Wastewater Recycling

What is Wastewater Recycling?

If you’ve ever gone camping or traveled off-grid, you may already be familiar with some of the most tried-and-true DIY ways to purify water. You’ve got a few options: boiling, running through filtration, using a charcoal stick. Each method basically does the same thing—take water that’s potentially unclean and make it safe to use and even drink. 

 

Now imagine doing that on a massive scale—not just for a campsite or a few bottles, but for an entire city. That’s the main idea behind municipal wastewater recycling: taking the water we already have—everything from shower runoff to toilet water—and purifying it until it’s clean enough to be reused. 

 

With climate change causing dwindling water supplies across the globe—especially in the American Southwest—ensuring a clean, safe, and sustainable water supply has never been more critical. 

 

Wastewater recycling offers a powerful solution. By treating and reusing what we’re currently just throwing away into the ocean, we can build a more reliable and sustainable water supply—and finally make Los Angeles drought-proof for good. 

How Wastewater Recycling Works

At its core, wastewater recycling works by using technology to speed up the natural processes that clean water in natural ecosystems.  

Though exact systems may vary from plant to plant, here’s how it generally works: 

 

  • Primary Treatment: The process begins with physically removing large debris and solid waste from the water through filtering and settling. 

  • Secondary Treatment: Next, carefully introduced microorganisms break down organic matter in the water. These biological processes are essential for removing harmful organic pollutants and ensuring the water is ready for further treatment. 

  • Tertiary Treatment: The water is then put through more advanced treatment to remove even the smallest contaminants: 

  • Membrane Filtration: Ultra-thin filters remove microscopic particles, pathogens, heavy metals, and chemicals via processes like reverse osmosis.  

  • Disinfection: Methods like UV light or chlorine kill any remaining bacteria and viruses. 

  • Advanced Oxidation: Additional chemicals break down pharmaceuticals and other trace pollutants into harmless components. 

  • Final Distribution: After these multiple treatments, the water is finally clean enough for its intended uses—whether that’s watering crops or cooling industrial systems (known as non-potable reuse) or being sent for additional processing to be safe enough for drinking (or potable reuse). 

 

These advanced wastewater recycling technologies, honed over decades of innovation and rigorous testing, blend the best of microbiology, chemistry, and engineering to produce water that is not only consistently safe but also exceptionally reliable.  

 

Why Wastewater Recycling Matters

LA County’s water infrastructure currently relies on a “two straws and a bathtub” system – pulling imported water from hundreds of miles away in the Owens Valley and Colorado River (the “straws”), as well as local groundwater (the “bathtub”). But as climate change dries up these historical resources, it’s more important than ever to come up with creative approaches to develop new and sustainable water supplies. 

Moreover, although both LA City and County have already invested in wastewater recycling and treatment plants, nearly 600 million gallons of treated water still gets discharged into inland and coastal waters everyday instead of being added to our water supply! 

If instead we made the necessary investments to expand wastewater recycling infrastructure—and treated recycled water as a valuable resource rather than wasting it—we could usher in a more sustainable, drought-resistant future for Los Angeles. 

Addressing the “Ick” Factor

Despite the wastewater recycling’s technological success, public perception remains one of the greatest challenges to widespread adoption.  

It’s worth remembering, first of all, that all water on Earth is recycled. Through the natural water cycle, water evaporates, condenses, and falls as rain, mixing with countless substances along the way that need to be filtered out to be safe for human consumption. Wastewater recycling mirrors this process but does so with advanced technology and rigorous controls, including continuous testing to ensure safety and quality at every step. 

 

In fact, regulations for purifying wastewater are often more stringent than regulations for traditional water and wastewater treatment plants. As such, purifying wastewater can do a much better job of keeping forever chemicals (i.e., PFAS) and other emerging contaminants like pharmaceuticals out of our drinking water and local waterways.  

 

In addition, places like Orange County and Singapore have used recycled water in their drinking supply for decades, proving the process is not safe but also effective in addressing water scarcity. 

What Is Being Done About The Issue

The good news is that local agencies, decision-makers, and nonprofits like LA Waterkeeper have been pushing to modernize our water systems and invest in wastewater recycling for a while now.

Big Commitments to Recycling

In 2019, then-Mayor Eric Garcetti announced a bold goal: by 2035, Los Angeles will recycle 100% of its wastewater. Through a partnership between LA Sanitation (LASAN) and the LA Department of Water and Power (LADWP) called Pure Water Los Angeles, the city plans to produce 230 million gallons of recycled water per day to support the transition from importing 90% of its water from outside the region to increasing local water supply to 70%. 

