Research profile: Dr. Craig Just

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Dr. Craig Just (right) stands with Senator Senator Bob Dvorsky (left) at this year’s Iowa legislative breakfast, where many researchers from the University of Iowa came to share their work with legislators. (Iowa Senate)

Dr. Craig Just is an assistant professor of Civil and Environmental Engineering at the University of Iowa. Up for tenure this summer, Dr. Just teaches graduate level courses along with an undergraduate principles of environmental engineering course. His research interests range from freshwater mussels’ impacts on the nitrogen cycles in rivers and streams to the fate of explosive chemicals once they are released into the natural environment. Iowa Environmental Focus caught up with Dr. Just to discuss his research on wastewater treatment in smaller communities.

Jenna Ladd: I wanted to focus on your wastewater treatment research in smaller communities. So, why can’t people in smaller communities flush their toilets affordably?

Dr. Craig Just: So, in a town like Iowa City, we just had an over $15 million expansion to our wastewater treatment plant but that cost was spread, you know, among a population base of 75,000 or 80,000 people so the per person cost for such an advance treatment system is under probably a thousand bucks each, give or take, prorate over a certain amount of time. But for smaller towns, who have increasingly rigorous environmental regulations they have to meet, particularly with respect to the discharge of ammonia and bacteria, they’re small so when you have to do a technology upgrade, it’s more expensive per resident and that’s one of the main issues. The other issue is that it also becomes more expensive then to pay an operator for the plant, someone that has the expertise needed to operate an increasingly more sophisticated treatment system. So, then you have to spread that cost amongst a small population base as well and so both of those factors are really scaling issues that, really, small towns have a problem dealing with compared to some other places. Those are some of the main issues going on there.

Jenna Ladd: How were those issues brought to your attention?

Dr. Craig Just: Sometimes it’s with screaming mayors at small town hall meetings. I’ve been going to Des Moines to talk about this issue since at least 2005. Legislators know it’s a problem, their constitutes tell them it’s a problem. In 2010, I was one of the co-leaders of what’s known as the faculty engagement tour. We get faculty who are typically stuffed in their offices and labs and we stuff them in a bus and took them all around Iowa to say, “You know, here are the people that pay your salaries, really, in a way, and let’s be aware.” So, we had a town hall meeting in Goodell, Iowa, town of about 225 people facing a $2.2 million waste water treatment plant upgrade bill and the mayor of that town and the mayor of three or four other towns came to this meeting. Over 100 people showed up to this meeting in all that was left of the school, the old gymnasium. The school’s gone….Everybody came out, it was such a big deal. People were mad, they were shouting. They viewed me as part of the cultural elite who wasn’t doing enough for them in rural Iowa, and that we were putting unrealistic environmental constraints on them that led them to essentially go bankrupt as a town. So I’ve heard it in casual conversation, I’ve heard legislators talk about it, I’ve heard it in town hall meetings. Candidly, at this point it’s hard for me to get away from. I’m from rural Iowa, you know, that’s where I’m from. So I’ve seen it first hand, it’s not hard to see.

JL: Are these newer wastewater treatment regulations or are communities just kind of playing catch up to those regulations that were already in place?

CJ: They’re new, and I would say that they’re based at the federal level. I would say one of the things that’s happening, and it’s a challenge for Iowa in particular, so the population in the U.S. has gone up. I think in just the U.S. alone, we’re up to like 330 million people now, whatever, 50 years ago, I think it was like 200 million or something. I don’t know those numbers, but the point is the overall population density has been going up. Most towns in these watersheds that have a discharge into a stream, most of them have gotten more dense so then you have to have more stringent regulations to not kill the stream. But when you apply those things at the federal level for the National Pollution Discharge Elimination System, it kind of puts a disproportionate burden on the places that haven’t grown. In fact, in rural Iowa, it’s less dense but then you still have to meet these federal standards which are somewhat one-size-fits all and so, I don’t disagree with the fact that the federal standards have become more strict but it’s difficult to apply it in a place that’s population and tax base isn’t growing. It puts rural Iowa at a very special pinch point where those two things converge.

JL: Are there any solutions you’ve come up with for this problem?

