How to Overcome the "Yuck" Factor of Recycled Wastewater

For those of us who live in places where there is never any doubt about the ability to turn a tap and have clean water come out, it can be hard to reconcile the reality that the world is at great risk of a water supply crisis. In 2023, the UN estimated that not only do two billion people not have safe drinking water, but that two to three billion people are already experiencing water shortages for at least one month a year. The report also projects that the population facing urban water scarcity will double by 2050, due to the increasing frequency of extreme drought.

And drought isn’t the only supply issue — many groundwater aquifers have been overpumped for decades. The Ogallala Aquifer, the largest in North America, supplies 30% of the irrigation water in the United States, is the only reliable source of water in some parts of the American heartland, and will run out of water in a generation in the most vulnerable communities.

So what are we to do about our water supply problems? Yes, we could and should certainly try to use less water, look for other surface water sources, or even pump water back into depleted aquifers.

We could also recycle our wastewater. But, well. That seems “yucky” to a lot of people.  

In Tampa, former Florida state representative and state senator Janet Cruz lost an election in 2023 to the Tampa City Council, largely attributed to her support of laws allowing treated wastewater into drinking water systems while she was a state legislator. In a survey conducted for research published in the Science of The Total Environment journal last year, it was found that just 43% of respondents in the Southeast US supported water reuse generally — and only 8% would be willing to drink recycled water.

But the fact of the matter is that the rest of our water sources cannot be relied upon as we continue to use them in unsustainable ways, and the total volume of our wastewater represents an invaluable opportunity to reshape our water future, if we can just get beyond that “yuck factor.”

To that end, the State Water Resources Control Board of California voted in December 2023 to adopt regulations to implement direct potable reuse (DPR) in the state — in other words, that means treating wastewater to the point that it can be added directly into drinking water systems, with no environmental buffer. The vote was years in the making and the development of the regulations mandated by state law.

California, with its population of 40 million and extremely high demand for agricultural irrigation water, faces the stresses of water supply perhaps more than any other state. The move to implement DPR follows decades of indirect potable and non-potable reuse in the state (and many others in the country, like Florida). Treated wastewater is already being used for industrial machines, irrigation, and aquifer replenishment.

At the time the legislation went through, the Metropolitan Water District alone (the water agency of Southern California) was projected to provide 115 million gallons of recycled water a day by 2032, which could supply 385,000 homes. Gov. Gavin Newsom projected that recycled water could account for 9% of state water use by 2030 and then double by 2040.

The statewide regulations officially allowing for DPR in California went into effect in October of last year. By then, cities like Santa Monica were hoping to implement DPR as early as 2027. Plans for a full DPR treatment facility in the San Fernando Valley to be completed by the same time point are underway. These rules also allow water agencies flexibility in their supply management between wet and dry years, meaning that the objective is that drinking recycled water will help the agencies save water from the Colorado River and Sierra Nevada snowpack for drier years.

But for all the high hopes in California, the state won’t be the first in the nation to treat its wastewater to drinking water quality. The city of Big Spring, Texas, was the first place in the country to use DPR to supply its water system, which it began in 2013 after its namesake spring ran out of water. The standard bearer of water recycling, though, is Singapore, which through its Changi Water Reclamation Plant cleans 237 million gallons of wastewater a day and brands the treated water as “NEWater.”

And California won’t likely be alone as the sole mass consumer of wastewater-turned-drinking-water in the US either. The city of El Paso is expected to have a DPR plant online by 2027, as Texas allows such plants on a case-by-case basis. Colorado actually beat California to adopting DPR regulations in February of 2023, which were the first in the nation. And despite Cruz’s loss in the Tampa City Council election, the practice is still moving forward in Florida, where a pilot program in a central Florida county began turning wastewater to drinking water in late 2023.

Finally, Arizona also began building a framework for DPR late 2023, where the need is increasingly being seen as inevitable. The state’s proposed rules are nearing approval.

