Improved water treatment and water quality techniques are helping drought-stricken regions to turn wastewater into an alternative resource.
By Dan Rafter
Since 2008, residents of Orange County, CA, have been drinking potable water that originally started as wastewater. It’s an example that provides hope for those who argue that reusing treated wastewater for a wide variety of uses—including, perhaps most importantly, drinking water—is a necessity as water becomes scarcer in more arid regions of the United States.
In Orange County, the Groundwater Replenishment System (GWRS)—a joint effort by the Orange County Water District (OCWD) and Orange County Sanitation District—recycles wastewater after treating it to a level exceeding state and federal drinking regulations. The treated water is released into area groundwater recharge basins. Once there, the water is tapped for a variety of uses.
One of the uses? As drinking water delivered to the residences and businesses of Orange County.
This is an improvement over the days when treated wastewater was simply discharged into the waters of the Pacific Ocean. It was a necessity, too, according to Mehul Patel, program manager for the Groundwater Replenishment System and principal process engineer for the OCWD.
Before the GWRS went online, Orange County faced two daunting water issues: it was importing too much of its water from an outside source, the Colorado River system, and water sources in northern California. Secondly, its main local source of water, the Santa Ana River in Orange County, was suffering from decreased flows because of dry conditions.
|Photo: ORANGE COUNTY WATER DISTRICT, COURTESY OF AWWA AND PHOTOGRAPHER STEVE CRISE
Microfiltration cell in the GWRS
As Patel says, Orange County needed more control over its water.
“We wanted an alternative source of water that we could control,” says Patel. “We wanted a source that we could produce for a reasonable price. Imported water comes at a premium price, and we were importing too much outside water. If we were proactive—if we could find another source of water we could control—we wouldn’t have to rely so heavily on imported water. We needed a way to hedge our bets for the future, especially if the Colorado River water levels kept going down.”
The replenishment system has accomplished this. But before Orange County officials could make this a reality, they had to overcome the “ick” factor, the natural revulsion consumers experience when hearing that they’ll be drinking water that was once wastewater.
Fortunately, Orange County’s success shows that the “ick” factor is not an insurmountable barrier. There are several reasons why reusing treated wastewater is becoming more common, and as awareness of water scarcity grows, reuse is no longer an option, but a necessity, in areas of the country like the arid Southwest, including California, Nevada, and Texas.
But there have also been dramatic improvements in the way municipalities and other water providers treat, monitor, and test their water quality. And these improvements are helping to ease the concerns of end users. As in Orange County, reused wastewater is treated to ultra-pure levels. In short, treatment technologies make sure that this water is as clean and safe as possible.
“As a society we are becoming more environmentally conscious,” says Richard Cavagnaro, marketing manager for AdEdge Technologies in Buford, GA. “We are becoming greener, we are focusing more on sustainability. Those are concepts that are now mainstream. And this means that more people are looking at ways to sustain water, which is one of our most valuable resources. As part of that, more people are willing to consider reusing treated water, even for drinking water.”
This is good news, not only for the manufacturers of treatment technologies, but also for the planet as a whole. And Cavagnaro and others in the treatment and testing business say that the reuse trend isn’t about to lose its momentum.
“It’s all about awareness,” says Cavagnaro. “It’s about companies and municipalities promoting that treated and reused water is acceptable, and that it is safe. We’re also seeing more success stories. After seeing something work six times, it starts to become widely accepted. That’s what is happening with treated and reused water.”
Improved Technology Is the Key
Water reuse supporters received good news in early 2012. That’s when a report from the National Research Council says that, thanks to advances in technology, treated wastewater—often called reclaimed wastewater—was at least as safe as traditional drinking water. The report also says that treating wastewater and reusing it for drinking water, irrigation, industry, and other uses could dramatically increase the country’s available water resources. This, the report says, is particularly important in coastal areas facing water shortages.
What spurred the optimistic tone of the report? Improved water treatment, monitoring, and testing technology, which has made it possible for municipalities and utilities to create ultra-pure water from wastewater streams.
“Wastewater reuse is poised to become a legitimate part of the nation’s water supply portfolio given recent improvements to treatment processes,” said R. Rhodes Trussell, chair of the committee that wrote the report, and president of Pasadena, CA-based Trussell Technologies, in a written statement. “Although reuse is not a panacea, wastewater discharged to the environment is of such quantity that it could measurably complement water from other sources and management strategies.”
The report looks at a wide range of reuse applications. Committee members found that many communities across the US have already launched less-controversial reuse projects. Many, for instance, use treated wastewater to irrigate golf courses and parklands. Others use it to provide cooling water to industrial users.
