Drinking Water Quality Reports

The United States Environmental Protection Agency (EPA) requires that all drinking water suppliers provide a water quality report to their customers on an annual basis. This is the MUD’s Annual Report Card and is intended to provide you with important information about your drinking water and the efforts made by the Fern Bluff MUD to provide safe drinking water. 

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Este reporte incluye información importante sobre el agua potable. Para obtener una copia de esta información traducida al español, favor de llamar por teléfono a (512) 238-0606.

All Drinking Water May Contain Contaminants

When drinking water meets federal standards, there may not be any health-based benefits to purchasing bottled water or home treatment devices. Drinking water, including bottled water, may reasonably be expected to contain at least small amounts of some contaminants. Contaminants that may be present in source water include:
‐ Microbial contaminants, such as viruses and bacteria, which may come from sewage treatment plants, 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.
‐ 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 occurring or be the result of oil and gas production and mining activities. 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 EPA’s Safe Drinking Water Hotline at (800) 426‐4791.

Special Notice Required Language for ALL Public Water Supplies

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; those 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 your physician or health care provider. Additional guidelines on appropriate means to lessen the risk of infection by Cryptosporidium are available from the Safe Drinking Water Hotline at (800) 426-4791.

Secondary Constituents

Many constituents, such as calcium, sodium, or iron, which are often found in drinking water, can cause taste, odor, and color issues. The taste and odor are called secondary constituents and are regulated by the State of Texas, not EPA. These constituents are not causes for health concerns. Therefore, secondary constituents are not required to be reported in this document, but they may greatly affect the appearance and taste of your water.

Where Your Water Comes From

Fern Bluff MUD purchases its drinking water from the City of Round Rock. The Texas Commission on Environmental Quality (TCEQ) completed an assessment of the city’s source water and results indicate that some of the sources are susceptible to certain contaminants. The sampling requirements for the water system are based on this susceptibility and previous sample data. Any detection of these contaminants will be found in this report. For more information on source water assessments and protection efforts in our water system, please contact Fern Bluff MUD at (512) 238-0606. In addition, source water assessment information is available on Texas Drinking Water Watch at http://dww2.tceq.texas.gov/DWW/.


The public is welcome to attend the Fern Bluff MUD Board of Directors meetings held the second Tuesday of each month at 7320 Wyoming Springs Dr. in Round Rock. For specific questions related to this report, please call (512) 238-0606 or email waterquality@fernbluffmud.org.

Our Drinking Water Meets or Exceeds All Federal (EPA) Drinking Water Requirements

The Fern Bluff MUD had no reporting, monitoring, maximum contaminant level exceedance or notification violations in 2022. This report is a summary of the quality of the water provided to our customers. The analysis was made using EPA required testing and is presented in the following pages.


Many consumers have or consider installing water softeners. The water hardness in our water system ranges from 160-208 mg/L or approximately 9-12 grains per gallon. While this level of hardness may cause minor aesthetic problems such as water spots and dry skin, it does not cause damage to your plumbing. The city routinely performs laboratory tests to measure the stability of the drinking water. The stability refers to whether the water is aggressive or depositional. Test results indicate that the drinking water, as delivered to your home, is stable.

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

Action Level: – The concentration of a contaminant which, if exceeded, triggers treatment or other requirements which a water system must follow.

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.

Avg:   – Regulatory compliance with some MCLs are based on running annual average of monthly samples.

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 or 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 or 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.

Maximum residual disinfectant level or 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 disinfectant level goal or 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.

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

mrem: – millirems per year (a measure of radiation absorbed by the body)

NTU – nephelometric turbidity units (a measure of turbidity)

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

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

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

ppq – parts per quadrillion, or picograms per liter (pg/L)

ppt – parts per trillion, or nanograms per liter (ng/L)

Treatment Technique or TT: – A required process intended to reduce the level of a contaminant in drinking water.


Fern Bluff MUD’s Backflow Prevention Program is in place to help prevent potentially dangerous backflow into the water system by way of swimming pools or irrigation systems. We use Backflow Solutions Inc. (BSI) as our managing company for notification and collection of our backflow reports. Any Property with or considering installing a pool with an autofill valve or an irrigation system is required to have a backflow prevention device installed, tested upon installation, and tested every 7 years thereafter. Local testers can be found on BSI website at www.bsionlinetracking.com. The District will inventory existing pools and irrigation systems and will notify customers of appropriate action needed via our contractor, BSI Online.

 A Note about Storm Water and Pollution Prevention

The Fern Bluff MUD works to prevent pollution of our lakes, creeks, rivers, streams and aquifers. Storm water pollution can lead to contamination of these vital water sources and increase the cost of treating drinking water as well as adversely impacting the environment. Storm water pollution occurs when rainfall picks up and carries pollutants into local waterways and aquifers. How can you help? Never sweep leaves or grass clippings into streets or storm drains. Take used oil and home chemicals to a recycling center or to a household hazardous waste collection event. Follow directions on pesticides and fertilizers and avoid application when rain is forecast. If you have pets, pick up their waste and dispose of it properly to keep bacteria and parasites out of our creeks. Remember, our storm water drains to Brushy Creek.

Household Hazardous Waste Disposal (HHW) The Fern Bluff MUD has joined with the City of Round Rock to make it easier and much more convenient for our residents to dispose ofhousehold hazardous waste.   MUD residents are now allowed to dispose of their HHW at the city’s Deepwood drop-off facility on limited days. For more information on how to get your voucher, please visit our website: https://fernbluffmud.org/household-hazardous-waste-disposal-program.