Of course, building the needed facilities and the extensive water treatment process won’t come cheaply, especially for municipalities that aren’t quite the size of the whole state of California or even just El Paso. The DPR facility constructed by the Colorado River Municipal Water District for Big Spring, which has a population of around 25,000, cost $14 million to build and took 11 years to plan and construct. Getting other smaller communities on board before it’s absolutely necessary will likely not be easy.

But getting the infrastructure for DPR and other expanded water recycling systems in place now will be cheaper than in the future, when other water sources are even more stressed. And as with all things, as the wastewater recycling economy scales up, costs should come down. It’s already cheaper than desalination of saltwater — an International Finance Corporation estimate has found that the cost of producing potable water can be as low as $0.45 per cubic meter, while desalination typically exceeds $0.50 per cubic meter. A Framework for Direct Potable Reuse put together by water stakeholders including the WateReuse Association and the American Water Works Association also found the total estimated costs of DPR to compare favorably with the costs of other possible new sources of water.

So what does this all tell us about how we get people past that “yuck” factor? We might infer that when faced with nearly no other options, that factor simply goes away. But we don’t have to view recycling wastewater into drinking water as a last resort, either. While the intensive cleaning process isn’t cheap, it results in energy savings, environmental benefits, and water that is purer than many current drinking water sources, as noted by the California State Water Board chair. And who could reasonably argue that those are bad things?

In the end, shifting attitudes beyond the yuck factor may simply require some creativity and a massive PR campaign. Epic Cleantec, a water recycling company in San Francisco, developed a beer from recycled greywater from a city apartment building. Admittedly, greywater — the wastewater from sinks, showers, and laundry — is quite a different thing than the sewage that comes from toilets. But it’s wastewater all the same, and the company has found that people will usually try it. And it’s not the only wastewater beer that’s available, either.

But there’s far more opportunity for wastewater than just beer or even regular drinking water. In their reporting on the subject, Wired magazine posited that “the city of tomorrow will run on your toilet water” — because of the additional possibilities to extract compost and energy. Industries in the EU are already taking steps to get power, heat, and reusable chemical materials out of wastewater.

So as Wired put it, “It’s not gross. It’s science.”

FOR MORE:

• WateReuse Association
  • Recycled Water Users Network
  • National Advocacy Resources
• Framework for Direct Potable Reuse
  • Produced by the WateReuse Association, American Water Works Association, Water Environment Federation, and National Water Research Institute
• As water reuse expands, proponents battle the 'yuck' factor | KFF Health News
• California prepares to transform sewage into pure drinking water under new rules | Los Angeles Times
• Beyond the yuck factor: cities turn to ‘extreme’ water recycling | Yale Environment 360
• The city of tomorrow will run on your toilet water | WIRED
• Recycling sewage is a sensible way to improve water security – but would you swallow it? | The Conversation
• Facility Converting Wastewater into Drinking Water is Coming to the San Fernando Valley | San Fernando Sun
   
• WaterOperator.org Documents Library >> Select ‘CATEGORY’ in the dropdown, and then choose ‘Water Reuse’ to see the resources we have collected on Water Reuse.

The Potential of Artificial Intelligence in Wastewater Treatment

The need to conserve water and manage it more efficiently is perhaps now more dire than it ever has been. Among other water consumption issues: We have a record, still-growing population on the planet; accelerating levels of drought worldwide; and the artificial intelligence (AI) boom is guzzling water at a dazzling rate in order to keep data servers running.

Ironically, though, AI might just also be essential to redefining and maximizing the efficiency of our water use, along with similar emerging digital technologies like machine learning (ML), automation, and digital twins. These technologies can create “smart water” systems for industry — A concept that’s been primarily associated with drinking water, but is also starting to blossom in the wastewater sector as well.

Around two trillion gallons of treated wastewater are lost in the United States each year, which is a massive blow to US business and the environment. AI, ML, digital twins, and automation have the potential to mitigate the infrastructural inefficiencies that cause this water loss by optimizing water use, reducing the loss, and helping to build circular water management systems/economies that will emphasize reuse and minimization of use/waste across all sectors of industry.

