DES PLAINES, ILL. — Water reuse will become increasingly necessary. It’s necessary now, such as in Orange County, Calif., where they are using reclaimed water to recharge the aquifer to prevent Pacific Ocean salt water from leaching into the drinking water supply. It will become increasingly necessary in any place in the U.S. that is experiencing drought. The details on how to reuse water, however, are confusing and sometimes contentious.
The issues need to be clarified as the International Standards Organization works on developing global water reuse standards. Chances are excellent that U.S. experts will influence the way water is reused around the world. The American Society of Plumbing Engineers is running the ISO’s TC 282 on water reuse. It was with that in mind that Jim Kendzel, executive director/CEO of ASPE assembled some of the best minds in the plumbing, water utility and water quality industries here in late June to pick their brains in advance of the next ISO meeting in November in Tel Aviv, Israel.
The Water Reuse Workshop was co-sponsored by ASPE, the National Sanitation Foundation and the Water Quality Association, and featured speakers from the American Rainwater Catchment Systems Association, International Association of Plumbing & Mechanical Officials, International Code Council, NSF, U.S. Green Building Council, American Society of Drinking Water Administrators, and a number of others.
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Water can be safely reused, pointed out David Crawford, the president of ARCSA and the president of manufacturer Rainwater Management Solutions, if it is suitable in quality for the application. Drinking water and water suitable for underground drip irrigation are completely different in quality. Many of the details in between are in dispute and many of the definitions are not consistent.
For example, graywater is drain water from lavatories, showers and laundries. But if you filter and treat graywater onsite, is it still graywater or has it turned into onsite treated non-potable water? USGBC will give a project LEED points for reusing RO discharge water, but IAPMO and ICC won’t allow it in their plumbing codes. There’s stormwater, rainwater, graywater, black water, condensate drain water, and foundation drain water, all with varying amounts of contaminants, varying treatment requirements and differing appropriate uses.
Water quality rules have been around for a long time because of typhus outbreaks and, paradoxically, a short time now that we can measure arsenic or heavy metals down to parts per trillion.
Fifty years from now people will have plenty of water, although it will be all recycled sewage, said the seminar’s keynoter, Dr. Joseph Cotruvo, the former director of EPA’s Drinking Water Standards division, and now a vice president at NSF who’s involved in the World Health Organization.
“The whole idea of direct-to-potable reuse is about not putting it into the ground first,” Cotruvo said. “Lots of drinking water people are thinking about it now and it’s good that ISO is thinking about it too.”
The technology is here now, he said, plus you can extract not just water but energy, biofuels and fertilizer out of sewage. We’ve been recycling sewage since man walked the earth — somebody always lived downstream. Before the 1970s most sewage was dumped in the river. After the Clean Water Act was passed, sewage was treated before it was dumped in the river and the quality of rivers went up. Sometimes it is allowed to percolate through the soil into the aquifer and the water is treated by a water utility for “finishing” before it goes into the mains.
In 1980, EPA created a protocol for water reuse, leading to microbiology and toxicology testing. EPA also came up with a list of industrial pollutants for which factories had to pretreat because the sewage treatment plans weren’t capable of handling them. The Safe Drinking Water Act changed the game from filter it and drink it to measuring everything that’s in the water such as fecal coliform, cryptosporidium or giardia lamblia. Gas chromatography and water chemistry are so much more sophisticated now, as is our ability to treat water with RO membranes, ozone and activated carbon. The astronauts on the space station are drinking filtered and treated urine.
So we can treat and reuse water, but the how is still open to question because the field is young. The Australians have water reuse guidelines. The EPA issued guidelines in 2012. The Water Reuse Association will begin developing consensus guidelines for indirect potable reuse and direct potable reuse. The World Health Organization just started work on the topic in June 2014. Many states are working on reuse, such as California, Texas and Arizona. And when Kendzel goes to the ISO meeting in Tel Aviv, it will be just the second meeting of the committee.
Texas has been a leader. ARCSA was founded in Austin in 1994, noted E.W. “Bob” Boulware, P.E., a past president of ARCSA and president of Design-Aire Engineering, Indianapolis. ARCSA took the best ideas from Germany, Australia, Hawaii and Texas, and wrote Rainwater Catchment Design and Installation Standards, which caught the attention of both IAPMO and ICC. Boulware sat on the code committees of both bodies as they developed their respective green plumbing and mechanical codes. The rainwater standard, ARCSA-ASPE Standard 63-2013, is now an international standard.
Then there are standards for the machines. NSF Standard 350 is the voluntary consensus standard for onsite wastewater recycling and reuse treatment systems for non-potable applications, explained Tom Bruursema, general manager of NSF Sustainability. Standard 350 is for residential and commercial water reuse using graywater. Standard 350-1 is a lesser quality standard for graywater and combined wastewater for non-potable effluent uses for toilet and urinal flushing or for outdoor surface and subsurface irrigation.
The devices process up to 1,500 gallons per day, Bruursema said. The systems are tested with actual graywater and were also tested with synthetic graywater. (There’s a cocktail for artificial graywater that the Australians came up with.) The test runs for six months. It’s a lengthy evaluation operated in accordance with the manufacturer’s instructions. NSF collects a lot of samples and creates a lengthy report for what’s coming out of the device. NSF gathered everything they could find on water quality criteria from EPA, WHO, the Australians and the Japanese and developed allowable water quality criteria for turbidity, E. Coli, pH, chlorine, and total suspended solids.
While the means and methods exist for reusing water, regulators are skeptical about whether the systems will be maintained. As ARCSA’s Crawford pointed out, private wells for drinking water are supposed to be tested every three months but they’re actually tested only when the house is sold.
While there’s no argument about the efficacy of the technology, there’s still a feeling is that there are things that water reuse systems just can’t handle like viruses, pharmaceuticals or some microbials, said Sara Simmonds from the National Environmental Health Association. There’s a lack of national consistency in the codes and standards, especially for state code officials, continued Simmonds, who is also the supervising sanitarian for the county health department in Grand Rapids, Mich. Some guidance is contradictory and there’s a lack of unified language and definitions. Unmaintained systems can create a public health nuisance, she said, and the question is what do you do with a person who is not maintaining a system.