Though many communities have been slow to embrace the use of treated wastewater as a supplement to potable water supply, this reticence is starting to diminish.
Anupam Bhargava, chief executive officer of Middletown, CT-based Dolphin WaterCare, says that his company is gaining customers because of the increased demand for reused water. Dolphin specializes in chemical-free water treatment. This means that water treated with Dolphin WaterCare’s equipment is easily reusable.
“We are finding more customers taking discharge water from their cooling systems and reusing it for secondary purposes such as irrigation,” says Bhargava. “We have customers from California to Dubai doing this.”
Many of Dolphin WaterCare’s customers are commercial businesses such as office towers and industrial buildings. This class of user consumes a significant amount of water each year, says Bhargava.
“When we think of water, we think of residential users or agricultural users,” he says. “But the reality is that commercial/industrial buildings consume more than 10 billion gallons of potable water daily. Much of that water goes into the cooling system of a building. That’s an invisible water consumption that no one thinks about.”
But when commercial buildings reuse water, they can make a significant impact on the availability of water in this country, says Bhargava.
He points to an office campus in California in which 100% of the water used for irrigation on the site comes from the wastewater generated from a cooling system.
“When you are treating cooling water with chemicals, you can’t do that as a business,” says Bhargava. “You run into efficiency issues. There’s a cost that goes with reusing wastewater that’s been treated with chemicals. There’s a cost, too, with water that must go to a wastewater treatment facility and isn’t being reused. We think this will grow in importance with customers in the coming years.”
Bhargava’s hope is that more industrial and commercial users will turn to non-chemical-based methods of treating water. If they do, they’ll be more likely to reuse their treated water, something that will have a long-term positive impact on the water-scarcity issues facing the country, he says.
“The global impact it can have if industry switches from chemical to non-chemical water treatment can be immense,” says Bhargava. “It can be quite significant. We think the time is right to accelerate the adoption of non-chemical water treatment.”
Graham Symmonds, chief technology officer and senior vice president of regulatory affairs and compliance with Phoenix-based Global Water Resources, says that municipalities have always been aware of how important it is to monitor, treat, and test water. End users have been, too, Symmonds says. But these end users haven’t always given much thought to how their water was treated.
“For end users, they typically only care that the water comes out of the tap in a safe and reliable manner,” says Symmonds. “They don’t usually know what goes on behind the scenes.”
That attitude, though, doesn’t necessarily help the water industry when it comes to recycling treated wastewater. It’s easier for consumers to fall victim to the “ick” factor if they don’t understand the complicated processes that go into treating, monitoring, and testing water, especially treated wastewater before it’s released back into the system for irrigation or drinking purposes.
|Photo: CLEARWATER SYSTEMS/DOLPHIN CARE
Discharge water for cooling systems
is increasingly being reused for
secondary purposes, like irrigation.
Symmonds says that it’s up to the water treatment industry to do a better job of explaining to end-users exactly how water is treated. This could help make recycled wastewater an easier sell; consumers might be less averse to water reuse if they understand just how rigorous the purification process of this water is.
“We need to communicate what it takes to find water, take out what needs to be taken out, and deliver it,” he says. “People just expect the water to be there when they turn on the tap. But maybe people would better appreciate water if they had to walk three miles to fill a five-gallon jug like they do in some parts of the world. If you had to do that, you’d understand how important water is, and how valuable a resource it is.”
The problem? The engineers who work most closely with water treatment technologies aren’t always the best communicators. It’s a problem that the treatment industry must overcome if it hopes to sell its latest technologies and reuse plans, Symmonds says.
“I’m an engineer; I understand how it is. We like to work in the background,” says Symmonds. “We like to be the invisibles. We provide water, and we take away waste. The best we can hope for is that you never notice us. But what is now true is that it is incumbent upon us as water officials to get the word out there more. We are the ones who understand what is going on behind the scenes, and we have to share our knowledge with others if we want to get more support from end users for our initiatives.”
As more municipalities deal with water shortages, it’s important for water industry officials to educate consumers on how much water they are actually consuming, Symmonds says. This, too, can help convince end users to support everything from basic water conservation efforts to water reuse systems.
This is why Global Water Resources has long been a proponent of monitoring software that gives end users real-time information about how much water they are consuming on a daily, weekly, and monthly basis. When consumers see exactly how much water they are consuming, they are often willing to make changes.
And changing the way consumers use water is as important a part of any community’s water-use plans as are treatment, monitoring, testing, and reuse technologies. Symmonds says that when consumers are given access to real-time water-usage data, they tend to reduce their water consumption by 10 to 15%. End users tend to consume less water just by receiving their water bills electronically versus traditional paper mail, Symmonds says.