CJ: Well, first of all, there are already some alternative technologies, they’re called, that are approved in Iowa that are robust and more affordable, not as affordable as you might like but still more affordable. So, one of the things that we’re doing in partnership with H.R. Green Consulting Engineers, one of our alums there Matt Wildman has really kind of led the use of this technology in Iowa. We’ve partnered with them and the community of Walker, Iowa to extensively test one of these alternative technologies called—it’s a lagoon modification—a submerged attached growth reactor, essentially rocks in a box. A couple lagoons. The lagoons are aerated, they take care of some of the wastewater issues and then it goes to these rocks in a box where the bacteria then are attached to the rocks, they further covert the ammonia with aeration to nitrate, which you can still legally discharge in Iowa—it’s a fertilizer though. It doesn’t solve all of our problems if you look at the broader watershed problems with respect to nutrient discharges, but yet it removes the acute toxicity associated with ammonia discharges. So, that works out well in many regards. It still doesn’t solve all the problems because at least, approximately half the cost of the system is just the pipes that collect the waste from each house and those systems are deteriorating in these towns as well. So, even if we’re improving the system at the end of all those pipes it still kind of tricky to deal with that.

I’m even thinking of almost having your toilet be more like an appliance where you don’t have to convey your waste someplace else. If we could find a way to do that, almost like a compost toilet would work, the composting waste you’d have to collect. The nice thing about that sort of a mentality is you could then use that waste as a resource because there are nutrients in there, there is energy value in that waste. Right now we send it to a lagoon and then one of these box of rocks with bacteria, we treat it but we don’t harvest any of the energy…in fact, we have to put energy in. I think if we could find ways to do that, even in these small towns, then it would make them more sustainable. It would give them extra resources that I think would be valuable. So in the future, I think it would be valuable to maybe not have these lagoons at all. Especially for these towns that are increasingly small, you know, like 600 people or less.

But anyway, so I’m thinking even longer term, but in the short-term, these alternative technologies are better. One of the things that we’ve been able to do then, with all this data collection that’s been going on in Walker since 2013 is now, we can more appropriately size the technology. Since we didn’t have very much data before, we kind of over-sized it in the name of kind of a safety factor. Now with data, we can shrink the size which then makes it cheaper. So that’s where the researcher comes in. As a researcher, I can come in, get this data, say “No, it doesn’t need to be this big” and then work with Iowa Department of Natural Resources to get that approved. That just recently happened. So, now going forward this particular technology can now be about a third smaller, which would have saved Walker, Iowa about $150,000 on a 2.5 million project. That’s real money. 750 people and $150,000 saved, that would be a lot. You multiple that across the nearly 800 or 900 communities these technologies are targeting so that’s a lot of money that Iowans can save. That’s kind of where research and the practical nature of trying to make things affordable come together. Sizing things appropriately so they still work and then making sure the operators still know how to handle any disruptions and understand why things do get disrupted from time to time.

JL: Are you communicating with people working to solve these problems in rural communities in other states?

CJ: In general, Iowa is a little bit behind. Even our peers on our borders: Minnesota would be ahead of us in many regards, some other places too. A lot of these alternative technologies have been utilized in warmer climates. Since they’re biological processes, the bacteria work better when they’re warm, just like you or I do. I don’t move so fast when I’m cold and neither do bacteria. So the challenge for Iowa has been even though some other states have been embracing these alternative technologies more readily, they are easier case studies too. So really, for Iowa, it’s been “How do we manage the cold weather?” that we have and “Will these systems still work when it’s cold?” So, we’ve applied what we can from other states in trying to catch up and now we have to deal with that in our own Iowa circumstance going forward. So yeah, we’ve learned from other places, but we still have to make sure we deal with, you know, Iowa’s situation.

JL: In what ways does this research relate to your teaching?

CJ: Increasingly, developing countries, where again you lack a population base and kind of a resource base and a tax base, some of the challenges are like rural areas in the United States. They’re kind of falling into some of those same categories sometimes so I want our engineers that graduate from our program to understand the rural dilemma. It’s relatively easy to be an engineer when you have all the resources you need, you got money. Yeah, shoot, design away, and it’s fun to kind of do it like that, but when you have to apply your engineering skills and really your community engagement skills at the same time to try to make a difference in a community that’s struggling just to keep their doors open, that’s a cool place. That’s very satisfying and rewarding for an engineer to be operating there. So I’m encouraging our students to do that in some way or another so when they go out into engineering and consulting, they’ll be aware of the issues that small rural communities face in contrast to what growing, urban areas face: fundamentally different engineering problems.

