Water Quality Testing and Innovative Treatment Approaches

July 24, 2014

Consider the recent incidents of the chemical spill in West Virginia and the teenager captured on camera urinating in a reservoir in Portland, OR. Treatment becomes front and center in consumers’ minds when they hear about such things.

“The whole idea of drinking water treatment is that although we have a wide variety of sources in groundwater and surface water, you can’t drink it out of the stream,” points out Charles Hertz, who manages laboratory research at Aqua America. “If it were not for the treatment processes in place, people would be getting sick. If you look at the incidences of waterborne diseases, they went down dramatically after disinfection was added back in the early 1900s.”

Capital investments are at the center of efforts to enhance water quality by Aqua America, one of the largest US-based publicly traded water utilities. The water company, headquartered in Bryn Mawr, PA, provides water and wastewater services to approximately three million people in Pennsylvania, Ohio, North Carolina, Illinois, Texas, New Jersey, Indiana, and Virginia. There are approximately 12,000 miles of water main in the company’s entire system.

Improving supply and infrastructure is at the core of Aqua America’s approach through such initiatives as building reservoirs and treatment plants or replacing aging pipe systems to service growing communities.

Company managers believe the capital investments not only ensure reliable service and quality water for current and future customers, but also demonstrate a more fiscally efficient approach to ensuring the sustainability of its business, the industry, and the environment.

Water and wastewater operations are the most capital intensive of all utilities, requiring investment of more capital per dollar of revenue earned than any other utility, according to Aqua America. By building a robust infrastructure, the company is able to deliver quality water that meets or exceeds state and federal regulations.

Hertz points out that most of the pipe that’s been in the ground over the last 20 years is ductile iron pipe and most of it has a cement-mortar lining on the inside of it.

That’s key to sustaining water quality, adds Donna Alston, company spokesperson.

Old cast iron pipe tends to rust and there are numerous areas in the system, especially in older portions, that have many miles of old cast iron pipe, Hertz says.

“Under typical conditions, that doesn’t really cause much of a problem,” he adds. “However, if you have a quick change and reversal of the flow—like during a fire—that can stir up sediment in the pipe. That sediment is almost exclusively made of iron, which basically is the pipe rusting in on itself.”

That tuberculation of traditional cast iron—the rust build-up inside of the main—is not a problem in pipes with cement-mortar lining, Alston says, adding the lining also contributes to sustained quality and flow.

Aqua America runs a variety of tests, including operational testing and compliance testing.

“Compliance testing is a snapshot of tests that are done for a wide variety of chemical parameters and microbiology to make sure we’re in compliance with regulations,” says Hertz. “In addition to that is a slate of other tests that address secondary standards for factors such as iron, manganese, and taste and odor, and some of those things that the customer cares most about.”

Compliance testing is conducted at specific intervals as determined by the state regulatory agencies in which the water system is located, enforcing regulations according to their primacy as handed down by EPA.

“The state parameters can range anywhere from monthly for certain parameters like coliform bacteria to much less frequently—maybe every three years for other compounds, such as radionuclides,” says Hertz.

On the other hand, operational testing is conducted more frequently, ranging from weekly to monthly, depending on the parameter.

Each of Aqua America’s surface water plants have laboratories that test around the clock in addition to continuous monitors for certain parameters.

“It goes from a continuous online monitor to discrete grab sample monitors for things that are done at the treatment plant laboratories,” says Hertz. “Our lab here is a central laboratory for Aqua, and we do testing that’s much more of a snapshot. We’re also a certified lab, and one of our distinguishing factors is that treatment plant labs, at least in Pennsylvania, are typically not certified, although they may be in other states. We have all sorts of fancy instrumentation for analysis of all types of chemicals.”

The lab tests for standard parameters such as metals and minerals in its inorganic chemistry lab and a variety of organic chemicals at varying frequencies for specific reasons, says Hertz.

“The things we do that a lot of different utilities do not do are focused on taste and odor compounds,” he adds. “These are aside from all of the things that we test for to be in compliance with the regulations. The parameters that we’re looking for in organic compounds are in microgram per liter concentrations if present at all. And people wouldn’t know if they’re there or not.”