“People don’t understand how much water they use,” says Symmonds. “They think they just drink eight glasses a day. But they don’t think about watering their lawns, washing their clothes, and washing their dishes. By providing continuous feedback on consumption, you can start to help end users understand how much water they are using. Part of the problem is that water districts tend to bill their end users in arrears. When you do that, you don’t have the opportunity to impress upon people how their actions impact their own personal consumption. With real-time data, though, you can make that connection.”
|Photo: CLEARWATER SYSTEMS/DOLPHIN CARE
Increasingly, commercial and industrial
facilities are turning to reuse for
their secondary water needs.
Symmonds is optimistic that a variety of factors—everything from real-time water usage data, to increased communication about water scarcity issues—will encourage more communities to adopt more creative water conservation methods. And these methods, he says, will certainly include a greater reliance on water reuse facilitated by improving treatment technology.
“It’s always been a challenge to get people to accept water reuse for drinking water,” says Symmonds. “But it is becoming less of one. In a water-shortage crisis, most people would say, ‘OK; we’ll take it.’ Some people never will. It’s all about how you communicate with the public and whether the public has trust in its water suppliers.”
Big Changes in Orange County
Reused water is already making an important impact in Orange County. Patel, from the Orange County Water District, says that the Groundwater Replenishment System provides 70 million gallons of recycled water each day. That’s the equivalent of 72,000 acre-feet of water a year.
Considering that a single acre-foot of water is enough for two families of four, it’s easy to see the impact that the replenishment system has had in southern California. As Patel says, it provides enough recycled water for about 500,000 people every year.
Of course, this doesn’t mean that the replenishment district is now the main source of water for Orange County. The population here is large, with more than three million people calling the county home in 2011. Still, the replenishment system is allowing the county to import less outside water. Patel says that the recycled water accounts for about 20% of the county’s water supply today. That’s 20% that county officials don’t have to import or drain from their local water sources.
The project is even more important when you consider that demand for water has increased in Orange County since the replenishment district went online in 2008.
“We have been able to keep up with demand without having to purchase more imported water,” says Patel. “At the same time, we have been able to maintain the same level of pumping, even with demand going up. That saves the end user. End users’ bills will not go up significantly. If more of our supply can come from groundwater, we don’t have to charge the end users as much.”
El Paso, TX, is no stranger to water shortages. Even when the region isn’t being hit by drought conditions, water is a scarce resource. It’s little surprise, then, that this area, like Orange County, has become a leader in the reused water movement.
El Paso Water Utilities has been delivering reclaimed water since 1963. It now operates one of the largest reclaimed water systems in Texas, sending treated wastewater to be used for industrial uses and landscape irrigation.
And El Paso utility officials are continually boosting their water reuse efforts. The utility’s Northwest Reclaimed Water Project is now under construction. This $23 million system already provides more than 520 million gallons of reclaimed water each year, water that travels through 26 miles of pipeline. The project already provides recycled water to contractors and others to be used on construction projects, street sweeping and other jobs. New extensions are now being completed to provide reclaimed water for schools, parks, and commercial properties.
Christina Montoya, vice president of communications and marketing for El Paso Water Utilities, says that the utility provides 2.2 billion gallons of reclaimed water each year. This has attracted the attention of other utilities and municipalities, she says.
“We get asked to speak at conferences all the time,” says Montoya. “We are happy to offer our expertise and talk about water reuse. There are other communities looking at what we do.”
Communities are also interested in how to convince their residents that treated wastewater is acceptable as drinking water. El Paso can address this. Since 1985, the utility has been pumping treated wastewater into an aquifer. The utility then pulls out this water to use as drinking water.
“We did a lot of community outreach to get our residents to accept this,” says Montoya. “Today, people here are accepting of it and proud of it. It’s very innovative. Back in 1985, we were one of the first in the nation to try this. We are now known nationwide as being innovative and trying new things. People see the challenges that come with drought. They understand, especially in Texas, that we need to look at other sources for water. The science is there.”
El Paso utility officials hope to, in the future, increase the amount of reclaimed water in their system, for everything from irrigation to industrial use, to drinking water, says Montoya.
“Our belief is we shouldn’t use the water only once with us being in an arid city,” she adds. “We’ve always looked to diversify our water portfolio, to not rely on just one source of water. The more reclaimed water we can use, the less potable water we will be using.”
Author’s Bio: Dan Rafter is a technical writer and frequent contributor.