Urban heat islands compound economic impact of climate change

A 2011 heatwave in New York City produces an orange sunset. (Chris Goldberg/flickr)
Jenna Ladd | May 30, 2017

A recent study published in Nature Climate Change revealed that the climate change is likely to be twice as costly in cities than in rural areas.

An international group of economists found that the world’s largest cities could see temperature spikes of 46 degrees Fahrenheit by 2100 if greenhouse gases continue to rise at the current rate. The top 25% largest cities could are likely to see temperatures rise by about 45 degrees Fahrenheit in the same period of time.

The report explains that about 41 degrees Fahrenheit of warming can be explained by global climate change, but the additional four to five degrees of warming will be the result of the urban heat island effect. Urban heat islands are formed when naturally cooling surfaces like vegetation and bodies of water are replaced by surfaces that trap heat like concrete and asphalt.

Based on their analysis of 1,692 cities, the economists expect the combined heating affect to have negative economic consequences for urban areas. Higher temperatures cause workers to be less productive, raise cooling costs for buildings, and deteriorate water and air quality.

On average, the global gross domestic product (GDP) is expected to drop by 5.6 percent by 2100 due to climate change. In contrast, the most-impacted cities are expected to lose 10.9 percent of their GDP. The researchers provided cost-benefit analyses of several cooling measures in the report, including cooling pavements, green roofs and the reintroduction of vegetation in urban areas. For example, transforming 20 percent of a city’s pavement and rooftops to cooling surfaces could save a city up to 12 times what the structures cost to maintain and install, providing a bump to the local GDP.

The researchers conclude that local efforts to mitigate the effects of climate change can play an important role in global efforts. One of the study’s authors, Professor Richard S.J. Tol, Professor of Economics at the University of Sussex, said, “Any hard-won victories over climate change on a global scale could be wiped out by the effects of uncontrolled urban heat islands.” Tol added, “It is clear that we have until now underestimated the dramatic impact that local policies could make in reducing urban warming.”

Fighting climate change could benefit the economy

The closing ceremony of COP21 in Paris featuring Secretary-General Ban Ki-moon (second left); Christiana Figueres (left), Executive Secretary of the UN Framework Convention on Climate Change (UNFCCC); Laurent Fabius (second right), Minister for Foreign Affairs of France and President of the UN Climate Change Conference in Paris (COP21) and François Hollande (right), President of France. (United Nations/flickr)
Jenna Ladd | January 13, 2017

A statement from the White House on Thursday outlined the relationship between climate change policy and economics.

The authors of the report, Senior Advisor Brian Deese and Chairman of the Council of Economic Advisers, Jason Furman, point out that carbon pollution steadily decreased while the U.S. economy continued to improve from 2008-2015. During those years, carbon dioxide emissions in the U.S. dropped by 9.5 percent while the economy grew by 10 percent.

These trends defy an old reality: increased carbon emissions means increased economic output.

Research from the International Energy Agency demonstrate that the same is true on an international scale. For example, although carbon dioxide emissions stayed the same in 2014 and 2015, the global economy grew.

The statement said that the international community took an important step in combating climate change when the Paris Agreement took effect in 2015. However, the report notes, “But Paris alone is not enough to avoid average global surface temperature increases that climate scientists say are very risky — additional policies that reduce CO2 emissions are needed, in the United States and elsewhere, to ensure that these damages are avoided.”

Failure to address climate change with meaningful policy is costly over time. The report expresses the estimated annual economic damages due to climate change as a fraction of the global gross domestic product from 2050 through 2100. “Climate damage cost” can be thought of as what all nations can expect to pay per year in terms of economic output due of the changing climate. These costs include sea level rise, illness and death related to heat, pollution, tropical diseases, and the effects of rising temperatures on agricultural productivity.

Climate Change Damage Estimates.png
Figure 1. Climate Change is Costly; Serious Climate Policy is a Bargain, The White House

Figure 1 does not include those effects of climate change that are difficult to quantify, such as the increasing  frequency and intensity of extreme weather. The statement said, “Failing to make investments in climate change mitigation could leave the global economy, and the U.S. economy, worse off in the future.”

The report ended with a warning:

“In deciding how much to reduce carbon pollution, and how quickly to act, countries must weigh the costs of policy action against estimates of avoided climate damages. But we should be clear-eyed about the fact that effective action is possible, and that the economic and fiscal costs of inaction are steep.”

On The Radio – Flood patterns changing across the U.S.

