The Authority Podcast: Plumbing and Mechanical

Episode 01 – Part 02: Mary Ann Dickinson & Janet Stout, PhD

April 20, 2021 IAPMO Season 1 Episode 2
The Authority Podcast: Plumbing and Mechanical
Episode 01 – Part 02: Mary Ann Dickinson & Janet Stout, PhD
Show Notes Transcript

This is part two of a two-part series discussing creative synthesis, sustainability and water safety with Mary Ann Dickinson, past president and CEO of the Alliance for Water Efficiency, and Dr. Janet E. Stout, president of Special Pathogens Laboratory. If you missed part one, we suggest you go back and listen to that episode before continuing here.

Mary Ann Dickinson was the president and CEO of the Alliance for Water Efficiency, a nonprofit organization dedicated to promoting the efficient and sustainable use of water in the United States and Canada, at the time of this recording. She has presented numerous papers on water conservation, internationally and all across the United States and Canada.

Learn more about the Alliance for Water Efficiency at

Janet Stout, PhD, is President of Special Pathogens Laboratory and Research Associate Professor at the University of Pittsburgh, Swanson School of Engineering, in the Department of Civil and Environmental Engineering and Infectious Disease. Dr. Stout is recognized worldwide for seminal discoveries and pioneering research of Legionella.

To learn more about Special Pathogens Laboratory, visit

To learn more about The Authority Podcast, and to subscribe to out show on your podcast app of choice, visit


Christoph Lohr: Welcome to The Authority Podcast: Plumbing & Mechanical. This is part two of our two-part series, discussing creative synthesis, sustainability and water safety with Mary Ann Dickinson, president and CEO of the Alliance for Water Efficiency, and Dr. Janet E. Stout, president of Special Pathogens Laboratory. I’m Christoph Lohr, your host, and I’m looking forward to continuing our conversation.

If you missed part one, I suggest you go back and listen to that episode before continuing here. Now let’s jump right into part two of my conversation with Mary Ann and Dr. Stout. 

In the previous episode, we talked about how we’re getting there, but we're not quite there yet. Well, speaking of getting there, that conversation made me think of the Trump administration seeming to be consumed with increasing flow rates in showers, clothes, washers, dishwashers, toilets, and other plumbing fixtures.

Mary Ann, I guess, what was your sense as far as what was going on there? 

Mary Ann Dickinson: Well, I guess the president was unhappy with low-flow plumbing fixtures. I don't know whether he had issues with some of the fixtures in his properties, but clearly he was on a mission to increase water flow anywhere he could.

And the Energy Policy Act, which was passed in 1992 was pretty precise in how it defined some of those fixtures. And although he complained about flushing his toilet 15 times, there really wasn't anything he could do other than going to Congress to change the toilet standard on a national basis.

But there were other things that could be done. And one of the things that the Department of Energy, under his direction, ended up adopting was a new definition for showerheads that basically said, well, in the past, the Energy Policy Act said you could only have 2 1/2 gallons a minute for your shower; no matter how many showerheads you had the total shower experience can only be 2 1/2 gallons a minute. And that was removed. Now, any showerhead in a multiple showerhead array can flow each one at 2 1/2 a minute, and body sprays, which are the kinds of sprays that are alongside the walls of a shower stall, they’re exempt altogether.

So that created a situation where very high-flow plumbing shower systems could now be legal in the United States. And he also created new product classes for dishwashers and clothes washers that were short-cycle product classes, where there were no long cycles, but only short ones. And by creating a new product class, those new products are now exempt from water and energy efficiency standards because they have to be adopted separately.

And of course the Trump administration didn’t do that. So we have now all of these rules and rulemakings that are in effect. They were approved by the Department of Energy in December of 2020. And so the Alliance for Water Efficiency has gone on a mission to appeal those rulemakings and to see if, with all the legal flaws that they had in the proceedings, if maybe the federal court might roll them back.

So we’ll have to see. I think the new Biden administration is interested in revisiting some of those issues, but whether they would do it quickly enough on their own, we don't know. So we are appealing those in court. And so I think the reason I'm telling this long-winded story is that there seems to be a public perception that the more flow that a fixture has, the better it will work.

And that’s not necessarily true. I mean, I like to remind people that the plunger was invented about 150 years ago when toilets flushed at 15 or more gallons of flush; it relates to how it’s designed and the new WaterSense-labeled fixtures flush very, very well at 1.28 gallons per flush. You don't have to have a 5-gallon-per-flush toilet in order for it to work properly.

