Sources Of Drinking Water in Tempe, Arizona
Where does Tempe get its water from? In 2017, the drinking water in Tempe was produced at two conventional surface water treatment plants and ten groundwater wells. The Johnny G. Martinez Water Treatment Plant is located at 255 E. Marigold Lane. The South Tempe Water Treatment Plant is located at 6600 S. Price Road. The City of Tempe provides water to its customers from several sources: Central Arizona Project (CAP) water – Beginning its journey from Lake Havasu, Colorado River water is delivered through the CAP canal system to central Arizona, including the Phoenix and Tucson areas. Tempe used 1.3 billion gallons billion gallons (or 3.5 million gallons per day) of Colorado River water delivered by CAP for municipal use in 2017. Salt River Project (SRP) water – This water is collected from the Salt and Verde River watersheds, stored in six SRP reservoirs and diverted into SRP canals at the Granite Reef Dam in Mesa.
SRP also relies on groundwater wells to supplement surface water in the canal system. Tempe’s allocation of SRP water depends on the amount of runoff from the watershed and the amount of water available in storage in SRP reservoirs, and therefore varies from year to year. Tempe’s SRP water use for 2017 was 12.5 billion gallons (or 34.2 million gallons per day). Groundwater – In 2017, Tempe used ten of its groundwater wells to supplement the supplies of Central Arizona Project water and Salt River Project water. Tempe pumped 3.7 billion gallons (or 10 million gallons per day) of water from its wells, which was a combination of groundwater and surface water previously stored underground in our aquifers. Is Tempe's water safe to drink? Does Tempe put fluoride in its water?
Source: City of Tempe
Contaminants Found in Tempe's Water Supply
(Detected above health guidelines)
3rd party independent testing found that this utility exceeds health guidelines for this drinking water contaminant. Arsenic occurs naturally in soil and bedrock in parts of the United States. Commercial activities that could have left arsenic in our soil and water include, apple orchard spraying, coal ash disposal, use of pressure treated wood. Arsenic has no smell, taste, or color when dissolved in water, even in high concentrations, so only laboratory analysis can detect its presence and concentration. What are the risks of drinking tap water with arsenic? Cancer. Chronic exposure to arsenic is also associated with an increased risk of skin, bladder, and lung cancer. There is also evidence that long-term exposure to arsenic can increase risks for kidney and prostate 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. Perfluorinated Compounds (PFCs), also referred to as perfluorinated alkyl substances (PFASs), are a large group of environmentally persistent manufactured chemicals used in industrial applications and consumer products (ex: Teflon, Gor-Tex). PFCs are very stable, slow to degrade in the environment. PFCs are highly soluble in aquatic environments and can dissolve into water from various sources. Due to their chemical and biological stability, PFCs are difficult to degrade via biodegradation, photolysis, or hydrolysis. They are most often found near industry discharge points where they have been used. Currently there are no enforceable federal drinking water limits for PFCs. What are the risks of drinking tap water with PFCs? Endocrine Disruption, Reproductive & Child Development Issues. PFCs are considered toxic and can lead to potential adverse health effects in humans and wildlife. Animal studies show that increased exposure to high concentrations of PFCs may cause abnormal endocrine activity, and reproductive and developmental problems. 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. 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. 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.
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.
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 these issues.
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