City disinfects water to make it safe to drink
By Lynn Zerschling Journal staff writer | Posted: Sunday, March 16, 2008
City of Sioux City special projects coordinator Brad Puetz checks the chlorine content of tap water using a bench top method at the Water Treatment Plant on Tri View Ave. (Staff photo by Jerry Mennenga)
SIOUX CITY -- Turn on the tap and pour yourself a glass of cool, clear water. But before you take a sip, take a look.
See anything?
You won't.
Yet, that glass of water contains microscopic amounts of salts, metals, viruses, bacteria, pesticides, herbicides, byproducts of industrial processes, gasoline and oil. And, in Sioux City, tests have found traces of nitrobenzene, which is found in heart treatment pills. There's also the fluoride the city adds to boost healthy bones and teeth.
Is it safe to drink?
"Absolutely," declared Rick Mach, the city's water treatment plant manager. "We are pleased to report that the city's water meets or exceeds all state and federal standards."
Many of the contaminants find their way into groundwater through farm water runoff that contains pesticides, herbicides and even animal hormones. In cities, pollution comes from such things as motor vehicles leaking antifreeze and oil onto city streets or at car washes, from chemicals used to kill weeds in yards and from industrial solvents.
A recent Associated Press investigation revealed that increasingly, pharmaceuticals are found in municipal water systems. In Sioux City, however, the only drug detected in the water is a trace of that heart medicine.
"Someone takes a nitroglycerin pill and it washes through their system, ending up in the ground," Mach said.
"All those things run into rivers, lakes and streams and end up in somebody's drinking water," he said.
To treat contaminants, the water that flows out of the taps has gone through a number of treatments at the city's plant, at 1101 Tri View Avenue.
Mach pointed out the city's water quality complies with federal Environmental Protection Agency as well as state regulations governing what level of contaminants may be contained in public water systems. Required tests include screening for a small number of constituents found in drugs, Mach said, and although Sioux City asks that its water be tested for a few others, that doesn't include the full spectrum of pharmaceutical components.
"Water systems are seeing those in their water supply more and more," he noted.
At the same time, he said, technology is improving.
"We used to test for parts per million. Then we could test for parts for billion. Now, we're testing for parts per trillion," he said. "Even if we are not required to test for it, the water industry is taking the lead. The water industry isn't creating these problems. We're just trying to figure out how to treat those problems."
Testing measures
In order to detect what's hidden in the water, Brad Puetz, special projects coordinator for the treatment plant, said, "We do daily, weekly, monthly, quarterly and annual tests and do some once every three years and several every nine years. We test for nitrates and ammonia once a month."
Tests have revealed the city's water is low in salt, or sodium. State and federal regulations do not set a standard for sodium.
The city also contracts with the Siouxland District Health Department to collect water samples.
"We do 90 samples a month for bacterial samples," Chuck Cipperly, director of environmental services for the department, said. "Probably 98 percent of our samples are from businesses. We kind of rotate it around."
One of the major readings the department looks at is the chlorine level. The city adds chlorine to kill bacteria.
"We do notify them if we find the chlorine isn't quite up to par or if we find an unsafe sample. But," he emphasized, "that's very, very rare."
Most of the tests conducted at the treatment plant are computerized, although the staff uses the lab to obtain some readings. Employees staff the plant around the clock.
The treatment process
The Iowa Department of Natural Resources has classified Sioux City's water as being groundwater under the influence of surface water. That means the city has to meet certain criteria in treating the raw water.
To produce an average of 13.75 million gallons of water each day, the city operates well fields in Chris Larsen Park by the Missouri River, a new collector well in Riverside Park by the Big Sioux River and other wells, including several in Cook Park. Those wells draw water from the aquifer that is recharged by the Missouri River and from the Dakota sandstone aquifer.
At the treatment plant, the hum of machines fills the air as water swirls through a series of gigantic vats. The city uses a multipronged approach to produce safe water -- starting at those riverbanks, which filter a lot of contaminants out of the water.
After being pumped to the plant, water cascades through a series of trays to increase the exchange of gases. That aeration process helps remove iron and manganese, two naturally occurring compounds found in water.
The city adds chlorine gas to kill disease-causing organisms. Potassium permanganate is added as a disinfectant and to remove iron and manganese particles.
Water then passes through filter beds, which are made up of anthracite coal and fine sands. That helps remove any remaining suspended particles. Consequently, the turbidity of the water is below national limits, Mach said.