 

The Metropolitan Water District of Southern California (MWD), which was founded and has historically focused on importing water, is also getting on board. They’re teaming up with the LA County Sanitation Districts (LACSD) on Pure Water Southern California. This effort aims to reclaim 150 million gallons of wastewater daily. Together, these two projects would create the largest water recycling programs in the world. When combined with smaller local efforts, like Pure Water Las Virgenes-Triunfo, Ed C Little Water Recycling Facility, and the Donald C Tillman Water Reclamation Plant, they could meet 35–40% of LA’s water needs—all from recycled wastewater. 

What Challenges Still Exist

While wastewater recycling offers significant benefits, there are key considerations to address to ensure its successful implementation. 

 

Earlier this year, LA Waterkeeper and the UCLA Luskin Center for Innovation worked with experts to develop strategies for optimizing and integrating recycling projects in the LA region. Our aim was to provide guidance to ensure such projects are implemented quickly and efficiently while minimizing costs and avoiding negative impacts on communities and the environment. 

 

Here are some of the key challenges we identified: 

 

  • Ensuring Affordability - As the region invests in major infrastructure upgrades, it’s vital to ensure water rates remain affordable for households. Agencies must coordinate to secure local, state and federal project financing that doesn’t place an undue financial burden on residents—particularly low-income households already struggling with high costs of living. 

  • Minimizing Negative Impacts - Agencies must also prioritize minimizing impacts on communities and the environment. A coordinated, regional approach between water, wastewater, and groundwater agencies can streamline water purification infrastructure, reducing the need for extensive piping and pumping. This not only lowers costs but also decreases the carbon footprint and minimizes disruptions to communities and ecosystems. 

  • Building Public Trust - Public perception is one of the biggest hurdles for wastewater recycling. Overcoming the so-called "ick factor" requires a strong, collaborative communication strategy. This means crafting a clear and compelling narrative about the benefits of a secure water supply, tailoring messages to meet the needs of diverse communities, and enlisting trusted voices to lead the conversation. 

  • Coordinated Monitoring - Although recycling technologies have been proven safe, public health remains the highest priority. To ensure water quality meets the strictest standards—for both public and ecological health—a coordinated monitoring plan is essential. Continuous testing and transparent reporting are critical for building trust and confidence in recycled water. 

  • Advancing Conservation - While water recycling is a vital part of the solution, it cannot address the region’s water challenges on its own. To create a truly sustainable system, recycling must be paired with smarter water use, such as adopting drought-tolerant landscaping, installing low-flow appliances, and implementing community-wide water-saving initiatives. Without these efforts, simply increasing capacity could inadvertently exacerbate the water crisis by encouraging overuse. 

 

Building on these efforts, LA Waterkeeper is also actively working to advance smart wastewater recycling. Our initiatives include advocating for strong state standards alongside the California Coastkeeper Alliance, urging agencies to advance purification projects, and securing hundreds of millions in state and federal funding for initiatives like Pure Water Los Angeles and Pure Water Southern California. Additionally, we support research and convenings to ensure these projects are implemented efficiently while minimizing costs and environmental and community impacts. 

So, What Can I Do to Help Advance Wastewater Recycling Efforts in Los Angeles?

If you’re inspired by the potential of wastewater recycling to secure Los Angeles’ water future, there are several ways you can personally contribute to advancing these efforts: 

  • Stop Flushing Wipes and Other Non-Flushables 

Protecting wastewater systems starts at home. Despite being labeled as such, “flushable” wipes are not designed to break down like toilet paper. Their durable fibers mean they don’t disintegrate in water, leading to clogs in pipes and sewer systems.  

Even if wipes make it to the treatment plant, they can jam and damage filtering machines, slowing down the recycling process and increasing maintenance costs. Keeping wipes out of the system ensures treatment plants can run efficiently, preventing unnecessary delays and expenses that could hinder water recycling efforts. 

  • Educate Yourself and Others 

Take the time to learn about how wastewater recycling works and share this knowledge with friends and family. Public support is crucial for overcoming the "ick factor" and building trust in this essential technology.  

Watch this video for an in-depth look at how wastewater recycling works. Understanding the process can make it easier to explain its benefits to others and advocate for its adoption. 

  • Engage in Community Advocacy 

Support policies and projects that promote wastewater recycling, such as Pure Water Los Angeles and Pure Water Southern California. Attend public meetings, write to local officials, or join advocacy campaigns led by organizations like LA Waterkeeper. 

  • Conserve Water in Your Daily Life 

Pair your support for wastewater recycling with smart water use at home. Adopt drought-tolerant landscaping, fix leaks promptly, and use water-efficient appliances to ensure that recycled water is part of a broader conservation strategy. 

  • Support Organizations Leading the Way 

Nonprofits like LA Waterkeeper play a critical role in advancing wastewater recycling projects, promoting public education, and ensuring equity in water management. Consider donating, volunteering, or amplifying our work through your networks. 

 

By taking these actions, you can play an important role in helping Los Angeles embrace wastewater recycling as a cornerstone of its water future. Together, we can ensure a more sustainable, resilient, and water-secure city for everyone.