An algae bloom in a river or reservoir, which is accompanied by an earthy, musty-type odor, can elicit a lot of customer calls, says Hertz.

“Our research lab has the capability of looking for specific taste and odor compounds by a different method than a lot of utilities use,” he says. “We can look for things in nanogram per liter concentrations or parts per trillion levels, and we do that because it’s important to our customers.

“We want to put out the best possible water, and when we get a lot of calls where people are concerned about the taste and odor of the water—even if it’s not harmful—the perception is there.”

Two Incidences of Contamination

Other times, an odor can herald the presence of something amiss, such as when residents in Charleston, WV, noticed a strange odor, something that smelled like licorice.

That odor was the evidence of the chemical spill of crude 4-methylcyclohexanemethanol (MCHM) from Freedom Industries, a facility that distributed chemicals used for coal mining, into the Elk River in West Virginia in January. The spill occurred upstream from the main West Virginia American Water intake and treatment and distribution center.

Twelve days after the spill, Freedom Industries announced the presence of a second chemical in the water: a proprietary mixture of glycol ethers called PPH. Only two out of 300 samples showed traces of PPH, taken while residents were under a “do not use” order.

As a result of the chemical spills, nearly 300,000 residents in nine counties were without access to potable water.

In testimony to the House Transportation and Infrastructure Committee, Jeffrey McIntyre, president of West Virginia American Water, indicated that after his water company learned of the spill from the West Virginia Department of Environmental Protection, it took immediate steps to learn more about the chemical, augment its treatment processes in the Kanawha Valley plant and begin consultations with officials from the local to the federal level.

After the company’s water quality team determined the augmented treatment process was not fully removing the chemical, a “do not use” order was issued in conjunction with the West Virginia Bureau of Public Health.

The company would continue to conduct testing for MCHM and flushing the water for ensuing weeks until it was determined that the chemical was at a “non-detect” level in the system at less than 10 parts per billion. More than 2,500 analyses had been conducted since the spill had occurred.

“That whole perception thing is very important and in the example in West Virginia, that situation where they were without water and not able to drink it for more than a week caused big, big problems,” points out Hertz.

In another incident, the Portland Water Bureau made the decision to take its 50-million gallon Mt. Tabor Reservoir 5 offline and test for possible contamination after a teenager urinated into the reservoir. The test samples came back clean. The city’s decision to dump 38 million gallons of treated water following the incident drew some public criticism from around the nation, but David Shaff, the bureau’s administrator, told the media its primary goal is to provide clean, cold, and constant water to its customers, which also means it doesn’t contain urine. He also said while animals deposit waste that doesn’t create a public health crisis, the city has plenty of water to meet demand.

Aqua America’s focus on taste and odor compounds includes a treatment process using powdered activated carbon at all of its surface plants every day, Hertz says.

Two plants in Pennsylvania also feature a process that uses UV and peroxide to oxidize taste and odor compounds.

“They were installed specifically to get rid of certain types of these algal metabolites that cause that earthy, musty-type odor,” says Hertz. “We’ve had it in Bucks County for the last two years, and it has been successful at attenuating those metals.”

There are challenges in water quality testing of the varying water quality coming down the stream, says Hertz.

“The treatment plants do a fine job with it,” he says. “In a surface water plant, although we do have watershed control and source water protection activities, there’s not a whole lot we can do with the water coming down the stream that we’ve treated as best we can.

“That varying water quality with the varying conditions like heavy rain will definitely have an impact on the water quality in the stream and can present a treatment challenge depending on what is washed in.”

During the past winter, there were issues with the chemicals that various municipal transportation departments were using to treat for ice, Alston says.

The summer brings the algae blooms.

“They can be particularly difficult to treat because there are some people who have some sensitivity to those tastes and odors in that they can taste the parts per trillion,” says Alston. “A reporter for one of the local papers is one of the people who has this sensitivity and many times, she would indicate to us that we were having the start of an algae issue because she could actually taste 15 parts per trillion. While every once in a while you have an unfortunate man-made incident like spills, Mother Nature can present challenges on her own sometimes.”

