A two-time recipient of the Association of American Geographers’ G.K. Gilbert award for excellence in geomorphic research, Dr. Ellen Wohl has closely examined hydraulics, sediment transport, controls on channel morphology and human impacts on bedrock and mountain channels. Dr. Wohl is the author of Disconnected Rivers (Yale University Press, 2004), Virtual Rivers (Yale University Press, 2001), Rain Forest into Desert (University Press of Colorado, 1994), and her most recent book Of Rocks and Rivers: Seeking a Sense of Place in the American West (University of California Press, 2009). In her new book, Dr. Wohl traces her twenty years of living and conducting research in the natural landscapes of the West. Through this collection of personal essays, she chronicles not only the changing landscape of the West, but also her own evolving perception of what she initially believed to be a region unmodified by humans.
I read that you grew up in Ohio and your father, a biology and chemistry teacher and naturalist, with an interest in the natural world was a great influence on you. A) How did this childhood interest lead you to a career in geology? B) Based on what you see as a geology professor at Colorado State University, do you think today’s college and graduate students have had these kinds of influences growing up?
I always knew I wanted to go into science. In retrospect, I realize I was unusually lucky in that I had a geology course in high school. When I started college, I actually started in biology, but switched to geology after the first semester. Being exposed to sciences early – both through my dad and through a really good school system – was critical.
I have been teaching here since 1989. I don’t teach the undergraduate non-majors, so I already have a big filter. I’m getting the geology and watershed science majors their senior year. Geology and watershed science are not very high profile sciences compared to biology, for example. Most kids don’t have those in high school. So there’s already a big selection process. I should also say that a lot of our undergrads come from Colorado, so they’re more likely to have that connection to the outdoors. They aren’t as likely to have grown up in a strictly urban environment with no exposure to the outdoors. I don’t think you need to have a scientist as a parent to get into science, but if you’re going to be a field scientist, you need some connection with the outdoors. Your parent can be in any line of work as long as they share and encourage that interest and give you the opportunity to be exposed to the outdoors.
Your collection of essays, Of Rocks and Rivers, which covers more than 20 years of your experience living and working in the West, is a well-paced, progressive debunking of the myth of the West as pristine wilderness. What kind of response have you received from those who were still clinging to that myth? Were they particularly surprised by any of the insights provided in your essays?
At this point, not many reviews have come out, so most of the feedback I have received has been from colleagues and friends, many of whom are geomorphologists. Everybody is a little surprised about how much alteration there has been [to the landscape].
I received a similar response to my book Virtual Rivers, which is a history of the alterations in rivers in the Colorado Rocky Mountains. I wrote it because I was shocked when I got here and realized how long the history of alteration had been. Most people are still surprised by that. Even scientists, who are supposed to know that professionally. It’s hard to remember how history has changed things. Someone has referred to how our baseline of perception changes through time. If we’ve never seen a river with lots of wood in it, then we don’t expect it or think that it might have been that way once. That’s true for scientists as well as other people.
I guess the surprise I’ve gotten is that people say, “Wow. There has been a long history of change, even in the so-called Wild West.” It is hard to keep that in mind. I have trouble with it, too.
Was there a specific audience you had in mind when you assembled this collection?
Yes. People who are interested in natural history, but also anybody who cares about the outdoors – anybody who likes to backpack, fish, ski, paddle, or just spend time outdoors and think about what they see.
One review I read of your new book said that books like it, which have a personal tone and perspective “are often the only channel through which scientists can make their work accessible to wider audiences.” Do you think this is true in your case?
Absolutely. It’s interesting. If you go back and read some of the classic papers in my discipline, which were written in the late 1800s, they are much more conversational and relaxed in terms of word length. They are really fun to read. There is a much different standard of writing today. Unless you have training in a particular discipline and you are familiar with the concepts and the very specialized vocabulary of that discipline, the literature in technical journals is fairly inaccessible.
I once had a conversation with my uncle, a carpenter, who was teasing me about scientific jargon. I said, “It’s not that we’re trying to keep information from people. It’s just a more concise way of communicating. As a carpenter, you wouldn’t say, ‘Please pass me that screwdriver…the one with the long handle and the narrow, flat head.’ You’d just call it what it is. It’s just a concise way of communicating with people.” But…they have to share that common vocabulary. So yes, [writing in a personal style] is definitely one channel that enables scientists to reach a wider audience.
One of the most powerful essays in your new book is entitled “Poisoning the Well” – the wellbeing of the Rocky Mountains, which you refer to as “an enormous water tank.” In this essay, you follow the plight of a snowflake from its descent onto a hill slope in the Rocky Mountains to its journey downstream to the eastern plains. In that essay, you have some constructive criticism to offer practitioners of stream restoration. You emphasize the importance of creating sustainable pools when restoring rivers and streams. Many of our readers are involved in stream restoration design. For their benefit, can you elaborate on this?
