I am at the Florida Section of American Water Works Association’s Fall conference. A major topic of interest is potable reuse – i.e. drinking wastewater. Before you say yuck, read on….
Potable reuse remains a topic among those in the water industry. Let’s be clear -the technology to treat wastewater for drinking purposes exists and in fact is practiced in the US today (Big Springs Texas as a direct potable reuse project, Orange County CA as an indirect potable reuse project, among others). Several test programs have been conducted in southeast Florida. A couple have been successful at meeting the drinking water quality goals, including one I was a part of. Ours required a demonstration of 99.9% removal of emerging contaminants, that we demonstrated by spiking at 1000 times the detection limits. It worked. Central Florida has 4 projects being investigated and Texas has a couple more. Potable reuse is coming to Texas, California, Florida and Texas. Other water limited areas (Colorado, Arizona, New Mexico, and perhaps the Carolinas and Georgia) are not that far behind.
Fast forward and the WateReuse Association has completed a series of studies on the issues, including labeling of water uses and addressing the realm issues with potable reuse, – monitoring and public perception. I would argue that the way the industry is set up today, piping wastewater treated with reverse osmosis, peroxide and UV light to a water treatment plant as raw water (it is incredibly pure), can be successfully modeled. Most RO and UV systems use program logic controllers and sensors to monitor conditions. Protocols for the sensor reading need to be written but agreement can be reached on this matter. Those protocols are part of ongoing discussions in Florida, Texas and California at present and from a regulatory perspective should be able to be implemented.
That leaves public perception. While terms matter (toilet-to-tap is not helpful, nor is highly treated wastewater), the reality is that all raw water is arguably someone’s treated wastewater. 85% of all wastewater is returned, some by permit requirement, to nearby rivers and streams – often the same ones the water supplies came from. Hence the City of Raleigh pulls water from the Neuse River, then discharges downstream toe the same river. Smithfield, Goldsboro and others downstream of the Neuse do exactly the same thing. Wastewater is treated before discharge, and the downstream water supply is treated before distribution. The Mississippi is the same way. So the reality is that we need to show people that potable reuse is likely safer and more reliable from a water quality perspective than surface waters. Potable reuse will have no turbidity that interferes with disinfection, no of limited temperature variations, no algae, no protozoas, not emerging contaminants, no viruses and no bacteria to speak of, as compared with even high quality surface waters, which have all of these things. Water utilities provide quality drinking water 24/7 and have since the widespread adoption of filtration and disinfection over 100m years ago. This is because the treatment processes work, and because for over 100 years the water utilities have monitored water quality and the number of potable water system related diseases is tiny (and if the occur are usually a result of piping or storage issues as opposed to treatment issues). So time for a paradigm shift. Draw a picture – you want river water with who knows what in it, or reverse osmosis, UV treated wastewater of known and consistent quality, monitored even more often than the river? Draw that picture. And remember, fish poop in the river.
Now about that Disani water……..