Disinfection and Infrastructure
When preparing to rehabilitate a pipe, Aqua America conducts various tests before and during the process, says Hertz.

Credit: AQUA AMERICA
Ductile iron pipe with cement mortar lining has undergone disinfection before it is put in the ground.

“We do testing to make sure that the pipe is adequate to put into service,” he says. That may entail a standardized protocol in which the water main is disinfected and put through a three-part test on two successive series of tests to make sure the water is OK before it is released to the customer.

“That’s an extremely important part of the rehab process because we don’t want to put pipe in the ground that we’re stuck with for the next 100 years, and it has to pass the lab testing,” says Hertz. “We probably do over and above what other utilities do, but we feel it’s worthwhile because you really only have one chance to get it right when you disinfect the pipe.”

Aqua America’s wastewater treatment is similar to that of other operations in the country in that it undergoes a settling process and biological degradation to degrade the parameters in the raw water.

“You’re trying to get rid of the solids and degrade the oxygen demand through the things that are causing oxygen demand in the raw water,” says Hertz.

Company-wide, Aqua America spends about $300 million on infrastructure through capital projects, says Alston.

“The challenges that many of the municipal companies face of getting the customers to understand the true cost of water has led to deferrals of water and wastewater infrastructure that we’re trying to manage and cope with today,” she says. “There is a real misunderstanding about the value of water and at what cost it comes. When you look at water rates around the country, most people pay a lot less for water than they pay for cable TV.”

Yet water is the only “utility” that is ingested, and the only one that one absolutely must have to live, she adds.

“You may be able to afford to live without electricity for a while, but you’re absolutely going to need water,” points out Alston. “I think there is a real need for all of us to further educate our customers and citizens when you consider it’s the most capital-intensive of all utilities–water utilities have to invest more capital dollars per dollar of revenue earned than any other utility, and still most people probably pay less than $50 per month for water. Wastewater suffers from the same challenge and the actual cost of wastewater treatment I would suspect is probably higher.”

Hertz says even though the treatment is less rigorous by its nature for a groundwater source, the surface water sources “really need treatment. We do a lot more testing both at the treatment plant and at our central lab to ensure that water is potable.”

Arsenic, Iron, Manganese, and Hydrogen Sulfide
The Village of DeWitt, IL, is home to 200 residents and had an outdated filter system that did not meet regulatory compliance. Berns, Clancy, and Associates contacted AdEdge in 2011 to design, manufacture, and start up an arsenic, iron, manganese, and hydrogen sulfide removal system for the Village of DeWitt.

Prior to the full-scale system, AdEdge commissioned a pilot study in January 2013 to verify the treatment approach due to

Credit: AQUA AMERICA
Infrastructure requires capital and is key to water quality.

the challenging water chemistry. The raw water contained high levels of phosphate, ammonia, TOC (total organic carbon), hydrogen sulfide, iron, manganese, and arsenic.

The AdEdge treatment system was designed for a maximum flow of 50 gallons per minute. The system is comprised of four 24-inch carbon steel vessels arranged in a parallel configuration. The vessels are loaded with AdEdge’s AD26 oxidation/filtration media for the removal of arsenic, iron and manganese, and hydrogen sulfide. AD26 media is a NSF 61 certified manganese dioxide based filter media. The high filtration rate of the AD26 media allows for the removal of

the contaminants while maintaining the existing building’s small footprint.

The AD26 media in the presence of a strong oxidant, which is injected into the raw water, acts as a catalyst for the accelerated removal of the contaminants. The programmable logic controller (PLC) initiates an automatic backwash of the treatment vessels to remove any precipitated solids that may accumulate in the media bed and to extend the life of the AD26 media.

Backwashing of the treatment vessels occurs one vessel at a time to ensure water is continuously being treated throughout the day. The system fully integrates with the existing post-chlorination system that addresses the high ammonia levels in the water before going to distribution.