The threat of moderate flooding is generally increasing in the northern U.S. and decreasing in the southern U.S., while some regions remain mostly unchanged. (American Geophysical Union)
Jake Slobe | January 2, 2016

This week’s On The Radio segment discusses changing flood patterns found by University of Iowa researchers.

Transcript: The risk of flooding is changing regionally across the United States and the reasons could be shifting rainfall patterns and changes in groundwater.

This is the Iowa Environmental Focus.

University of Iowa engineers, in a new study, have determined that the threat of flooding is growing in the northern half of the U.S. while declining in the southern half. The American Southwest and West, meanwhile, are experiencing decreasing flood risk.

UI engineers Gabriele Villarini and Louise Slater compiled water-height information from 2,042 stream gauges operated by the U.S. Geological Survey. They then compared the data to satellite information gathered over more than a dozen years by NASA’s Gravity Recovery and Climate Experiment mission showing the amount of water stored in the ground.

The study found that northern sections of the country have an increased amount of water stored in the ground and are at increased risk for minor and moderate flooding. Meanwhile, flood risk is decreasing in the southern portions of the U.S., where stored water has declined.

The researchers hope their findings can change how flood patterns are discussed. In the past, flood risk trends have typically been discussed using stream flow, or the amount of water flowing per unit time. The UI study views flood risk through the lens of how it may affect people and property and aligns the results with National Weather Service terminology understood by the general public.

For more information about the flood research, visit

From the UI Center for Global and Regional Environmental Research, I’m Jerry Schnoor.

Iowa professor selected to serve on U.S. House Committee on Energy and Commerce

University of Iowa associate professor of civil and environmental engineering, associate faculty research engineer at IIHR, and Director of the Environmental Policy Research Program, David Cwiertny. (Anne Easker, IIHR)
Jenna Ladd | October 6, 2016

Center for Global and Regional Environmental Research (CGRER) member David Cwiertny has been selected to serve on the U.S. House Committee on Energy and Commerce as minority staff. Cwiertny, who is also the Director of the Public Policy Center’s Environmental Policy Research Program, received the appointment through the American Association for the Advancement of Science (AAAS). AAAS creates opportunities for scientists to offer their expertise and analytical skills to legislators while also learning more about the policy making process firsthand. Cwiertny said,

“Evidence, rooted in sound science, should whenever possible be used to inform and improve decision making and new policy.  And science has never been more important for informing policy, particularly as society begins to address how best to manage and adapt to a changing climate. So in my discipline of environmental engineering and environmental science, I think there is a real opportunity for scientists and engineers to help advance policy that better enables sustainable development both in the US and around the globe.”   

As an AAAS 2016-2017 Congressional Fellow, he will serve on both the energy and power and environment and economy subcommittees. Cwiertney, who is also an associate professor of civil and environmental engineering and associate faculty research engineer at IIHR—Hydroscience and Engineering, will function as a technical expert within the two subcommittees, which are responsible for all legislation and regulation related to water, air, and soil quality and energy. He added, “I’m eager to see, first hand, what the major hurdles are to translating scientific discovery into evidence-based decision making, and how we can improve and evolve our craft as researchers to better help policy makers.”

Cwiertny is one of two fellows that were selected from a pool of over 100 applicants.

Iowa Environmental Council 2016 Annual Conference

Jenna Ladd | September 15, 2016

The Iowa Environmental Council will host its 2016 Annual Conference titled ECOnomics: Dollars, Sense & Sustainability next month in Ankeny. This year’s conference will focus on policies, programs, and practices that benefit the economy, communities and the environment.

Keynote Speaker Jon D. Erikson

The keynote address, “We the Planet: Building an Ecological Economy in the Age of Humans,” will be given by Jon D. Erikson. Erikson is a Fellow of the Gund Institute for Ecological Economics and a Professor at the Rubenstein School of Environmental and Natural Resources at the University of Vermont. The daylong event will also feature Speaker of Honor Rob Bilott. Bilott will discuss the regulatory, legal and scientific challenges of ‘unregulated’ drinking water contaminants during his address. The conference also features a panel of business owners that practice environmental stewardship.

ECOnomics: Dollars, Sense & Sustainability will take place at the DMACC Ankeny Campus on October 6th, 2016. The event has been approved for 3.25 hours of Continuing Legal Education (CLE) credit, and discounted rates are available for students. For more details or to register, visit the event website.

Keynote speaker Jon D. Erikson offers a crash course in ecological economics during his work with the Gund Institute for Ecological Economics in 2011.