
Contaminant (units)
|
Sample Date | MCL Violation
Y/N |
Your
Water |
Range
Low High |
MCLG | MCL | Likely Source of Contamination |
| Fluoride (ppm) | 7/26/23 | N | 0.54 | N/A | 4 | 4 | Erosion of natural deposits; water additive which promotes strong teeth; discharge from fertilizer and aluminum factories |
The respective concentration of fluoride reported above is the result of a single sample collected on 7/14/22. However, fluoride analysis is conducted every day for process control at the treatment plant. The average fluoride concentration for 2022 was 0.70 mg/L.
There are a number of organics that are of potential concern in drinking water. This group includes Volatile Organic Chemicals (VOCs) which vaporize easily. It also includes Synthetic Organic Chemicals (SOCs) which are manmade and include substances such as pesticides and herbicides. These organic chemicals may come from various sources like agriculture, urban storm runoff, residential uses, industrial processes and petroleum production, gas stations and septic systems.
Volatile Organic Chemical (VOC) Contaminants
City of Graham is required to test for 21 Volatile Organic Chemicals every year. Volatile Organic Chemicals were analyzed in
February of 2023 and there were no detections found for any of the 21 VOCs.
Synthetic Organic Chemical (SOC) Contaminants Including Pesticides and Herbicides
|
Contaminant (units)
|
Sample Date | MCL Violation
Y/N |
Your
Water |
Range
Low High |
MCLG | MCL | Likely Source of Contamination |
| Simazine (ppb) | 2023 | N | 0.18 | N/A | 4 | 4 | Herbicide runoff |
City of Graham is required to test for 26 Pesticides and Synthetic Organic Chemicals in 2 consecutive quarters every three years. Testing was done for these in January, April and May of 2023. There were 25 SOCs that were not detected. City of Graham is required to test for Simazine on an annual basis.
Radiological Contaminants
Radiological contaminants in source water may be naturally occurring or may be the result of oil and gas production and mining activities. Data presented in the table below is from the most recent monitoring event. The City of Graham is required to monitor for radiological contaminants every 9 years.
|
Contaminant (units)
|
Sample Date | MCL Violation
Y/N |
Your
Water (RAA) |
Range
Low High |
MCLG | MCL | Likely Source of Contamination |
| Beta/photon emitters (pCi/L) | 1/25/17 | N | 2.8 | N/A | 0 | 50 * | Decay of natural and man-made deposits |
| Combined radium (pCi/L) | 1/25/17 | N | 1.31 | N/A | 0 | 5 | Erosion of natural deposits |
* Note: The MCL for beta/photon emitters is 4 mrem/year. EPA considers 50 pCi/L to be the level of concern for beta particles.
Total Organic Carbon (TOC)
| Contaminant (units)
|
TT Violation Y/N | Your Water
(lowest RAA) |
Range Monthly Removal Ratio
Low – High |
MCLG | Treatment Technique (TT) violation if: | Likely Source of Contamination |
| Total Organic Carbon (TOC) Removal Ratio (no units)
|
N | 1.40 | 1.30 – 1.58 | N/A | Removal Ration RAA <1.00 and alternative compliance criteria was not met | Naturally present in the environment |
For 2023 the average raw water TOC was 7.28 mg/L and the average combined filter water TOC was 2.35 mg/L. The average TOC removal rate was 67.6% with removal rates ranging from 61% to 72% during 2023.
Disinfectant Residuals Summary
|
|
MRDL Violation Y/N |
Your
Water (highest RAA) |
Range
Low High |
MRDLG | MRDL | Likely Source of Contamination |
| Chlorine (ppm) |
N |
1.17 |
0 – 2.9 |
4 | 4.0 | Water additive used to control microbes |
| Chloramines (ppm) |
N |
2.66 |
0.8 – 3.7 |
4 | 4.0 | Water additive used to control microbes |
Cryptosporidium sp.