And so this is a public perception problem that we have. And one of the concerns I really have in this discussion about public health versus water efficiency is that it shouldn’t be a versus, and that there shouldn’t be the impression that the public gets that in order to protect public health, we’re going to have to jack up all of the flows everywhere beyond what is in the federal law.

Our concerns I think are mostly making sure we hold the line at what the federal government has done both in federal law and with the WaterSense program and not go below what we know is a tested standard that meets all of the public health concerns that we have. 

Lohr: That's a great point, Mary Ann. And I think that would mimic how I see this as well.

You know, we have to find the balance point. I think we’ve talked about balance and creative synthesis, but you know, I sit there and I think about the reduction in flow rates. Right. And I think you bring up a great point. I think here in the U.S. we don't necessarily take a look at all the components as they work in a system; we take a look at them as individual components, and we need to start thinking of sort of shifting our mindset to seeing that connection between everything. 

Dickinson: Yeah, and building performance. How did it perform? And that was one of the points we made to the California Energy Commission. You can’t just look at individual fixtures. You have to look at how it performs as a building. 

Lohr: Definitely. Well, and I think that’s where codes and standards can come into play.

And I think IAPMO, the Water Demand Calculator, that was the first update to the way that building plumbing systems have been sized in 70-plus years. We’ve been basically using this kind of the same criteria for sizing buildings that we did back in 1945 when the Hunter’s Curve was created until today, just some minor modifications.

And you know, when we’ve made some of those reductions in flow rates, perhaps we outpaced that. And that’s where we’re now seeing these water quality issues. We outpaced the size and criteria, but the Water Demand Calculator now for residential has come out. We’re looking at having a summit later this year on updating the Hunter’s curve for hospitals, office buildings, apartment complexes.

We’re hoping to host that here at the beginning of November and getting the industry pulled together to update that for these other building types. And I think these are the steps we need to take. And again, we need to realize that plumbing is a very complex system. I mean, we have microbiologists involved. We have utilities involved. We have engineers involved. We have contractors involved. We have building officials and inspectors, and it’s this host of people that are involved and each brings their needed perspective. And when we develop the codes and standards to address these challenges, we need all of those participants and stakeholders to have equal representation — or I should say equal weighted representation — that their voice has equal weight to make sure we’re really solving this holistic problem because everybody’s perspective on this is needed in order to really make sure that we make the right decision. Otherwise we’re making decisions, I think, in a vacuum and Mary Ann, what you’re talking about, it seems like there’s a lot of that that goes on.

Whether it’s previous administrations just wanting to increase the flow willy nilly or maybe where we've kind of gone too far, we have to kind of find that middle ground as an industry and as a society. 

Janet E. Stout, Ph.D.: And I think Mary Ann made a good point about this idea of assumptions that things are versus each other, that sustainability and safety are opposed.

And I just want to make the point that not every building has a Legionella problem. And in fact, all of these devices are in use. In lots of different buildings, the rule of thumb is about 50% of large buildings with hot water recirculation have Legionella colonized in that system. Only 50% on average.

So that’s a myth that people have that Legionella is in every building. And so obviously these devices, these ways of operating don't always create a safety issue within the building. And I think it’s important for people to realize that.

Lohr: You know, and Janet, I wanted to ask you on that, you know, I think you had mentioned earlier up front that there’s a lot of standards and guidelines that have kind of started touching on this, and you had mentioned, obviously, IAPMO’s Uniform Plumbing Code Appendix N, and I think you talked about the CTI Guideline 159, ASSE standard 12080, ASHRAE.

Have we talked about ASHRAE Standard 188? I mean, do you want to talk about some of the others that are worth referring to?

Janet E. Stout, PhD: Well, ASHRAE Standard 188 came out in 2015. It just seems like so long ago, and what has happened in the interim period is that it is a sort of a high-level structure for addressing the risk of Legionella in building water systems.

You have to mind the gaps that are in Standard 188. It doesn’t tell you exactly what to do to minimize, it sort of tells you kind of the approach to take in developing a water management team and setting limits and making sure that you’re measuring how things are operating. If you are in a health-care facility, certainly you want to consider testing for Legionella as part of that water, safety and management program.

People get into trouble when they develop a plan without outside guidance. And outside guidance can be looking at the CDC toolkit. For example, the Joint Commission in terms of health care is really coming down and strengthening their standard. And in fact, we’re going to have a webinar. If people are interested, we’re having as a guest speaker Diane Collin from the Joint Commission to talk specifically about these new standards from the Joint Commission regarding Legionella management and reducing the risk of building water systems and health care.

