Sources Of Drinking Water in San Antonio, Texas
Where does San Antonio get its water from? The Edwards Aquifer is a massive underground reservoir, and the source for most of San Antonio's drinking water. SAWS also relies on several non-Edwards Aquifer water sources. The Edwards Aquifer is intensely faulted and fractured carbonate limestone that lies within the Balcones fault zone. The dynamics and size of the this geologic anomaly make it one of the most wondrous aquifers in the nation, through its storage capacity, flow characteristics, water producing capabilities and efficient recharging ability. The Edwards Aquifer and its catchment area in the San Antonio region is about 8,000 square miles and includes all or part of 13 counties in south central Texas.
The recharge and artesian areas of the Edwards Aquifer underlie the six counties south and east of the Balconces fault escarpment. The aquifer underlies approximately 3,600 square miles, is about 180 miles long from west to east and varies from 5 to 30 miles wide. The Edwards Aquifer receives most of its water from the drainage basins located on the Edwards Plateau. The catchment area, about 4,400 square miles, contains the drainage basins of the streams that recharge the Edwards Aquifer.
In the San Antonio region, the Edwards limestone attains a thickness of approximately 450 to 500 feet. Ninety-two water wells supply SAWS customers with an average daily pumpage of 136.50 million gallons per day or 418 acre-feet. From 1934 through 1994 the average recharge to the Edwards Aquifer was 676,600 acre-feet. Is San Antonio's water safe to drink? Does San Antonio put fluoride in the water?
Source: City of San Antonio
Contaminants Found in San Antonio's Water Supply
(Detected above health guidelines)
3rd party independent testing found that this utility exceeds health guidelines for this drinking water contaminant. Bromodichloromethane is one of the total trihalomethanes (TTHMs) that formed when disinfectants, such as chlorine, are used to treat tap water. What are the risks of drinking tap water with Bromodichloromethane? Cancer, Kidney & Liver Damage. Bromodichloromethane and other disinfection byproducts increase the risk of cancer and may cause problems during pregnancy. In recent animal studies, the main effect of eating or drinking large amounts of Bromodichloromethane is injury to the liver and kidneys. Find out more about this contaminant and how to remove it here.
3rd party independent testing found that this utility exceeds health guidelines for this drinking water contaminant. Bromoform (also known as tribromomethane) is a possible contaminant of drinking water that has been chlorinated to kill bacteria and viruses that could cause serious waterborne infectious diseases. Bromoform may form when chlorine reacts with other naturally occurring substances in water, such as decomposing plant material. What are the risks of drinking tap water with bromoform? Liver & Kidney Damage. Some studies in animals indicate that exposure to high doses of bromoform or dibromochloromethane may also lead to liver and kidney injury within a short period of time. Other animal studies suggest that typical bromoform or dibromochloromethane exposures do not pose a high risk of affecting the chance of becoming pregnant or harming an unborn baby. However, studies in animals indicate that long-term intake of either bromoform or dibromochloromethane can cause liver and kidney cancer. Although cancer in humans cannot be definitely attributed to these chemicals, it is an effect of special concern, since many people are exposed to low levels of bromoform and dibromochloromethane in chlorinated drinking water. Find out more about this contaminant and how to remove it here.
3rd party independent testing found that this utility exceeds health guidelines for this drinking water contaminant. Chloroform, is a total trihalomethanes (TTHMs) which is formed when disinfectants are used to treat tap water. Most of the chloroform found in the environment comes from industry. Chloroform enters the environment from chemical companies and paper mills, It is also found in waste water from sewage treatment plants and drinking water to which chlorine has been added. Chlorine is added to most drinking water and many waste waters to destroy bacteria. Small amounts of chloroform are formed as an unwanted product during the process of adding chlorine to water. What are the risks of drinking tap water with chloroform? Cancer, central nervous system (brain), liver, and kidneys. Cancer of the liver and kidneys developed in rats and mice that ate food or drank water that had large amounts of chloroform in it for a long time. We do not know whether liver and kidney cancer would develop in people after long-term exposure to chloroform in drinking water. Based on animal studies, the Department of Health and Human Services has determined that chloroform may reasonably be anticipated to be a carcinogen (a substance that causes cancer). Find out more about this contaminant and how to remove it here.