A lot of times, we focus on very short-term solutions in which we’re imposing an engineering design on the river without considering whether that design can be sustained. For example, say there’s a channel that used to be meandering with a pool-riffle sequence and now it has become braided and you want to restore it to a meandering condition. That’s not going to be self-sustaining if the conditions that promoted braiding are still present. So, for example, if you have a lot of sediment coming into the channel for some reason, the pools are going to fill, the whole channel is probably going to become slightly filled, and you’re going to go back to a braided condition.
So one thing is looking at the context and thinking about whether it’s even feasible to restore to some idealized or historic condition. Second, even if it was a meandering river, and could be a meandering river again, to me the greatest irony of stream restoration is when people create this sinuous, meandering river and then they rip-rap the banks. One of the key components of meandering is that the channel moves back and forth laterally through time.
The biggest problem I see in stream restoration today is imposing a form on the river, rather than trying to restore process. Restoring process is harder and usually has a larger context. You have to think about things like the whole riparian zone, the water supply, the sediment supply, and not just a short segment of channel. If it’s a municipality, for example, trying to create a little trout stream, their focus is often on a very small spatial scale and short time scale. The way our political and financial systems are set up, it’s harder to undertake longer-term actions that will have a long delay before you see any response. The most important thing I can say for stream restoration is to think about restoring process and context rather than just imposing a form.
Is it true that while it is illegal to divert water in national parks, there is no legislation that prevents people from diverting water from national forest lands?
On national parks, it depends on what situation occurred when the park was established. As an example, when Rocky Mountain National Park was established, which was fairly late, there were pre-existing water rights grandfathered in. The Park gradually acquired those and removed them. I’ve been involved with Black Canyon of the Gunnison National Park and they just recently settled out of court, reaching a compromise on water issues. As with many other parks, the case there was that water flows into the park from somewhere else. They don’t have the headwaters. They were trying to work out a flow regime that would restore some of the processes in the Canyon with water users and the Bureau of Reclamation who held water rights upstream. It’s too simple to say that it’s illegal to divert water on national parks. It depends on where the water originates and what the water use was at the time the park was established. What I can say is that the parks in general have a stronger base from which to argue against consumptive water use because of the way the national parks were defined [which included ecosystem protection].
The problem the Forest Service has is that the original act that created the forests, the Organic Administration Act of 1897, didn’t really say anything about qualities like ecosystems or biological diversity. It focused on flood control and water supply. So if a Forest Service unit can’t make the case that a diversion is going to alter flood control, then they don’t have a lot of basis for arguing against it.
The situation here in Colorado is not at all unique for the Intermountain West. There are a tremendous number of diversions on Forest Service Land. The typical scenario is that these start as high up in the watershed as is feasible because then you have gravity to help move the water and you have better water quality. The scenario of the “water tank” of the Rocky Mountains is not just the Colorado Front Range. It’s the whole Intermountain West. Whatever the nearest mountain range is, that’s the water tank for the urban and agricultural communities living at lower elevations. That scenario of diverting water in national forests is well established and would be very hard to change. The Forest Service has had a very hard time getting any reserved water rights.
As I learned from your essay “Poisoning the Well,” even water high up in the watershed, in seemingly pristine parks and forests, is not so perfect. I was surprised to find out how quickly that little snowflake becomes polluted by excess nitrogen in the air.
Yes. Mercury is the other big one, which scares me and really surprised me when I started looking into it too, because of the atmospheric deposition. Mercury and nitrates are two of the big airborne contaminants that we have become aware of.
Where is the mercury coming from?
Mercury is coming primarily from coal burning power plants. I was very shocked to learn of the situation in one of the wilderness areas farther to the west of the Front Range that’s downwind of a coal-fired power plant in Colorado. They have lost a lot of the amphibians in the high elevation lakes. A drop in the number of frogs and salamanders is a pretty important alarm signal that most people are not yet aware of.
One of the points I try to make in the book is that a landscape can look pretty pristine if you just step out of your car and look at it. It may be beautiful, with no houses or roads but it could have experienced major changes that are hard to detect or even invisible.
How has the diversion of water from the western slope to the Front Range impacted the plains rivers?
It’s just part of the general changes of flow regulations. I think if the water actually goes to the plains rivers it might have more of an impact, but a lot of that water never reaches the plains. It’s taken up by the Front Range urban communities at the base of the mountains. If you imagine a graph where you show flow through time over the course of a year, you’d have a big snowmelt peak and pretty low flows this time of the year. All the effects of flow diversion have been to smush the vertical axis on that so that we have a much more uniform flow through the year, and diversion from the Western Slope is part of that.