In wastewater treatment plants specifically, these technologies can assist in understanding a system’s rate of flow, optimizing and saving energy, and providing data that is a useful tool in the decision-making process. These benefits would add up to significant cost savings in both expenditures and labor, and more importantly contribute to lessening our environmental burdens and increasing sustainability.

Wastewater Digest, which is following the expansion of AI and its sister technologies in the wastewater sector closely, says industry should implement these actions in order to reduce and optimize industrial water use:

• Assess and monitor water use with smart technology
• Invest in digital technologies like AI, ML, and digital twins
• Automate water management operations to maintain optimal performance
• Foster cultural sustainability so that everyone contributes to saving water
• Collaborate across industry to amplify results

Primary Sources and Additional Information

• Turning the tide: How automation is reshaping water use in industry
• AI is transforming the future of wastewater system management and treatment
• Wastewater, AI and aeration blower performance
• Can you trust predictive wastewater analytics?
• Exploring the intersection of data, communications & power infrastructure
• Optimizing wastewater treatment through artificial intelligence: recent advances and future prospects
• Artificial Intelligence and IoT in Wastewater Treatment
• How AI is being used in wastewater treatment plants?

RCAP's Drop of Knowledge: Article Roundup #4

Drop of Knowledge is a monthly digital article from Rural Community Assistance Partnership (RCAP.) The articles focus on topics like wastewater, drinking water, policy, and infrastructure in rural America. It contains how-to’s, tips, and guidance from more than 300 technical assistance providers (TAPs) across the country. Some featured articles are linked below:

• Resolving Inflow and Infiltration Issues in a Growing Community
• The Beginner’s Guide to Geospatial Asset Management
• How Smoke Testing Can Help Your Small Wastewater Collection System
• Red Cliff Wastewater Treatment Plant Compliant Treatment Process
• Meeting the October 2024 Deadline: A Quick Guide for Water Utilities Struggling to Get Started with Lead Service Line Inventory Compliance
• What is the Most Important Business in Your Community?

Looking for something else? Find more articles and subscribe to A Drop of Knowledge.

Technology and Innovation in the Water Sector

Innovative water treatment technologies refer to advanced and unconventional methods explored to purify and manage water resources. These solutions often leverage cutting-edge technologies and scientific advancements to address water management challenges including emerging contaminants, water scarcity, energy efficiency, resource recovery, decarbonization, etc. These technologies are often still being researched and benchmarked through laboratory or pilot-scale studies. 

We have 364 resources (and counting) on Innovative Water Technologies in our Documents Database that provide valuable information on this topic. You can search for documents about identifying water system leaks with the help of dogs, alternative water resources as we face degrading water quality and supply, treatment options for taste-and-odor problems, approaches to drinking water technology approval, and many other useful guides that will help you to deliver safe and clean water to utility customers. 

To access the wealth of knowledge on Innovative Water Technologies within our database just select "CATEGORY" in the dropdown then choose "Innovative Water Technologies." Once you make that selection, a second dropdown will appear where you can choose "HOST," “TYPE,” or “STATE” to narrow the search even further. If you have a specific search term in mind, use the “Keyword Filter” search bar on the right side of the screen.

This is part of our A-Z for Operators series.

Most Clicked Links from the Innovations Newsletter

With growing efforts to enhance water quality and to protect public health, 2021 brought many new innovations to the water sector. From innovative PFAS treatment technologies to enhanced wastewater surveillance to track the spread of COVID-19, the following list highlights the most accessed resources featured in the Innovations for Small Systems newsletter's 2021 archive.

Small Drinking Water Systems Webinar Series
A webinar series hosted by EPA to communicate the latest information on solutions for challenges facing small drinking water systems.

EPA Cybersecurity Best Practices for the Water Sector
EPA published a webpage featuring resources to help water and wastewater utilities implement cybersecurity best practices. This new page contains various cyber resilience resources available from EPA.