3rd party independent testing found that this water utility exceeds health guidelines for this drinking water contaminant. The movie Erin Brockovich alerted the public to the great suffering the little town of Hinkley, California experienced due to hexavalent chromium in their drinking water. Today, Hinkley is little more than a ghost town thanks to continued water contamination, health concerns, and plummeting property values. Chromium (hexavalent) is a carcinogen that commonly contaminates American drinking water. Chromium (hexavalent) in drinking water may be due to industrial pollution or natural occurrences in mineral deposits and groundwater. What are the risks of drinking tap water with Chromium (hexavalent)? Cancer. A 2008 study by the National Toxicology Program, part of the National Institutes of Health, found that chromium-6 in drinking water caused cancer in laboratory rats and mice. That study and other research led scientists at the California Office of Environmental Health Hazard Assessment to conclude that chromium-6 can cause cancer in people. Find out more about this contaminant and how to remove it here.
3rd party independent testing found that this utility exceeds health guidelines for this drinking water contaminant. Dibromochloromethane, one of the total trihalomethanes (TTHMs), was used in the past to make other chemicals such as fire extinguisher fluids, spray can propellants, refrigerator fluid, and pesticides. It is now only used on a small scale in laboratories. In the environment, dibromochloromethane is not found as a pure liquid, but instead, it is found either dissolved in water or evaporated into the air as a gas. What are the risks of drinking tap water with Dibromochloromethane? Liver & Kidney Damage. Animal studies indicate that long-term intake of dibromochloromethane can cause liver and kidney cancer. Find out more about this contaminant and how to remove it here.
3rd party independent testing found that this utility exceeds health guidelines for this drinking water contaminant. Dichloroacetic Acid is one of the five haloacetic acids and a member of the chloroacetic acids family. It is an essential chemical compound in medical research, especially in cancer treatment. This type of chloroacetic acid is a trace product of the process of chlorination of drinking water. Dichloroacetic Acid can get into water systems through improper disposal of waste from pharmaceutical factories. What are the risks of drinking tap water with Dichloroacetic acid? Cancer, Reproductive Issues, Child Development. Dichloroacetic Acid in drinking water may cause health problems during pregnancy, liver and kidney damage, reproductive difficulties, eyes and nerve problems, and an increased risk of getting cancer. Dichloroacetic Acid is common in municipal water since it is a trace product of the chlorination of drinking water. Find out more about this contaminant and how to remove it here.
3rd party independent testing found that this water utility exceeds health guidelines for this drinking water contaminant. Nitrate is one of the most common groundwater contaminants in rural areas. Nitrate gets into water from fertilizer runoff, manure from large animal feeding operations and wastewater treatment plant effluent. It is regulated in drinking water primarily because excess levels can cause methemoglobinemia, or "blue baby" disease. What are the risks of drinking tap water with nitrate? Cancer & Child Development. Scientists at the National Cancer Institute found a greater incidence of bladder cancer among people who drank water with nitrate concentrations above half the federal limit. Some studies also report that nitrate contamination of tap water can increase the risk of developmental defects for children born to mothers who drank nitrate-contaminated water during pregnancy. Find out more about this contaminant and how to remove it here.
3rd party independent testing found that this utility exceeds health guidelines for this drinking water contaminant. Radiological contamination of water is due to the presence of radionuclides, which are defined as atoms with unstable nuclei. In an effort to become more stable, a radionuclide emits energy in the form of rays or high-speed particles. This is called ionizing radiation because it displaces electrons, which creates ions. The three major types of ionizing radiation are alpha particles, beta particles and gamma rays. Radiological contaminants leach into water from certain minerals and from mining. What are the risks of drinking tap water with Radiological contaminants? Cancer. Over and over again, regardless of the source, long-term exposure or brief exposure in high doses, leads to cancer. Cancers of the bone, liver, stomach, lungs, skin, kidneys, thyroid gland, and most other tissues are common, and medical science is still discovering other maladies that may be cancer-related. Find out more about this contaminant and how to remove it here.