Credit: SENSOREX
Sensorex meters may be used in labs or the field.

The treatment system was successfully commissioned in July 2013. More than 30,000 gallons of water are treated on a daily basis. The levels of arsenic have lowered from 0.020 mg/L to non-detectable levels. The iron and manganese levels are reduced from 5.3 mg/L and 0.12 mg/L to below the treatment goals of 0.3 mg/L and 0.05 mg/L, respectively. Hydrogen sulfide has also been lowered to a non-detectable level.

Wastewater Reuse at Audubon
The Audubon Society sought to construct an environmental education center in the Ernest E. Debs Regional Park in Los Angeles, CA, to serve as a model of green architecture and the first Leadership in Energy & Environmental Design (LEED) Platinum-rated facility in the world.

One of the criteria in doing that was a wastewater reuse option.

Enter Steve Braband, company president of BioSolutions, a company that provides products and services for the wastewater industry, specializing in providing complete site-specific packages for decentralized wastewater, one of which is an Orenco-manufactured AdvanTex Textile Treatment System.

The Audubon Society got the city’s approval to go off of the sewer grid to capture, treat, and reuse wastewater with the system. The quality of the treated water is high enough to be reused for subsurface drip irrigation.

In January 2004, the Audubon Society earned 53 LEED points and was awarded the first Platinum rating in the history of the LEED program. High marks came through the use of the efficiency of the AdvanTex wastewater treatment system. Of particular note is that the center was designed to use 70% less water than a comparable conventional building and that the wastewater is being treated onsite.

The wastewater from the 5,020-foot building flows to a processing tanks for settling and initial filtration, then moves through several AdvanTex pods filled with an engineered textile material for secondary treatment to high standards.

Next, it is disinfected and used for subsurface irrigation as well as toilet flushing. The system is monitored around the clock by a remote telemetry control.

The facility has 1,200 gallon per day design peak flows. The primary treatment takes place in a 5,000-gallon two-chambered septic tank with solar-powered pumps. The secondary treatment occurs in three AdvanTex Textile Filters.

The system is equipped with an Orenco VeriComm Control Panel and Monitoring System.

The water is so clear that tour guides will show a sample to visitors that demonstrates it is as clean as drinking water, says Braband. The effluent quality is 5 mg/L BOD and TSS.

The system is located in a roundabout at the front entrance of the facility.

“Initially, we wanted to put it on the side of the facility out of the way of general public, but that happened to be right under the window of the general manager and she had negated the idea of placement there for fear of odors when she opened her window,” says Braband.

The general manager had wanted the facility to be pushed out as far as possible, which placed it at the front. As a result, everyone saw it as they were entering the facility.

“AdvanTex is known for not having any odors, and because of the low energy, the efficiency, and the high water quality, it turned out to be part of the tour of the facility,” says Braband. “They would go out there, open up the system, and go through how it works. They would pull a sample and compare it with a sample taken out of bottled water, and challenge people to indicate which one was the treated water versus the bottled water.

“We took a deficit of something being pushed away from the property and turned it into an asset in the sense that it turned out to be a showcase for sustainability.”

Braband has given trainings and tours for regulators, utilities, public officials, and others working on LEED projects. As a result of a tour, representatives of the Goleta Water District north of Santa Barbara purchased an AdvanTex system and earned a LEED Silver rating.

A decade after its installation, the onsite treatment facility on the Audobon property has virtually “disappeared” as trees have grown around it. “There are still pathways in there to do operation and maintenance,” says Braband. “It’s highly successful. It’s been taking the intermittent flows very well and the water quality remains very good.”

Braband sees the Audubon Education Center as a springboard for future projects. “We’re looking at sustainability in southern California,” he says. “We’re starting to take the decentralized wastewater technologies into the sewered areas for treated graywater reuse for subsurface drip irrigation and for toilet reflush.”

Decentralized wastewater systems are beneficial in reducing the reliance on potable water for functions that can be handled by highly treated wastewater and without a heavy investment into purple pipe infrastructure, Braband points out.

