The idea of water reuse is nothing new. Various industries, municipalities and even some businesses have been doing it for years. But lack of education about the technologies available, potential benefits and the quality of reused water keeps many residential and commercial consumers from being open to water reuse systems.
“There is a number of market studies that show water reuse has seen limited adoption. I would estimate that significantly less than 10 percent of all wastewater is currently reused in a meaningful way,” says Tim Davis, marketing coordinator at Pinnacle Ozone Solutions LLC.
“I think in terms of commercial there is a much deeper saturation, but there is still lots of room for growth,” agrees Marianne Metzger, vice president of sales and marketing at Certified National Analytic Labs (CNA). “In terms of residential, I think this is rather new and as people become more aware about the need for water conservation, which includes reuse as well as reduction, I believe the residential market is poised for growth over the next couple of years.”
It falls to the dealers who already have established relationships with residential and commercial customers to educate them on the water reuse options available and why they are important to consider as we move into a future of smart water use.
Why water reuse?
Water reuse is more important now than ever, as developing countries that have an abundance of available water still have thousands with no access to potable water and developed nations like the U.S. and Australia face unprecedented water shortages from debilitating droughts. And, with growing populations everywhere come increased industry and irrigation demands, with water supplies that can’t keep up.
“The need for water reuse is not based on any overall shortage of worldwide water since the Earth constantly recycles water through evaporation and condensation. Rather, the primary need to reuse water is to preserve and extend the sources of naturally occurring fresh water,” says Shea Casey, managing director at VaraCorp. “By capturing and reusing water, particularly where fresh water is scarce, we can lessen the demand on fresh water supplies.”
Water shortages are often not questions of quantity, but of quality. When a water supply is overdrawn, contaminants become more potent, a problem affecting thousands in California at the moment.
While it is easier to sell the benefits of water reuse to those actually living in areas affected by drought and climate change, it is important to remind those in more water abundant areas that potable, quality water is not an unlimited, low cost resource.
Davis explains the financial sense of wastewater treatment: “Perhaps the most practical reason for reuse is better use of economic resources. By the time water leaves most wastewater treatment plants, it is often of equal or higher quality than many raw water supplies. In practice, there isn’t that much more treatment required for achieving a nearly potable water quality standard. Since the plant already has this water source, it does need to pump or capture the water before final treatment. In short, the overall cost to capture, pump, treat and discharge or distribute water for reuse is often less expensive and requires less work than building a new water treatment plant of similar capacity.”
Stormwater is another readily available water source that will not draw on the fresh water supply but can be used by anyone.
“Capturing stormwater runoff from your roof and re-using it within your home helps everyone. It helps a utility that may be overburdened by excessive rain and it gives the homeowner water to use in home, so this saves on water and sewer bills,” Metzger says.
The “yuck” factor
Many customers already know and understand the reasons for water reuse, even if they don’t actively seek out the technologies for their own use. For many, despite understanding the need, the idea of reusing wastewater is too foreign.
“The single biggest factor limiting reuse is the 'yuck' factor,” asserts Davis. “Many people fail to realize that all water on our Earth is, in fact, reused. There is only a limited amount of water on our planet and it is continually going through a natural cycle. By using [appropriate reuse] technology to treat and reuse wastewater, we are actually making better use of water, energy, talent and financial resources toward building a sustainable economy and ecosystem.”
One of the reasons customers are hesitant is because many think of water reuse as toilet to tap, according to Metzger. "There are less severe options of reusing water that is used in washing such as [for] bathing, washing machines, dishwater and other sink water, for irrigation or to flush toilets. Dealers just need to educate people about the various options,” she adds.
Another possible drawback for many customers is the high cost of the investment in water reuse technologies. Again, the key is educating the customer on the long-term money savings and benefit to the fresh water supply and weighing that against the higher initial cost of these products.
“Everyone claims to want to go green,” says Casey. “Yet, if they have to pay a higher price for a green product, they usually balk. So, the key is to have an answer for the question about the expected savings of water reuse systems."
And these savings can be significant, according to Metzger, especially considering that water rates are likely to continue to rise across the country. Large manufacturers have been adopting water reuse technologies for some time now considering this trend, finding it a more cost effective option.
“In most cases the marginal cost of treating wastewater to reuse standards is somewhat significantly less than the cost to purchase an equivalent volume of potable water,” explains Davis. “Since the water is already at the site, the costs of further pumping is not a great factor. Perhaps most importantly, sites with restricted potable water supplies can potentially double their available water supply in a reuse scenario.”
Achieving water reuse
If you succeed in convincing a customer that water reuse is necessary, safe and cost effective, they’ll likely have questions about how water reuse can be achieved in their home or business.
Residential water reuse technologies are the most challenging, as they need to be simple to operate and consumers need to fully understand the appropriate uses for various types of wastewater and the different contaminants that could be present.
“Most residential customers don’t have the required technical background to operate a wastewater reuse system to produce safe, high quality effluent,” says Davis.
For this reason, most water reuse systems for residential use produce water that is recommended for applications other than drinking water, like irrigation or flushing toilets.
According to Metzger and Casey, residential water reuse technologies include:
- Greywater systems: Take water used for bathing or washing and re-direct it to be used to flush toilets or for irrigation.
- High efficiency RO systems: Waste little, if any, water due to a reuse process.
- Rainwater collection systems: Capture rainwater for household uses such as taking showers, washing cars or watering household plants.
“With a little forethought a family could recycle water several times before it is ultimately disposed,” notes Casey.
There are more opportunities for water reuse in the commercial sector, especially in businesses that produce a large amount of wastewater like carwashes or those that use water for irrigation like golf courses.
“Almost all existing treatment technologies are applicable to commercial (and municipal/industrial) scale water reuse,” says Davis, and according to Metzger “more and more companies are making efforts to treat and reuse water within their processes, especially those that use large amounts of water.”
According to Davis, the following technologies should be kept in mind for commercial water reuse:
- Membrane filtration (MF/UF): For pathogen and particulate removal.
- Reverse osmosis (RO): For salt and mineral removal.
- Ozone: For advanced disinfection and trace organics/pharmaceuticals removal.
- Activated carbon (GAC): For effluent polishing.
“When combined with a conventional biological treatment process, these technologies can easily produce potable quality water from most any waste stream,” Davis says.
“The power of dissolved oxygen is too often overlooked in commercial and industrial operations,” asserts Casey. “Dairy farmers in the Midwest, for example, are waking up to the fact that if they aerate their wastewater lagoons, they can convert cattle waste into ‘compost tea.’ This highly oxygenated water not only destroys the high odor of the manure, but it ramps up beneficial aerobes. These aerobes help turn the solid wastes into nutrient-dense liquids. The resultant tea can now be used to irrigate local crops which serve as a food source for the dairy herd.”
The dissolved oxygen can also eliminate the odor of wastewater so it can be used for municipal and commercial irrigation of public places like golf courses, Casey explains.
While there are many ways to reuse water in municipal and industrial applications, the commercial and residential technologies should not be overlooked.
As Metzger summarizes, “Let’s not forget that in addition to cost savings, water conversation is helps us become more sustainable.”