Tracking SARS-CoV-2 RNA through the Wastewater Treatment Process
This paper presents data on SARS-CoV-2 RNA concentration and removal rates during the different stages of the activated sludge wastewater treatment process to better understand the fate of the virus at the different stages

EPA Drinking Water Treatability Database (TDB)
The TDB presents an overview of over 120 regulated and unregulated contaminants found in drinking water with current information on treatment processes. EPA updated the TDB on May 19 to include new references and treatment options for PFAS.

Expedited Approval of Alternative Test Procedures for the Analysis of Contaminants Under the Safe Drinking Water Act; Analysis and Sampling Procedures
On May 26, EPA approved 17 alternative testing methods for use in measuring the levels of contaminants in drinking water to determine compliance with national primary drinking water regulations.

EPA Identifies Drinking Water Contaminants for Potential Regulation
EPA announced the Draft Contaminant Candidate List 5 (CCL 5) on July 12 to include 66 individual chemicals,12 microbes, and three chemical groups – per- and polyfluoroalkyl substances (PFAS), cyanotoxins, and disinfection byproducts (DBPs).

Performance of rapid sand filter – single media to remove microplastics
This paper aims to analyze the effectiveness and mechanism of rapid sand filters (RSF) for the removal of microplastics (MPs) during drinking water treatment and analyze the effect of research variables on the performance of filter media. 

Cyanobacteria Assessment Network Application (CyAN app)
On August 3, EPA launched the CyANWeb Application, which is an easy-to-use web browser-based tool that provides access to cyanobacterial bloom satellite data for over 2,000 of the largest lakes and reservoirs in the United States.

Tap Talk: The Drinking Water in Rural America Podcast
The Private Well Class program has launched a new podcast series, Tap Talk, which highlights the unique challenges which small public water systems and many private well users experience.

18th Annual EPA Drinking Water Workshop: Small System Challenges and Solutions
This free, annual workshop, which was presented virtually in September, provided in-depth information and training on solutions and strategies for handling small drinking water system challenges. This workshop will be virtual again for 2022.

Zapping Untreated Water Gets Rid Of More Waterborne Viruses
Texas A&M University researchers published a paper in September 21, where they highlighted their research validating the effectiveness of Iron Electrocoagulation in the removal of viruses from water.

EPA Awards $6 Million in Funding to Research Human Viruses Found in Wastewater Intended for Reuse
EPA announced on October 27 that five grants have been awarded funding to research on existing and novel alternative methods to detect and monitor viruses that are excreted with feces in wastewater intended for water reuse applications. 

ASDWA Publishes New PFAS MCLs White Paper for States that are Considering or Developing PFAS Drinking Water Standards or Guidelines
ASDWA published a PFAS Maximum Contaminant Levels (MCLs) White Paper on November 5, to serve as a resource for states that are developing or considering developing PFAS drinking water MCL regulatory standards or guidelines.

EPA Announces Over $3 Million in Funding to Small Businesses to Develop Environmental Technologies
EPA announced on December 14 that 30 American small businesses will receive funding to develop novel technologies to address pressing environmental and public health problems such as domestic greywater, microplastics, and lead service lines.

Nutrient Smart Recognition Program
WEF and EPA launched the NutrientSmart (NSmart) program in December to help reduce nutrient loadings in waterways by encouraging the adoption of enhanced nutrient management practices by water utilities and distributing information on tools and methods for lowering nutrients.

Fifth Unregulated Contaminant Monitoring Rule
EPA published the fifth Unregulated Contaminant Monitoring Rule (UCMR 5) on December 27 to better understand the national occurrences and levels of 29 PFAS found in the nation's drinking water systems.

Check out past issues of the Innovations newsletter.

The Benefits of Drones in the Water Industry

Unmanned aircraft systems (UAS), also known as drones, have slowly made their way into various parts of society, including the water sector. They offer a more accessible and affordable way for water utility managers to survey their systems. They also offer plant managers the ability to collect detailed information about the status of their utility through aerial photos and videos. 