Total Trihalomethanes (TTHMs)
3rd party independent testing found that this utility exceeds health guidelines for this drinking water contaminant. Total Trihalomethanes (TTHMs) are the result of a reaction between the chlorine used for disinfecting tap water and natural organic matter in the water. At elevated levels, TTHMs have been associated with negative health effects such as cancer and adverse reproductive outcomes. Now a study by government and academic researchers adds to previous evidence that dermal absorption and inhalation of TTHMs associated with everyday tap water use can result in significantly higher blood TTHM concentrations than simply drinking the water does. What are the risks of drinking tap water with Total Trihalomethanes (TTHMs)? Cancer. Studies from around the world including the United States & Europe have found that drinking tap water that carries Total Trihalomethanes increases the risk of developing cancer. In animal studies, all trihalomethanes cause liver, kidney and intestinal tumors. Find out more about this contaminant and how to remove it here.
3rd party independent testing found that this utility exceeds health guidelines for this drinking water contaminant. Trichloroacetic acid will get into your drinking water when naturally-occurring organic and inorganic compounds found in the water reacts with chlorine or other disinfectants used to purify drinking water. Trichloroacetic acid is one of the group of five haloacetic acids regulated by federal standards. What are the risks of drinking tap water with Trichloroacetic acid? Cancer & Pregnancy Issues. According to the Environmental Protection Agency (EPA), individuals exposed to the compound in excess of the "Maximum Contaminant Levels" during the duration of several years are prone to an increased risk of getting cancer. Long-term exposure to the chemical will increase your chances of acquiring a tumor. Oral exposure or the drinking of contaminated water may cause problems during pregnancy. It can also cause developmental issues to the fetus. Find out more about this contaminant and how to remove it here.
What are the best types of filters to remove these contaminants?
Water sources can contain contaminants that impact your long term health, the taste & smell of the water and other microbiological contaminants that can actually make people sick shortly after drinking. Fortunately, there are water filtration products that remove many of the impurities from water. These filters often use activated carbon. Activated carbon is a form of carbon processed to have small, low-volume pores that increase the surface area available for adsorption of contaminants or chemical reactions. Two dominant carbon filter choices are solid activated carbon blocks and granular activated carbon filters.
Granular activated carbon filters have loose granules of carbon that look like black grains of sand. These black grains of carbon, are dumped into a container and the water is forced to travel through the container to reach the other side, passing by all of the grains of carbon. Solid block carbon filters are blocks of compressed activated carbon that are formed with the combination of heat and pressure. These filters force the water to try to find a way through the solid wall and thousands of layers of carbon until the reach a channel which leads the water out of the filter. Both filters are made from carbon that’s ground into small particulate sizes. Solid carbon blocks are ground even further into a fine mesh 7 to 19 times smaller than the granular activated carbon filters.
Flow Channels & Less Contact Time
As water continually pass through Granular Activated Carbon filters, flow channels begin to develop that allows the water to flow around the carbon. Flow channels also develop between the granules, leading to less effective filtration as there’s less contact between the water and carbon. Solid carbon blocks are much tighter and won’t even let through microbial cysts like giardia and cryptosporidium (7 to 10 Microns in size). However, solid carbon block filters are so tight that they can often get plugged up with organic & non-organic matter, forcing owners to replace them on a more regular basis. This is why when you are using a Brita water pitcher filter (granular activated carbon), the filter will keep going and going long after it has stopped removing any water contaminants.
Carbon Block vs Granulated Activated Carbon
The granular activated carbon filters are cheap and simple to manufacture, which is why most water filtration companies choose this method for manufacturing (ex: Brita, Woder). Solid Carbon Block Filters on the other hand take longer to manufacture and are more expensive but with this expense, you get superior contaminant removal because the water must take a tortured path through thousands of layers of compressed carbon before it reaches your drinking glass.