“In southern California, some municipal water utilities do take Title 22 recycled water, but as the city of Los Angeles has recognized, it’s very difficult to run a second line back for recycled water through the city,” he says.

“You would have pockets of golf courses, schools with athletic fields, and parks where we would like to have recycled water, but to do that, we would have to run dedicated recycled pipes back.”

Communities are starting to consider the use of small decentralized plants–“like sewer harvesting,” says Braband–where they would take a portion of the sewer system and capture it at that point and use a decentralized technology to treat to a recycled standard and reuse the water locally for golf courses, parks, and other areas.

Water quality can be obtained through various approaches, says Braband.

“With this particular product, we used the primary as an anaerobic digester initially, and with the type of attached growth system we utilized, we have good success with fluctuating flows,” he says. “You have peak flows on the weekend; you might have slow flows throughout the week. This is a very robust system that allows us to have high quality of flow in fluctuating flows.”

Tools and Approaches
Harbans Lal, an environmental engineer with the Water Quality and Quantity Team of the West National Technology Support Center for the United States Department of Agriculture–Natural Resources Conservation Service in Portland was part of a team of scientists who developed a Web-based tool to help agricultural producers understand the quality of water flowing off their fields: the Water Quality Index for Agricultural Runoff. Based on several parameters, it provides a single number representing overall water quality at a certain location and time.Approaches to testing for water quality always depend on its use, he says. “Is it basically for drinking, for swimming, recreation? All of those purposes have their own water quality standards for different pollutants, so it all depends on what the purpose is and how you want to monitor the water quality with a variety of tools and techniques.”

In the DeKalb Sanitary District in DeKalb, IL, Allison Yates, the laboratory supervisor, does all of the testing of the wastewater, which comes in at five million gallons a day. She tests for BOD, ammonia, suspended solids, and pH, the latter of which she uses Sensorex technology for analysis.

“We have a permit through the EPA, and we have to fall within the various limits they give us–if we don’t, we get violations,” points out Yates.

The Sensorex meter used by Yates is the SAM-1 Smart Aqua Meter. The instrument is compatible with Apple iPads, iPhones, and iPods, as well as Androids—using those smart devices to measure and record pH, ORP, conductivity, and temperature values.

SAM-1 is designed to deliver accurate analytical measurements in the lab or field for use in environmental, educational, and industrial applications.

It plugs into the headphone jack of a smartphone or tablet and connects to Sensorex smart analytical sensors for measurement.

The SAM-1 app is available as a free download and instantly recognizes the smart sensor type and calibration data. Time, date, and GPS location are automatically recorded with each reading. Users may add location name and additional comments.

Readings can be shared via e-mail or exported to a spreadsheet for analysis and record retention.

The Sensorex meter is one tool used by Yates, who says her biggest challenge is when some tools won’t work. “Another challenge is you never really know the results you’re getting are right,” she says. “You just hope that the equipment you’re using is working correctly, and you have to watch to make sure for any outlying results you get that something might be going wrong with some of your equipment.

“If it is, it’s a big ordeal. It’s not just “˜turn off and start it again.’ I’m the only one in here, so I’m responsible for everything, and being that we are regulated by the EPA, it’s a big responsibility to have.”

The DeKalb Sanitary District is in a university town hosting Northern Illinois University. That means flows can vary.

“There are thousands of students here most of the time and then they’re not here for a week or the summer,” says Yates. “Everything calms down here and then the week the students come back from summer vacation or spring break, things change again, and you have to adjust to that.”

In the treatment plant, centrifuges spin and separate solids at different sections of the plant. The solids are frequently applied to farmland as a fertilizer and the effluent goes out to the Kishwaukee River.

The district is in the process of using some of the methane gas to power and heat some of its digesters. Another plan is to use food scraps from Northern Illinois University in the digesters instead of hauling them to the solid waste facility, using that to make more methane gas to power the plant.
About the Author

Carol Brzozowski

Carol Brzozowski specializes in topics related to resource management and technology.