Turbidity, or cloudiness, is a measurement of suspended particles in water, such as iron, silt or algae. High turbidity could interfere with disinfection or may indicate problems with the filtration system.
Immediately following filtration, the water is chlorinated and sent to the contact chamber, where the chlorine is allowed enough time to disinfect the water. Then, fluoride and phosphate are added.
Because fluoridation is a political issue, Mach said a past city council authorized its use in the city's water to boost strong bones and teeth.
"In the 20 years I have been here, there were only two times people came to the council about it," he recalled. "Each time the councils voted to keep adding it to the water."
Phosphate reduces the chances that lead and/or copper will leach out of water pipes.
Then the water is pumped to the Grandview Park, 38th Street and Singing Hills reservoirs and from there, to homes and businesses.
The city sells excess water to Dakota Dunes, Sergeant Bluff and South Sioux City.
By 2010, the city will add ultraviolet disinfection equipment to kill pathogens to comply with new federal regulations. That equipment will be put in the contact chamber addition built at the treatment plant in 2004. The City Council budgeted $1.65 million in its 2010 capital improvements budget for that project.
National study
For the past six months, the city has participated in a research study on riverbank filtration.
"We were approached by the University of Arizona and University of Idaho, who are doing this study as part of a grant from the American Waterworks Research Foundation," Puetz said. "They provide us with all the filters needed, and they run all the tests. It costs us nothing other than my time."
The state Department of Natural Resources grants the city credits for the natural filtration that occurs through the riverbank.
By 2011, Mach said, the state will require the city to increase its capacity. Plans call for construction of an 11 million gallon plant in the Southbridge industrial area near Sioux Gateway Airport to augment the one on Tri View Avenue. The council has earmarked $1.2 million in the 2009 capital improvements budget, $5.4 million in 2010 and $5.4 million in 2011.
Lynn Zerschling may be reached at (712) 293-4202 or lynn.zerschling@lee.net
See anything?
You won't.
Yet, that glass of water contains microscopic amounts of salts, metals, viruses, bacteria, pesticides, herbicides, byproducts of industrial processes, gasoline and oil. And, in Sioux City, tests have found traces of nitrobenzene, which is found in heart treatment pills. There's also the fluoride the city adds to boost healthy bones and teeth.
Is it safe to drink?
"Absolutely," declared Rick Mach, the city's water treatment plant manager. "We are pleased to report that the city's water meets or exceeds all state and federal standards."
Many of the contaminants find their way into groundwater through farm water runoff that contains pesticides, herbicides and even animal hormones. In cities, pollution comes from such things as motor vehicles leaking antifreeze and oil onto city streets or at car washes, from chemicals used to kill weeds in yards and from industrial solvents.
A recent Associated Press investigation revealed that increasingly, pharmaceuticals are found in municipal water systems. In Sioux City, however, the only drug detected in the water is a trace of that heart medicine.
"Someone takes a nitroglycerin pill and it washes through their system, ending up in the ground," Mach said.
"All those things run into rivers, lakes and streams and end up in somebody's drinking water," he said.
To treat contaminants, the water that flows out of the taps has gone through a number of treatments at the city's plant, at 1101 Tri View Avenue.
Mach pointed out the city's water quality complies with federal Environmental Protection Agency as well as state regulations governing what level of contaminants may be contained in public water systems. Required tests include screening for a small number of constituents found in drugs, Mach said, and although Sioux City asks that its water be tested for a few others, that doesn't include the full spectrum of pharmaceutical components.
"Water systems are seeing those in their water supply more and more," he noted.
At the same time, he said, technology is improving.
"We used to test for parts per million. Then we could test for parts for billion. Now, we're testing for parts per trillion," he said. "Even if we are not required to test for it, the water industry is taking the lead. The water industry isn't creating these problems. We're just trying to figure out how to treat those problems."
Testing measures
In order to detect what's hidden in the water, Brad Puetz, special projects coordinator for the treatment plant, said, "We do daily, weekly, monthly, quarterly and annual tests and do some once every three years and several every nine years. We test for nitrates and ammonia once a month."
Tests have revealed the city's water is low in salt, or sodium. State and federal regulations do not set a standard for sodium.
The city also contracts with the Siouxland District Health Department to collect water samples.
"We do 90 samples a month for bacterial samples," Chuck Cipperly, director of environmental services for the department, said. "Probably 98 percent of our samples are from businesses. We kind of rotate it around."