The greatest benefits of drones are that they are highly efficient while still being relatively inexpensive. Drones can be used to collect data ranging from updating processes to designing additions, as well as building changes, maintenance, and demolition. 

Some water companies in France are even using drones to inspect sewer operations. They are also being used in New Zealand as part of a water quality monitoring project. Drones are being used in Ireland to survey problems before they arise and catch unlawful dumping that would eventually become issues for wastewater treatment workers to handle. Drones have proven to be especially helpful in the wastewater industry by increasing worker safety, reducing energy consumption, streamlining planning, improving insight and education, and efficiently collecting samples.

Using Willow Trees to Treat Wastewater

This article was featured in a recent edition of Innovations for Small Systems, our monthly water technology newsletter.

Researchers at University of Montreal, Canada have found a way to filter the waste from municipal wastewater through the roots of willow trees while also producing renewable bioenergy and 'green' chemicals. The study, which was published in Science of the Total Environment, details the experiment conducted in Quebec, Canada to investigate the potential for sustainable wastewater treatment through phytofiltration, an emerging method to remove contaminants from water through the use of plants, to be integrated with renewable biorefinery. 

Phytofiltration plantation is an alternative wastewater treatment method where root systems from non-food crops, such as fast-growing trees, are used to capture contaminants and nutrients from wastewater. Short rotation coppice (SRC) willow has been considered as a promising renewable bioenergy crop due to its natural tolerance to contamination and the roots ability to filter out nitrogen in sewage, which can then be harvested for renewable lignocellulosic biofuels. This concept of a biorefinery illustrate the potential of multifunctional biotechnologies to address environmental challenges caused by human activities.

Photo Credit: Katy Walters

Featured Video: Why Are 96,000,000 Black Balls on This Reservoir?

By Jill Wallitschek

In 2015 the Los Angeles Department of Water and Power went viral when it unleashed 96 million shade balls into the Los Angeles Reservoir. The 175 acre reservoir served to store 3.3 billion gallons of treated drinking water. Shade balls were previously introduced to three other reservoirs in the LA area between 2008 and 2012. Releasing the 96 million balls marked the end of a 8 year project.

The project was first instigated when the Department of Water and Power was notified of high bromate levels in their water. Bromate (BrO₃^- ) is a disinfection byproduct regulated at 0.01 mg/L. High levels can increase risk of cancer. The chemical forms when bromide (Br ^- ), an otherwise harmless ion, reacts with ozone (O₃). For this reason treatment plants that use ozone are required to monitor for bromate monthly. Qualifying plants can reduce their monitoring to quarterly.

The LA Department of Water and Power determined that while they were finding low levels at the treatment facility, levels were elevated at the reservoirs. Upon investigation the facility realized that bromate can form under chlorination as well. When chlorinated water containing bromide reacts with sunlight, it forms bromate at even higher concentrations than ozonation. This realization prompted the facility to look toward a solution.

Removing the naturally occurring bromide wasn’t an option. Chlorination residual was necessary to protect public health. Ultimately the Department determined that sunlight was the only variable left to control.

After brainstorming for affordable and effective covers that could block sunlight across 175 acres, the Department discovered a product called “bird balls”. At the time, bird balls were used to deter waterfowl from swimming in contaminated water bodies or ponds near airport runways. These balls were made from high density polyethylene, a floatable, food grade plastic. The addition of carbon black gives them a black color and increases their life expectancy to approximately 10 years without sun bleaching. After consulting the manufacture, the balls were put through a small-scale test to access their bromate reduction abilites. The shade balls passed with flying colors.

Shade balls not only reduce bromate formation in the reservoir, but they deter birds, control algae, and reduce evaporation by 80 to 90%. Having been implemented under historical drought conditions, the innovation was applauded for its water saving results. According to the Massachusetts Institute of Technology these shade balls will have to be used for roughly 2.5 years to compensate for the water required to produce them. Since less chlorine is required to control algae formation with the adoption of shade balls, the treatment facility is experiencing significant cost savings as well. Over the course of their life span the reduction in chlorine use and evaporation will have paid for roughly half the shade balls.

