What Is Water Recycling?
The Circular Economy, Part 1/4: GreenBiz's "State of the Green Business 2017" recently addressed the effect expanding cities and changing seasons have on our environment's water supply. And with water outranking food shortages and cyberattacks as global crises, according to the World Economic Forum, it's time to talk about it: What does it mean for a community to effectively "recycle" the flow of clean water? How do new types of circular infrastructure now repurpose water beyond the potable?
How Growing Cities Are Expanding Their Use of Water
Last year, the World Economic Forum issued a global risk report prioritizing water crises over cyberattacks, financial instability and food shortages as the global economy's most important issues. That's right — a citizen's computer, bank account and pantry, while important, take a back seat to his/her tap.
Clean water is very reflective of the civil and climatological changes facing cities today. The idea of recycling water is therefore a major point of interest around our infrastructure. But well-planned water recycling practices have a lot to do with how we think recycled water can be used.
Myth: Drink or Bust
It’s easy to grade water on its benefit to the (human) end-user, but this is a dangerous lens through which to view a natural resource because it focuses on just two options: Either you can drink it or you can’t.
Water recycling infrastructures rethink the possibilities of how non-drinkable (non-potable) water can be used. Much like plastic, which consists of seven categories defining its recyclability, water can be repurposed differently depending on its quality. The highest grade is drinkable and can be added to groundwater networks, but lower grades have an important role to other water-dependent industries.
According to GreenBiz's State of the Green Business 2017, rising populations and temperatures are the main challenges to the availability of drinkable water. As living areas expand, so must municipal water systems. When seasons get drier, so do many aquifers. Encouraging the public to shorten their showers and flush the toilet less can help with water conservation, but not necessarily enough to combat its diminishing supply in the environment.
Water recycling systems have gained momentum as cities begin to take a comprehensive look at where and why they discard certain types of water in the first place. By recognizing the symbiotic relationship between utility systems, the community can make water an object of the circular economy, where it’s used not as a one-and-done commodity but as a vehicle that does laps through a variety of operations.
Recycled Water in Use
The idea behind water recycling is that its value exists in a spectrum of uses, all the way to the industrial level. To prevent processed sewage that isn't treated to drinking standards from being wasted, cities like Honolulu are now reclaiming and recycling effluent that still complies with many non-drinking needs, such as irrigation, landscaping and the like.
Its water recycling facility, run by the Honolulu Board of Water Supply, can produce 12 million gallons of reusable water per day, potentially saving the community $35 million over 20 years in what would be additional water distribution sites. This infrastructure allows the surrounding community to grow without lacking in potable water.
Water recycling projects allow cities to endure shortages brought on by changing climates because the water being used is always available. And by dedicating this non-drinkable supply to industries that can use it, the community has more clean water available for public consumption.
Read Part 2 of this series here.
Catherine Soriano | Assistant Project Manager, Honouliuli Water Recycling Facility, Veolia North America