One of the major readings the department looks at is the chlorine level. The city adds chlorine to kill bacteria.
"We do notify them if we find the chlorine isn't quite up to par or if we find an unsafe sample. But," he emphasized, "that's very, very rare."
Most of the tests conducted at the treatment plant are computerized, although the staff uses the lab to obtain some readings. Employees staff the plant around the clock.
The treatment process
The Iowa Department of Natural Resources has classified Sioux City's water as being groundwater under the influence of surface water. That means the city has to meet certain criteria in treating the raw water.
To produce an average of 13.75 million gallons of water each day, the city operates well fields in Chris Larsen Park by the Missouri River, a new collector well in Riverside Park by the Big Sioux River and other wells, including several in Cook Park. Those wells draw water from the aquifer that is recharged by the Missouri River and from the Dakota sandstone aquifer.
At the treatment plant, the hum of machines fills the air as water swirls through a series of gigantic vats. The city uses a multipronged approach to produce safe water -- starting at those riverbanks, which filter a lot of contaminants out of the water.
After being pumped to the plant, water cascades through a series of trays to increase the exchange of gases. That aeration process helps remove iron and manganese, two naturally occurring compounds found in water.
The city adds chlorine gas to kill disease-causing organisms. Potassium permanganate is added as a disinfectant and to remove iron and manganese particles.
Water then passes through filter beds, which are made up of anthracite coal and fine sands. That helps remove any remaining suspended particles. Consequently, the turbidity of the water is below national limits, Mach said.
Turbidity, or cloudiness, is a measurement of suspended particles in water, such as iron, silt or algae. High turbidity could interfere with disinfection or may indicate problems with the filtration system.
Immediately following filtration, the water is chlorinated and sent to the contact chamber, where the chlorine is allowed enough time to disinfect the water. Then, fluoride and phosphate are added.
Because fluoridation is a political issue, Mach said a past city council authorized its use in the city's water to boost strong bones and teeth.
"In the 20 years I have been here, there were only two times people came to the council about it," he recalled. "Each time the councils voted to keep adding it to the water."
Phosphate reduces the chances that lead and/or copper will leach out of water pipes.
Then the water is pumped to the Grandview Park, 38th Street and Singing Hills reservoirs and from there, to homes and businesses.
The city sells excess water to Dakota Dunes, Sergeant Bluff and South Sioux City.
By 2010, the city will add ultraviolet disinfection equipment to kill pathogens to comply with new federal regulations. That equipment will be put in the contact chamber addition built at the treatment plant in 2004. The City Council budgeted $1.65 million in its 2010 capital improvements budget for that project.
National study
For the past six months, the city has participated in a research study on riverbank filtration.
"We were approached by the University of Arizona and University of Idaho, who are doing this study as part of a grant from the American Waterworks Research Foundation," Puetz said. "They provide us with all the filters needed, and they run all the tests. It costs us nothing other than my time."
The state Department of Natural Resources grants the city credits for the natural filtration that occurs through the riverbank.
By 2011, Mach said, the state will require the city to increase its capacity. Plans call for construction of an 11 million gallon plant in the Southbridge industrial area near Sioux Gateway Airport to augment the one on Tri View Avenue. The council has earmarked $1.2 million in the 2009 capital improvements budget, $5.4 million in 2010 and $5.4 million in 2011.
Lynn Zerschling may be reached at (712) 293-4202 or lynn.zerschling@lee.net
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nyscof wrote on Mar 17, 2008 6:42 AM:
Additionally since fluoridated tap water contains 250 times more fluoride than mothers' milk, it is not to be mixed with infant formual according to the American Dental Association and the Centers for Disease Ctonrol.
With fluoride less is best, none is better
www.FluorideAction.Net "
Don't Drink the Water wrote on Mar 16, 2008 4:27 PM:
Fluoride is a poison my friends. Here are some of the risks of ingesting fluoride: A. Risk to the brain, which can effect IQ. B. Risk to the thyroid gland. C. Risk to the bones resulting in fractures. D. Risk for bone cancer. E. Risk to kidney patients who have have a heightened susceptibility to fluoride toxicity. Studies show that fluoride is only effective in preventing cavities if applied directly to the teeth, not by drinking it.
I think you will see that as our testing gets more sophisticated more and more toxins will be found in our water supplies. "