Shortly after their installation, one of the reservoirs was removed from service and two of the remaining reservoirs transitioned to floating covers. Federal law requires that all drinking water bodies open to the air be covered. Transitioning the final Los Angeles Reservoir would have been too cost prohibitive based on its size. So given the effectiveness of the shade balls in such a large area, they shall remain in the Los Angeles Reservoir to prevent bromate formation, evaporation, and algae for the Los Angeles people.

What's on the Drinking Water Radar for the Year Ahead: 2019

Being a small-town water operator is not easy; it is up to you to ensure the quality of your community's water day-in and day-out, often with very limited resources. Let WaterOperator.org help you meet the challenge head-on with this list of tools and resources to put on your radar for the year ahead:

• Have you gotten in the groove yet with the new RTCR requirements? Here are two new documents from the USEPA designed to help small public water systems: Revised Total Coliform Rule Placards and a Revised Total Coliform Rule Sample Siting Plan with Template Manual. Additional compliance help, including public notification templates, a RTCR rule guide, a corrective actions guidance and more can be found here.
• While we know your hands are full just getting the job done, there are new and emerging issues you may have to deal with in the year ahead. For example, this past year many communities have been dealing with PFAS contamination issues. This ITRC website provides PFAS fact sheets that are regularly being updated on PFAS regulations, guidance, advisories and remediation methods. Especially of interest is this excel file that has begun to list the different state standards and guidance values for PFAS in drinking water as they are developed. Be sure to check back often for updates.
• Your utility may also have to adjust to new compliance rules in the coming year. In Michigan, for example, a new Lead and Copper Rule arising from the water crisis in Flint has gone into effect, making it the strictest in the nation. Other states, such as Ohio, have also adopted tougher standards, or are now requiring schools to test for lead. Oregon has established temporary rules that will require drinking water systems in the state using certain surface water sources to routinely test for cyanotoxins and notify the public about the test results.
• With a warming climate, these incidences of harmful algal blooms in surface water are on the increase, causing all sorts of challenges for water systems that now have to treat this contaminant. This cyanotoxin management template from the EPA can help assist you with a plan specific to your location.
• Worker turnover and retirements will still be an issue in 2019. According to this article, the median age for water workers in general (42.8 years) and water treatment operators specifically (46.4 years) are both above the national average across all occupations (42.2 years). You can keep transitions as smooth as possible by using EPA's Knowledge Retention Tool Spreadsheet and/or this Electronic Preventive Maintenance Log.
• New Tech Solutions: A UMass lab focusing on affordable water treatment technologies for small systems will be rolling out its Mobile Water Innovation Laboratory in 2019 for on-site testing. In addition, the facility is testing approaches to help communities address water-quality issues in affordable ways. "Early next year, in the maiden voyage of the mobile water treatment lab, UMass engineer David Reckhow plans to test ferrate, an ion of iron, as a replacement for several water treatments steps in the small town of Gloucester, MA.

But even without all these challenges and new ideas for the future, simply achieving compliance on a day-to-day basis can be tricky - if this sounds familiar, you may want to check out our recent video on how operators can approach the most common drinking water compliance issues.

Featured Video: The Future of Water

Water is a scarce resource for many communities around the globe, and this scarcity is becoming more and more widespread. Our featured video this week from Quartz Media looks out how one locality half a world away has addressed this challenge, and how the rest of us can learn from systems like these where the "future of water" has already arrived.

While this video focuses on a larger metropolitan area, there are some interesting takeaways for smaller systems as well such as:

•  Solutions to water challenges are best solved at the individual and/or community level. 
•  Water reuse is most likely already happening in your community and efforts can be made to change public perceptions. For example, a wastewater pipe enters the Mississippi River every 8 miles - meaning almost every community using the river as a water source is already drinking someone else's wastewater!