Cryptosporidium sp. is a microscopic organism that, when ingested, may cause diarrhea, fever and other gastrointestinal symptoms. The organism occurs naturally in surface waters and comes from animal wastes. Cryptosporidium sp. Is eliminated by an effective treatment combination of coagulation, sedimentation, filtration and disinfection. The Graham-Mebane Lake, your source water, underwent a 2-year sampling program which was completed in 2018. The average concentration of the sampling event was 0.008 oocysts/L.
The PWS Section requires monitoring for other misc. contaminants, some for which the EPA has set national secondary drinking water standards (SMCLs) because they may cause cosmetic effects or aesthetic effects (such as taste, odor, and/or color) in drinking water. The contaminants with SMCLs normally do not have any health effects and normally do not affect the safety of your water.
Other Miscellaneous Water Characteristics Contaminants
The Unregulated Contaminant Monitoring Rule 4 (UCMR4) required water systems to collect and analyze water samples for 20 chemicals and 10 cyanotoxins for which the EPA has not established drinking water standards, therefore are not regulated. The purpose of unregulated contaminant monitoring is to assist EPA in determining the occurrence of unregulated contaminants in drinking water and whether future regulations are warranted. The table below only includes data for the UCMR4 parameters that were detected.
Unregulated Contaminants
|
UCMR4 Parameter
|
Year Tested | Source Water- Graham-Mebane Lake
Average Range |
Graham-Mebane WTP
Average Range |
Distribution System
Average Range |
|||
| Manganese, ug/L | 2020 |
N/A |
N/A |
11.62 | 3.66 – 27.6 | N/A | N/A |
| Bromide, ug/L | 2020 | 21.9 | 21.1 – 22.6 | N/A | N/A | N/A | N/A |
| Total Organic Carbon (TOC)
ug/L |
2020 | 6,870 | 6,090 – 7,870 | N/A | N/A | N/A | N/A |
| Haloacetic Acids- 9, ug/L | 2020 | N/A | N/A | N/A | N/A | 28.63 | 21.82 – 41.02 |
The City of Graham began collecting data for the Unregulated Contaminant Monitoring Rule 5 (UCMR5) in November of 2023. The required sampling for the UCMR5 will continue during 2024 as directed by the EPA. UCMR5 will provide new data that will improve the EPA’s understanding of the frequency that 29 per- and polyfluoroalkyl substances (PFAS) and lithium are found in the nation’s drinking water systems, and at what levels. The monitoring data on PFAS and lithium will help the EPA make determinations about future regulations and other actions to protect public health.
Unregulated Contaminant Monitoring Rule 5 (UCMR5)
|
UCMR5 Parameter
|
Sample Date | Graham-Mebane WTP | Range | Proposed MCL* |
| PFOA, ng/L | 11-13-23 |
7.6 |
N/A | 4
parts per trillion (ng/L) |
| PFOS, ng/L | 11-13-23 | 7.4 | N/A | 4
parts per trillion (ng/L) |
| PFBS, ng/L | 11-13-23 | 10.6 | N/A | 1.0 (unitless)
Hazard Index ** |
| PFHxA, ng/L | 11-13-23 | 3.5 | N/A | Currently N/A |
| PFPeA, ng/L | 11-13-23 | 3.4 | N/A | Currently N/A |
The City of Graham had no detects on the remainder of the 24 per and polyfluoroalkyl substances (PFAS) that were analyzed as part of the UCMR5 on 11-13-23. There was no Lithium detected during the 11-13-23 UCMR5 sampling event.
* EPA has announced the proposed National Drinking Water Regulation (NPDWR) for six per- and polyfluoroalkyl
Substances (PFAS). This proposed NPDWR does not require any actions until the regulation is finalized.
** EPA is proposing a Hazard Index MCL to limit any mixture containing one or more of PFNA, PFHxS, PFBS, and/or
GenX Chemicals. The Hazard Index considers the different toxicities of PFNA, GenX Chemicals, PFHxS, and PFBS. For these PFAS, water systems would use a hazard index calculation to determine if the combined levels of these PFAS in the drinking water at that system pose a potential risk and require action. There were no detects of PFNA, PFHxS or the GenX Chemicals during the City of Graham’s 11-13-23 sampling event.
For more information on PFAS please visit www.cityofgraham.com.