The solid carbon block filters like the one used in the Epic Smart Shield & Epic Water Filter pitchers, remove more contaminants than the granular activated carbon filters due to the larger surface area and the tighter filters, this is why Epic Water Filters has standardized on the solid carbon block design for our water pitchers and our under the sink water filter. Unfortunately, granular activated carbon filters do not do enough to reduce contaminants, this is why they are not used when there is a chance of bacteria or cysts in the water. They are truly not "Epic" so that is why we have passed on this design and let our competitors like Woder, Brita, Pur, and Invigorated Water use these loose packed carbon filters for sub-par contaminant removal.
Solid carbon block filters, on the other hand, have millions and millions of different sized pores that cause the water to take a long slow path to get through the filter, increasing the contact time that the contaminated water has with the carbon. During this contact time is when contaminants adhere to the carbon and are removed from water. This happens during a process called adsorption, the other filtration method that carbon blocks use is called depth filtration where the thickness of the filter comes into play to help remove contaminants as they have to pass through this carbon walls.
With solid carbon block filters the contaminants are in contact with more carbon for a longer period and therefore have more time to remove stubborn contaminants like lead (Epic Pure Pitcher 99.9% removal), fluoride (Epic Pure Pitcher 97.8% removal), and PFCs (Epic Pure Pitcher 99.8% removal). Carbon blocks can remove chlorine more effectively, eliminate undesirable odors, and removal of endocrine disruptors like volatile organic compounds. Granular activated carbon filters, on the other hand, have small particles that move around under the pressure of water so they do not have as much uniformity throughout and therefore less contact time with the water and less contaminant removal.
What about Reverse Osmosis?
RO filters are good at contaminant removal. The downside of RO is that it wastes a lot of water. Each RO system wastes an average of 5 to 6 gallons for every gallon it produces of drinking water. Also RO systems remove trace minerals and other beneficial substances found in water that your body needs (calcium, manganese, iron and other important nutrients). This is why RO water is considered by many in the natural health world to be dead water and it is said that demineralized water is detrimental to general health due to vitamin and mineral depletion. The last downside of RO systems is that after your water passes through the filter process, it sits inside of steel drum that is lined with a butyl rubber bladder which is made from polyisobutylene. The filtered water sits in this butyl rubber bladder until it is used. All rubber and plastic containers leach into water at some level. Carbon block filters do not have this issue.
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Impacted Zip Codes: 78201 78202 78203 78204 78205 78206 78207 78208 78209 78210 78211 78212 78213 78214 78215 78216 78217 78218 7821978220 78221 78222 78223 78224 78225 78226 78227 78228 78229 78230 78231 78232 78233 78234 78235 78236 78237 7823878239 78240 78241 78242 78243 78244 78245 78247 78248 78249 78250 78251 78252 78253 78254 78255 78256 78257 7825878259 78260 78261 78263 78264 78266 78284 78285
*3rd party review of tap water provided by this water utility was in compliance with federal health-based drinking water standards. Health guidelines, mentioned on this page, were established by independent scientists who reviewed the scientific evidence, federal and state legal limits for drinking water contaminants, health advisories and risk assessments, and incorporated them all into the health guidelines referenced here. Information on source water was obtained from city water quality reports and may be subject to change based on your location and zip code. Please consult the latest water quality report for your neighborhood or home address for more accurate information. It’s important to note that only a handful of contaminants are required to be included in annual Consumer Confidence Reports or Water Quality Reports, and that there are hundreds of potentially harmful unregulated contaminants that aren’t accounted for by the EPA. Results of tests cited here were provided to an independent 3rd party by the state, as well as test information received from the U.S. EPA Enforcement and Compliance History database (ECHO). Water is very local so it is always recommended that you test your own tap water with a 3rd party laboratory. We have found 3rd party testing available from reputable labs between $150 to $400 but we do not give recommendations for labs. Currently we have not found a home water test kit that we would recommend and it is our opinion that TDS meters are not a reliable way to test water quality.