The story of what happened in the fall of 1996 of The Nature Conservancy’s Phantom Canyon Preserve along the North Fork of the Cache la Poudre River tells a great deal about the impact of water diversion on the Southern Rocky Mountain river systems and the resilience of those systems. Can you recount that story for our readers?
Phantom Canyon is a deep, narrow canyon – almost a gorge – along the river. The Nature Conservancy bought it in the late 1980s. There is a dam immediately upstream of the Conservancy’s boundaries that was built in the early 1900s for agricultural water supply. Now, the city of Ft. Collins is actually a majority stockholder in it. That dam is what’s called a “fill and spill” dam. As it’s gradually filling during the spring snowmelt, they can let out up to 140 cubic feet per second (cfs). If the reservoir fills up faster than that rate, it just spills out over the top.
The usual scenario is that they draw the water down in the dam late in the growing season (late September) so they have maximum storage capacity the following spring. Because of the way this dam was designed, they cannot bypass sediment. Newer dams have the option to flush sediment through, but this one doesn’t. For this dam, most of it accumulates in the upstream end of the reservoir, but some of it – particularly the finer sediment – gradually reaches the base of the dam. When they draw the water level down, if the water level is low, they can release some sediment.
In 1996, the North Poudre Irrigation Company, which operates the dam, released a lot of sediment during this drawdown period and then shut of the water flow completely. The effect of that was dumping a big bunch of sediment into the river and then turning off the water supply, so the sediment just stayed there. It basically filled up some very deep pools close to the dam. As you got farther from the dam, pools were partially filled. There was some evidence that they had done this in the past, but nobody was really aware of it because it’s a fairly remote area and before it was purchased by The Nature Conservancy, it was private property with much less public visibility.
When they did this, a lot of fish were killed – at least 3,000 that were counted. The Nature Conservancy brought in the Division of Wildlife. There were newspaper articles about it. People were very upset. They asked me to come in and estimate how long it might take to restore the pools, to scour the sediment and recreate the river that was there before. I really thought it would take a few years, but we were very lucky in that 1996-97 was a big snow year. We had particularly good peak runoff the following spring and early summer. About 80% of that sediment was removed and flushed downstream. The irony of the original sediment release was that if they kept the water flowing, that sediment would’ve been gradually deposited over a much longer distance downstream and it wouldn’t have been a problem. The main problem was that they released it and then stopped the water flow.
So when we had this great spring-summer snowmelt runoff, it restored a lot of the pool volume, but the system didn’t recover immediately because you have to have recolonization by everything from fish to aquatic insects and it takes a while. The system still has some problems today, a decade later, but by and large, the fish populations and aquatic insects recovered within two years, so it was pretty encouraging. From my perspective, chemical contamination can be much worse, because it can persist and you can have very toxic materials linger in sediment for decades or centuries. A physical disruption in water or sediment is much more likely to be reversible as long as organisms can have some way of getting back into the system.
After what happened at Phantom Canyon, have any regulations been put in place to prevent other companies from releasing sediment and then stopping the water flow?
In that particular case, I don’t think they will do it again. Initially, the dam operators were rather defensive, but The Nature Conservancy was very diplomatic and talked the operators around to a much more cooperative stance.
A couple of years after that, there was a Denver Water Supply reservoir that had real problems with sedimentation of organic materials and a lot of wood coming in because of a series of very severe forest fires that had occurred. Being aware of what had happened in the Phantom Canyon example, they worked actively with the Division of Wildlife to design releases of the sediment and water so that they wouldn’t kill fish downstream. It was all planned out and it worked. They released a lot of sediment and there were no fish kills.
So the bad publicity had a positive effect, but I’m not aware of any legislation that prevents [releasing sediment and then shutting off the water].
Agriculture, gold mining, recreational industries, and water diversion have been influencing Southern Rocky Mountain Bioregion (SRMB) river systems for quite a while. How are more recently acknowledged factors, such as energy sprawl, emerging contaminates, exurbia, and climate change impacting these rivers? Which of these factors has you most concerned?
They all have me concerned. It’s very site-specific for some of these. The energy development affects some rivers pretty substantially, mainly by changing the surface water-ground water relations and introducing contaminants to the groundwater, but other basins are really not affected by that. Urban sprawl is a big one everywhere. Most of the Intermountain states are subject to that.
