CCR 2015 Report(Calendar 2014 Test Results)

2015 Annual Drinking Water Quality Report
Calendar 2014 Test Results

(Consumer Confidence Report)

South Tawakoni Water Supply Corp.
P.O. Box 485
Wills Point, Texas 75169
May 22, 2015

2015 Drinking Water Quality Report
(Calendar 2014 Test Results)
Consumer Confidence Report (CCR)

This information has been prepared to provide our customers with information on the quality of their drinking water. (Jan. – Dec. 2014)

Our Drinking Water Meets or Exceeds All Federal (EPA) Drinking Water Requirements
This report is a summary of the quality of water we provide our customers. The analysis was made by using the data from the most recent U.S. Environmental Protection Agency (EPA) required tests and is presented in the following pages. We hope this information helps you become more knowledgeable about what’s in your drinking water.

En Español

Este informe incluye información importante sobre el agua potable. Si tiene preguntas o comentarios sobre este informe en Español, favor de llamar al tel. (903-873-2509) para hablar con una persona bilingue en Español.

2015 Drinking Water Quality Report Contact Person:
Richard Phillips, General Manager
If you have any question about this report please call our office at 903-873-2509.

Sources of Water:
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 storm water 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 storm water 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 storm water runoff, and septic systems
  • Radioactive contaminants, which can be naturally-occuring or be the result of oil and gas production and mining activities.

Where do we get our drinking water?
The raw water source for STWSC is surface water from Lake Tawakoni.
The source water name is 3-TAWAKONI DAM.

The following tables contain scientific terms and measures, some of which may require explanation.

Regulatory compliance with some MCLs are based on running annual average of monthly samples

Maximum Contaminant Level (MCL)
The highest permissible level of a contaminant 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 health risk. MCLGs allow for a margin of safety.

Maximum Residual Disinfectant Level (MRDL)
The highest level of disinfectant allowed in drinking water. There is convincing evidence that addition of a disinfectant is necessary for control of microbial contaminants.

Maximum Residual Disinfectant 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 contamination.

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 much provide the same protection for public health.

Contaminants may be found in drinking water that may cause taste, color, or odor problems. These types of problems are not necessarily causes for health concerns. For more information on taste, odor, or color of drinking water, please contact the system’s business office.

You may be more vulnerable than the general population to certain microbial contaminants, such as Cryptosporidium, in drinking water. Infants, some elderly, or immunocompromised persons such as those undergoing chemotherapy for cancer; persons who have undergone organ transplants; those who are undergoing treatment with steroids; and people with HIV/AIDS or other immune system disorders, can be particularly at risk from infections. You should seek advice about drinking water from our physician or health care providers. Additional guidelines on appropriate means to lessen the risk of infection by Cryptosporidium 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. We are responsible for providing high quality drinking water, but we 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

Information about Source Water Assessments:
A Source Water Susceptibility Assessment for your drinking water sources is currently being updated by the Texas Commission on Environmental Quality. This information describes the susceptibility and types of constituents that may come into contact with your drinking water source based on human activities and natural conditions. The information contained in the assessment allows us to focus source water protection strategies.

For information about your sources of water, please refer to the Source Water Assessment Viewer available at the following URL:

Further details about sources and source water assessments are available in Drinking Watch at the following URL:

STWSC Water Loss Report
In the water loss audit submitted to the Texas Water Development Board for the time period of Jan. – Dec. 2014, our system lost an estimated 11.11% of total gallons of water pumped.

MFL:   million fibers per liter (a measure of asbestos)

na:   not applicable.

NTU:   nephelometric turbidity units (a measure of turbidity)

pCi/L:   picocuries per liter (a measure of radioactivity)

ppm:   milligrams per liter or parts per million – or one ounce in 7,350 gallons of water.

ppb:   micrograms per liter or parts per billion – or one ounce in 7,350,000 gallons of water

ppt:   parts per trillon, or nanograms per liter (ng/L)

ppq:   parts per quadrillon, or picograms per liter (pg/L)

2014 Regulated Contaminants Detected

Lead and Copper

Action Level Goal (ALG): The level of a contaminant in drinking water below which there is no known or expected risk to health. ALGs allow for a margin of safety.
Action Level: The concentration of a contaminant which, if exceeded, triggers treatment or other requirements which a water system must follow.
Lead and Copper Date Sampled MCLG Action Level (AL) 90th Percentile #Sites Over AL Units Violation Likely Source of Contamination
Copper 2014 1.3 1.3 0.49 0 ppm N Erosion of natural deposits; Leaching from wood preservatives; Corrosions and household plumbing systems.
Lead 2014 0 15 2.9 0 ppb N Corrosion of household plumbing systems; Erosion of natural deposits.

Regulated Contaminants

Disinfectants and Disinfection By-Products Collection Date Highest Level Detected Range of Levels Detected MCLG MCL Units Violation Likely Source of Contamination
Haloacetic Acids (HAA5)* 2014 22 17.4-23.6 No goal for the total 60 ppb N By-product of drinking water chlorination.
Total Trihalomethanes (TThm)* 2014 23 14-31.9 No goal for the total 80 ppb N By-product of drinking water chlorination

Disinfection Data

Year Disinfection Data Average Level Minimum Level Maximum Level MRDL MRDLG Unit of Measure Source of Chemical
2014 Chloramine 3.495 1.4 4.9 4.0 <4.0 ppm Chloramine Disinfectant used to control microbes.

Inorganic Contaminants Collection Date Highest Level Detected Range of Level Detected MCLG MCL Units Violation Likely Source of Contamination
Arsenic 2014 1 1.1-1.1 0 10 ppb N Erosion of natural deposits; Runoff from orchards; Runoff from glass and electronics production wastes.
Barium 2014 0.082 0.082-0.082 2 2 ppm N Discharge of drilling wastes; Discharge from metal refineries; Erosion of natural deposits.
Chromium 2014 3.1 3.1-3.1 100 100 ppb N Discharge from steel and pulp mills; Erosion of natural deposits.
Cyanide 2014 36.2 36.2-36.2 200 200 ppm N Discharge of drilling wastes; Discharge from metal refineries; Erosion of natural deposits.
Fluoride 2014 0.2 0.224-0.224 4 4.0 ppm N Erosion of natural deposits; Water additive which promotes strong teeth; Discharge from fertilizer and aluminum factories.
Nitrate (measured as Nitrogen) 2014 1 0.566-0.566 10 10 ppm N Runoff from fertilizer use; Leaching from septic tanks, sewage; Erosion of natural deposits.
Nitrate Advisory – Nitrate in drinking water at levels above 10 ppm is a health risk for infants of less than six months of age. High nitrate levels in drinking water can cause blue baby syndrome. Nitrate levels may rise quickly for short periods of time because of rainfall or agricultural activity. If you are caring for an infant you should ask advice from your health care provider.


Synthetic organic Contaminants including pesticides and herbicides Collection Date Highest Level Detected Range of Levels Detected MCLG MCL Units Violation Likely Source of Contamination
Atrazine 2014 0.26 0.26-0.26 3 3 ppb N Runoff from herbicide used on row crops.
DI (2-ethylhexyl) phthalate 2014 2 1.5-1.5 0 6 ppb N Discharge from rubber and chemical factories.


Turbidity Limit (Treatment Technique) Level Detected Violation Likely Source of Contamination
Highest single measurement 1 NTU 0.29 NTU N Soil runoff.
Lowest monthly % meeting limit 0.3 NTU 100% N Soil runoff.

TX 2340019

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