So there’s lots of information out there, and sometimes people need help kind of assimilating and synthesizing all of that information. And we’ve seen people get into trouble just because they’re naïve about the complexities of Legionella water management. So people should just keep that in mind.

Lohr: So are you saying it's a do-it-yourself thing?

Stout: People can do it yourself, but this is what I see. Unfortunately, so we get called in when there’s a problem sometimes. And the problem is somebody has gotten Legionnaires' disease and invariably there are deaths associated with that.

And then when the health department says, “Show us your water management plan” and they give them a two-page document. We know that they’re in trouble and I think they were just naïve about what really goes into an effective water management plan. So when you do it yourself, you just be careful.

Lohr: Definitely. And that's my sense too. And kind of along that line of standards and guidelines coming out, there seems to be an emphasis on switching from reacting to Legionnaire’s disease outbreaks to trying to prevent them in the first place. Janet, and then Mary Ann, what do you all think about what the benefits are, and if that approach is maybe the right one?

Stout: Well, I just want to say, Christoph, that that’s music to my ears that you see perceptively the change from a reactive mode to a proactive mode. It’s far better, not only in terms of disease prevention, but also for the reputation of the organization and cost.

When there are cases and investigations, hundreds and hundreds of thousands of dollars are spent very, very quickly in response to public health authorities coming to your facility, whether it’s a cooling tower problem or Legionella in the water distribution system. So the emphasis on being proactive, approaching the problem by having a water management plan and program in place, is wonderful. The thing that people just sometimes get confused about is they will in a certain amount of denial and avoidance. They will say, “I don't want to test the water for Legionella. I just don't want to know.” And unfortunately that's the only way to really assess the risk within your building.

But ASHRAE and CMS, Medicare and Medicaid, their memorandum from 2017 and 2018 leaves it at the discretion of the facility. And sometimes the facility sort of has the ostrich with the head in the sand and doesn’t want to know what the risk is. So I would encourage people to test for Legionella if they’re assessing risk, because that’s really the only way to do it.

And it should be part of a well-managed water, safety and management plan. 

Dickinson: So I would agree with what Janet says, but I think there is still a resistance among some building managers, because they are afraid of what they’re going to find. I have a friend who managed for many years, a skyscraper in downtown San Francisco.

And when I asked him rather casually, “Oh, how often do you test for Legionella?” He said, “I don't.” And I said, “Why not?” He said, “Because I'll find it. And then that will open up a whole regulatory nightmare for me.” And I think this is part of what we have to address in education because his regulatory nightmare will be a whole lot worse if it’s reported as an outbreak and deaths occur than if you proactively managed it in the first place.

And I think this is the task that’s ahead of us is to go, as Janet said, from reactive to proactive, to make sure that we minimize the amount of the disaster situations that could potentially occur. 

Lohr: You know, Mary Ann, that makes me kind of think about this a little bit. Is there a role that water efficiency plays into the prevention via design and installation of plumbing systems of new plumbing systems?

Dickinson: Well, pipe sizing is of course a major issue, and there’s lots of great work that’s going on in pipe sizing for a variety of reasons, not just in saving energy from slow delivery of hot water to fixtures, but, just in general, making sure that the fixture flows are working correctly. And I know we focus a lot on the commercial sector for pathogen growth, but I get very concerned about some residential situations where houses that are vacation homes could potentially be Legionella and pathogen sinks if those plumbing fixtures are not flowing on a regular basis, but only flowing every maybe two months or so when they come into town. So I think we need just good guidance in general, not just for the design of the buildings, but for proper operation of those systems, once they're installed.

Stout: Yes. And, Christoph, the design part, this is where mechanical engineers and design engineers come into play, where we have seen bad design, meaning that where the loop for the hot water goes all the way to the top and comes down, and the water goes round and round and round and it loses temperature. And with most – many at least – supplemental disinfection approaches being applied to hot water to control Legionella, that's a big problem in terms of efficacy of disinfection. So for sure, there’s a design role here to mitigate those risks.

Lohr: Youknow, Janet, that makes me think obviously, design is one part of that entire construction process, but a big part of the construction process is the actual construction and installation.

My sense is that there’s a lot out there, having spent time on the IAPMO/AWWA Manual of Best Practices, where I think actually Special Pathogens Labs, our very own Julianne Baron was part of the discussions. And I remember we had a lot of discussions about how when buildings have been shut down or have become vacant as a result of a pandemic or whatever else that that situation very much mimicked the installation and the construction of a building in the first place, especially with the water systems maybe being charged, having water put into the piping system, but then perhaps not being utilized and the potential concern there.

