Our Hero: Kristine Uhlman of the University of Arizona

photo from Kristine Uhlman

Kristine Uhlman is a nationally recognized hydrogeologist specializing in aquifer characterization, environmental site remediation, water resource management and protection, compliance and groundwater modeling. Kristine also does water outreach and education. We met at a lecture she gave about the use of groundwater age dating with tritium as a tool for managing water resources. Once upon a time, she wanted to be a Lutheran pastor until a geology course changed her life -- and her life story.

What is the state of groundwater in the state of Arizona and how is groundwater age dating changing that picture?

All of the rural areas in Arizona rely on groundwater. The only location within the state where they have some surface water supplies is in the Phoenix area, where they have canals that connect to surface water reservoirs and, of course, the aqueduct that comes from the Colorado River. So groundwater is very important in the state.

We've been doing age dating on some of the groundwater in Arizona because the issue of how rapidly groundwater recharges always come up, especially when there’s new development. The rule in Arizona about new development is that they must assure that there is a water supply for 100 years when they put in new water supply wells to support development.

What happens if there’s not enough water?

The rule is if they find that there’s not water for 100 years, they just have to inform the first buyer that there’s not enough water. The second buyer may not have any idea. There are a number of housing developments where there’s no water. So people have to get tanker trucks and tank water in from other sources to provide their own personal water supply.

There’s an area (just west of Casa Grande) where I did a lecture on groundwater age dating and there’s a housing development out there with no water. Every weekend people take their little trailer that’s attached to back of their car and they fill up a tank and then they bring the water back to their household.

How many people do that in the state?

I don’t know how many I just know that right around July and August I start getting calls from people because they can’t get any water.

It’s amazing. Never in my life did I think that talking about isotopes would be of interest to people, but after finding out about it people take ownership and feel responsible for their water. They realize that when they're drinking their water and it’s really, really old, conservation and preservation of that limited savings account of water is important.

The rules in Arizona are just…very complicated. It’s based on where you're located in the state but what’s generally true is that wherever we have looked at it, water is quite old. And that means that, for example, in the Tucson area or the Benson area, when we took groundwater age dates, the water was over 10,000 years old.

However, when we went to Arivaca we found that the groundwater had fallen as rainfall as recently as the 1950s. Here’s one little groundwater basin that hasn’t been overdeveloped and they're still working with a renewable resource because the rate of recharge is keeping balance with the amount of water that they're taking out.

Now before I can commit to that statement I want to wait about six years - which is the half-half-life of tritium - and see if the concentration is going up or down. Then I'll be more comfortable with assessing whether that’s renewable.

But everywhere else we look at groundwater in the state, the amount of people taking water out exceeds the recharge rate and the water that’s coming out of the ground these days is around 10,000 years old.

Is this how most of the water in the state is - not being recharged and a finite source?

If you were to look at it like a savings account or a checking account, then it’s a savings account. When I open up my statement for my savings account I do get some interest – like twenty-five cents – so there is recharge going in but it’s insufficient in light of the fact that the average age is 10,000 years.

We have looked at the major groundwater basins. In Phoenix, for example, we got an average age that was nearly 13,000 years; Tucson – 8,000 to 10,000 years; in San Pedro we got one sample that was 11,600 years old, but along that basin it’s up to 12,000 years old. What this means is that the rate of recharge is not much. The majority of our aquifers were filled up during the Pleistocene as all of the glaciers melted and the freshwater went into these beautiful basins.

Water tables are dropping, except in Arivaca, where they might be in a perfectly balanced situation and where they have a renewable resource.

So that’s the place to retire?

NO! Don’t go there! That’s what everybody says when I tell them about it, “Oh I'll move there.”

How did you start the outreach program and how did you hit on the idea of doing age dating?

I was working with Cooperative Extension and in 2003 the United States Geological Survey (USGS) asked me to present data from 12,000 year-old groundwater to a community. I was apprehensive about how I would be received going into a rural area and bringing up the term “isotope.” So I did a basic presentation on isotopes and people loved it; it was bizarre. All these people started asking for the talk. I was like, “You want to hear about isotopes???”

Realizing there was momentum, plus everyone wanting me to do age dating of their water I applied for a tiny, little grant to date water in Show Low and Pinetop, up on the Colorado Plateau. Samples there were 6,000 years old. When I got to Arivaca and gave my presentation, they wanted me to test their wells too but there was no more money. So the community collected money and paid us, essentially in dollar bills, to take one sample from their community center well. We fully expected it to be consistent with other samples across the state. When it wasn’t we wrote up a grant and got funding to do additional work.

It’s amazing. Never in my life did I think that talking about isotopes would be of interest to people, but after finding out about it people take ownership and feel responsible for their water. They realize that when they're drinking their water and it’s really, really old, conservation and preservation of that limited savings account of water is important. The people of Arivaca realized how special their water is and how they're living off of a checking account and so they're inspired to try and manage their water appropriately.

It’s interesting how you put a cultural value on it and people sit up and take notice.

And I don’t know how that happened, but now people all across the state want their water tested.

We really don’t have a lot of information about groundwater withdrawals, do we?

Each state takes a different approach but it’s relatively consistent across the United States that domestic wells are exempt from any regulation and monitoring. So people can be drinking water of very poor quality and nobody would know unless they themselves take personal responsibility and expense to get it tested.

Do you extend the conversation to anthropogenic climate change and the potential impacts on water resources? If so, how do you frame it?

