From what we use to build and power our homes to how we cultivate food, people globally are searching for a sustainable response to rapid social and economic growth. But what if I told you there’s a less discussed sustainable solution picking up steam? Be warned that this one might have a bit of a “yuck factor,” but, if overcome, could revolutionize our daily lives and resolve water scarcity. I’m talking about wastewater reuse. Sounds gross, right? Except it isn’t, and we have the ability to treat wastewater effluent to the same high-quality standards we use for our everyday water. In fact, wastewater can be so clean that it can be used to brew beer. While it may not be at the forefront of discussion in the northeastern region of the country, when talking on a larger scale—like nationally or globally—it has the potential to solve the threat of water scarcity. Beyond the most basic form, which is its indirect potable application, wastewater reuse can be used at either a residential or industrial scale, and also can be used for lawn and land irrigation. Indirect potable reuse is currently in place in many of the country’s municipal water systems and goes as follows: wastewater is treated to remove pollutants and released into local bodies of water. Once that effluent is released and mixed with the local water bodies, the water is pumped out to a municipal water supply and distributed to its customers. However, there are instances where the middle step that releases treated effluent into local bodies of water is skipped.
That’s what’s called direct potable reuse, and, although it’s much less common, it could be part of a solution in response to the recent droughts that have riddled arid regions of the country. Industrial reuse is one of the more prevalent forms of wastewater reuse in large-sale operations. Because industry accounts for nearly half of our total water demand, you’ll see many large operations implement their own private treatment plants. This avoids tapping into the municipal water supply to meet their operational needs, like cooling and washing. On a residential scale, there are various routes to take that are largely predicated on local circumstances—for instance, if an area typically requires septic tanks, people in that area could incorporate their own wastewater treatment system. There is also the option to avoid reusing wastewater as whole, and instead use the water from daily tasks like laundry, showering and washing dishes. In this form, the reused water is called greywater, and can be used for laundry, toilets and irrigation. What may be the common model for wastewater reuse, lawn and land irrigation don’t have to necessarily meet potable or residential water requirements.
One of our current projects, which is the first of its kind for the respective county, involves hooking up a golf course’s watering system to its neighboring wastewater treatment plant. Methods such as these provide reusable, treated water that doesn’t tax the surrounding ecosystem. While this sounds great on paper, the fact of the matter is wastewater reuse is expensive. These systems require a high degree of treatment, their own piping distribution, and there are seasonal fluctuations in demand. Unfortunately, water scarcity is a harsh reality for many, not just nationally but across the globe. As the technology behind these methods inevitably advances and costs to install these systems drop, more municipalities will likely see the need to invest in our future. The success in implementing these systems on a large scale has set a foundation. All that’s left for us now is to progress. Chris Weiss, P.E. is the Treatment Systems Department Manager for H2M's wastewater division. For more information, you can contact Chris as firstname.lastname@example.org.