So yeah, I guess. Yeah. As far as engineers, people that are constructing buildings, policymakers, jurisdictions, what do they need to know about pre-construction planning and planning for construction and trying to maintain safe building systems for the first building occupants? It’s a great question.

Stout: And again, hindsight is 20/20. We’ve seen a number of outbreaks that have occurred after new building construction. And that's because of the reasons that you just said. They have water sitting in there and they might’ve even done a commissioning, charge the system with a high amount of chlorine, but then it sits there for months and then they open it.

And now people are exposed to high levels of Legionella because they didn’t check it again before occupancy. So actually in ASHRAE Standard 188, there is a section, Section 8, that deals with this issue and talks about whether it’s two weeks’ delay in beneficial occupancy or four weeks’ delay in beneficial occupancy, what should be done.

And if it’s four weeks or longer, it should go back to the water safety management team to decide whether another disinfection is necessary. And part of this now, in health care anyway, there’s infection control, risk assessment. That’s part of construction. And what we’ve done is put the w before that, WIC raw water infection control, risk assessments, so that during construction, whether it’s new construction or ongoing construction, the issues of water and its ability to promote Legionella transmission are addressed during the construction phase.

Lohr: Awesome. Well, as we’re wrapping up here, I think we covered a whole host of subjects. I guess if I was going to summarize our conversation here, is that OK? Safety and sustainability, perhaps what many people see as two different camps there? Maybe not really two different camps.

They're all part of that same nexus, to steal your word, Janet, of experts and specialists that are working together to try to fix this problem. Would that be fair to say? Absolutely. So I guess as we wrap up here, we talked a lot about why industries and companies and organizations such as the Special Pathogens Lab and AWE are concerned about bridging that gap between water efficiency and public health. Let me ask this question before we wrap up: What would be your top one or two lessons for our listeners to take away from our conversation here today?

Dickinson: Well, I'll jump in first. First of all, water efficiency should never compromise public health. There’s no reason for that to happen there. They should be mutually achievable goals. And to achieve that, I think water utilities need to spend a fair amount of time also working with their commercial customers and their building owners and their service areas to make sure that these best practices are being implemented. And it’s going to require a partnership among all of these valuable stakeholders to make sure this happens. 

Stout: And for me, I think, Christoph, and sort of circling back to a comment I made at the beginning of the podcast, is that we need to break down the silos across the disciplines and make sure that we have increased awareness, shared language.

And one of the things we talked about is that, IAPMO-ASSE training. The next one's April 5 through 7. Lots of resources on, and there's COVID resources for reopening as well as access to registration. And then on the education side, we have this, you'll probably laugh at this.

We have a website called and on that website, there's a book that. tells you everything you need to know about Legionella and water management. So we’re trying very hard to make sure that those silos are broken down. And I’m really excited to have been part of this podcast, because I think this podcast and your work in the field goes a long way to doing that.

Dickinson: Amen. 

Lohr: Awesome. Well, before we sign off, I was going to ask you guys, how can people get in touch with you, whether it's by Twitter, LinkedIn, or email, or your organizations?

Dickinson: So the Alliance for Water Efficiency has a pretty extensive website. You just type in www.allianceforwaterefficiency — all one word — .org.

And a lot of our information is there, including how you get in touch with us at the staff level; we’re headquartered in Chicago. Of course, a number of us are working remotely with the pandemic, but you can still contact us by emailing And we’d be happy to answer any questions that you have.

Stout: And if you want to talk to a Legionellologist, all you have to do is email

Lohr: Awesome. Well, and if our listeners want to get in touch with me, Christoph Lohr, the host, you can find me on Twitter @LohrThoughts, all one word, or on LinkedIn. You can look for me, Christoph Lohr.

Also you can go on the IAPMO website, On behalf of The Authority Podcast: Plumbing & Mechanical, I just want to say thank-you again, Mary Ann and Janet, for joining me here today. This was a fantastic conversation. I know I always come away with something when I talk with both of you over the last couple of weeks.

So just again, thank you so much for joining us. It was a pleasure.

Stout: Yes. Thanks, Chris, the staff is wonderful. And thank you, Mary Ann. 

Dickinson: Thank you too. 

Lohr: Thanks for joining us on this week’s episode of The Authority Podcast: Plumbing & Mechanical. “Love” this episode of the podcast Head over to iTunes to subscribe, rate and leave a review.

Please follow us on Twitter @AuthorityPM, on Instagram @theauthoritypodcast, or email us at Join us next time for another episode of The Authority Podcast: Plumbing & Mechanical. In the meantime, let’s work together to make our buildings more resilient and shape us, for the better.