Oh definitely. On the last slide on many of my presentations I have a Woolly Mammoth and I talk about how we're now drinking water that was recharged when Woolly Mammoths were roaming across Arizona. What I've found is that I don’t bring up the word “climate” until the very end, because the work that we've done has shown that past climate has been very important for current water resources. I try to equate aquifer vulnerability with climate variability. You can see from the past what has been important so just think about the future. I don’t get into the politics of climate change.

How did you come to, first hydrology, and then engineering?

In the beginning of time, I wanted to be a Lutheran pastor. Then I took a geology class and it changed the direction of my life. I came to the University of Arizona through a scholarship program called “The Western Interstate Commission for Higher Education.” This was in 1972 and they were funding the education of hydrologists to address water supply in the west. The University of Arizona was the first program in the United States that focused on groundwater and hydrology and I still think it’s number one. I was the first woman to graduate from the program.

On the advice of my undergraduate advisor I got an engineering degree because he said, “You'll look flexible.” I went to Ohio State and got a master’s in engineering. Then I started working with the USGS, where they trained me to do groundwater modeling.

I started working with consulting firms when the Superfund projects were going hot and heavy. It was an amazing ride. There was a lot of money; there was a lot of opportunity; I worked all over the world; had great fun. Right around the early 90s all of the consulting companies were downsizing, consolidating and going bankrupt. I was at the highest point in my career, just under a Vice President level – corporate director for Kaiser Engineers. When Kaiser went under I saw an opportunity to work for the university and I took the vow of poverty and made the leap.

Where did you grow up?

I grew up in California, where I competed against Steve Wozniak (inventor of the Apple Computer) in the 6th grade science fair. He won and I'm still mad because I came in 2nd. I built a diffraction scope where I could measure the elemental constituents in material by burning it and looking at the lines on the diffraction screen. You know, it was optical science plus physics put together. Whereas he did (and I still remember the title of his entry) “An Inexpensive Computing Machine.” It was the first Apple! I complained, “But look at his display, it’s so sloppy and mine’s so neat.”

What was your family like?

My dad was an engineer. He worked for Lockheed and we lived in suburbia, in what became Silicon Valley. My mom was one of those stay-at-home moms who volunteered a lot for the church (we were Lutheran). My father was very conservative; did not believe women should be educated because they would then form opinions and not be good wives.

The only way I could get myself out of there was to go to a church school - Pacific Lutheran University in Tacoma, WA. That’s where I took my first geology class. Then I applied at the University of Arizona and because they gave me a full scholarship I was able to continue my education. Then based on my grades I received a full scholarship to Ohio State. I looked for scholarships because my parents would not pay for me to get a degree in hydrology.

It was right on the edge of when women were starting to go into math and sciences. If I had not gotten the scholarships I would not have gotten educated and I would have to have been, “a good wife,” which I am not.

Did you really want to be a Lutheran pastor or did you want the education as a way to move away from your family?

Well, it was probably that plus when I went to the Lutheran school and I sat down with the advisor (this was in 1970 ) she said, “Girls don’t do that [become pastors]. Why don’t you be a nurse?” I was very discouraged about that. There was even a moment where I thought, “Well maybe I could marry a pastor.” I was saved by geology.

That’s men’s work!

Oh boy. My father…I remember coming back for a family gathering when I was about to finish my master’s and he was so upset about me getting an engineering degree. He had one of his friends come to dinner and they sat there talking about how all these women getting [engineering] degrees in a man’s world were taking jobs away from family men. It was very much a threat to my father’s generation.

This was a low point in my life. They were trying to open my eyes to the fact that what I wanted to do with my life would threaten the family structure. They said, “You're taking a job away from a family man!” My response was, “But I'm good at it!”

When I first worked for Kaiser, I first sat down with the Vice President and the first thing he said to me was, “Even before we got married my wife and I decided she would be a stay-at-home mom.” And I kept thinking, “Why would he tell me that?”

He was putting you in your place. So he thought.

Yeah. Almost everywhere I've worked I've gotten that talk. It’s comical.

I remember when I took my Engineer-in-Training Exam and I received my certificate, it was was addressed to Mr. Kristine Uhlman because they didn’t have another option on the form.

Wow. I received my engineering degrees a decade or more after you and I really didn’t have any experiences like that. Thank you for breaking that ground for those of us who came after you.

I have one more question. Do your friends and family listen when you start talking about water conservation and the environment?

They're tired of hearing it.

I tried to raise my son to go into the sciences or engineering. He’s now a lawyer. All those times pulling off on the road and saying, “Look at this road cut. See here where the color changes?” He'd say, “Yes I know, Mom - oxidation and reduction.”

Sometimes I bring my 84 yr-old-neighbor with me to the presentations. I asked her once how I could improve on the presentations. She said, “You could iron your shirt.”

Whatever. My audience is the people who live on the land; the people who need and want the information.

Responses to "Our Hero: Kristine Uhlman of the University of Arizona"

  1. Robin Madel

    Older water isn’t necessarily cleaner water. An older water source may not get replenished as quickly as a younger water source might. Municipalities and communities need to take this into account when they plan out their water management strategies. If an aquifer is not being recharged at the same rate it is being used or not being recharged at all then communities run the risk of running out of that source of water, as is the case in many places in Arizona. This could create a real burden, both logistically and financially, on residents to have to search for their own sources of water.

  2. victor hernandez

    hydrogeology: does this mean that the older the water the better or purer or cleaner it is? Are this trapped water, which have been in a certain place for a very long time? Should a cioty or municipality regulate the use of old water.

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