Climate change is a big wild card. What I see climate change doing is making a tight situation tighter. Most of the predictions in the Intermountain West are for hotter and drier. As population continues to grow, there is more pressure on water resources. If those water resources are shrinking, that’s going to be a pretty severe problem. We’ve had a couple of cushions in the past for water supply. One is groundwater. But that cushion is disappearing. We’re pumping the groundwater to the point where it has dropped and it is prohibitively expensive to extract. In agricultural areas, most of the shallow groundwater is contaminated now. In the Eastern Plains of Colorado, there is very little shallow groundwater that is still suitable for urban and municipal consumption. The other cushion has been that we haven’t drawn on all of the supplies that are guaranteed to us under the Colorado River Basin Compact of 1922. It governs water use in the Intermountain West, from Colorado to Southern California and Arizona. Southern California and Arizona have, for the last decade or so, drawn their full allocations, and sometimes overdrawn it. They’ve been able to do that because some of the upper basin states like Colorado have not been withdrawing their full allocation. As our population and water use continue to grow, that stresses the whole system. The rate of population growth in the West is still increasing. If we have climate change creating less water supply, and we have more people, that’s going to be a big problem. We can easily see natural systems getting caught in the crosshairs.
In the long term, climate change is the biggest threat. In the short term, patterns of land development and the contamination associated with that are two of the biggest threats. Part of the issue with emerging contaminants is that no water supply system removes those. You can have a superb municipal water supply system, but it won’t remove things like pharmaceuticals, personal-care products and endocrine disruptors.
Tell me more about endocrine disruptors.
Endocrine disruptors are synthetic chemicals that mimic the effect of endocrines in the human system. They come from things like cosmetics and flexible plastics in margarine and yogurt tubs. Many of them mimic the effects of estrogen. They have the greatest effect on the developmental stages of organisms, including humans. A lot of very pervasive, gradual trends (like early puberty in girls) are being tied to them. There is also convincing evidence that many of these synthetic chemicals are tied to the alarming increases in all forms of cancer. There is almost no testing in terms of the environmental effects on health of humans or other organisms.
Why is that?
That’s a very good question. It’s expensive and time-consuming, so companies don’t want to do it. The standard test is to expose a laboratory organism to high doses of the chemical over a short period of time. They don’t look at what background levels would do, because that would take much longer. They don’t look at how the breakdown products of these synthetic chemicals interact with different media like water, soil and air. They don’t look at how individual chemicals interact with each other. Herbicides and pesticides are a great example that you can do toxicity studies on a single chemical in the lab, but no one looks at how the breakdown products, which are combining in the environment interact to create biohazards or ecotoxicology.
I’m afraid it comes down to economics. We have not had the regulatory climate that has forced companies to do this testing. This is way beyond what I work on, but I can recommend two authors who are really worth looking into to learn more about this: Theo Colborn, who wrote the book Our Stolen Future and Sandra Steingraber, who wrote the book Living Downstream.
Are you seeing any positive movement in the Southern Rocky Mountain Bioregion to address the short-term threat of land development and the associated contamination?
There is a proposal right now to build a very large off-channel reservoir on the Poudre, right at the base of the mountains. It is part of a larger project called “NISP,” Northern Integrated Supply Project. They also want to build a new reservoir by Greeley, which is farther out in the plains. Basically, it’s a big water diversion scheme. This is an Army Corps of Engineers project that is being “sold” as being necessary for promoting growth and development of the smaller agricultural communities by providing a water supply.
There has been a huge amount of pushback. A citizens group formed to protest the proposal, and they have been very effective. With that effort, and the changing economic situation, where some of the municipalities that were originally part of NISP have pulled out because it’s too expensive, I think there is a very good chance that the proposal will not go through.
Equally important, this citizen group is not just reacting to what they see as a detrimental project, they have been very proactive in saying, “Let’s start thinking about the Poudre River as a system, and let’s see what we can do to propose alternatives where we can have a viable plains portion of the Poudre. The mountains portion of the Poudre has a lot of impacts, but it’s still viable.” Once that river hits the plains, it’s just a trickle, and it’s really very much altered from what was present historically.
Separate from the citizens group, we have very strong and proactive open space and natural areas programs in both the City of Ft. Collins and Larimer County. They have been gradually acquiring land along the Poudre River and they have a vision of having continuous public space and natural areas from the base of the mountains out to Greeley, where Poudre River joins the South Platte River. They are going to need to get some water rights in order to do that, which is going to be harder than land acquisition, but they’re planning for that. I think this is really great. If you have a natural corridor, where people can hike, birdwatch, fish and bike, there will be a lot more public support. Right now, people (including me) tend to look west for recreation. If you have places like this along the Poudre, that are a very short drive from town, I believe there will be more appreciation for plains Rivers.
Many of the cities in Colorado have strong programs encouraging energy conservation and xeriscaping. I just installed photovoltaic panels in my house and I got a big rebate and part of that came from the City. As part of that, they did an energy audit of my house and told me other ways to save energy on natural gas heating for example. They’ll do free sprinkler audits. They have a very strong program helping people to xeriscape either portions of their yards or whole yards.
When I first moved to Colorado in 1989, I had no water meter on my house. I moved to another house in 1998, and by that time the City had mandated partial xeriscaping and low water use appliances.
So I see programs at the city and county level that are making people aware of both energy and water use and working to preserve open space and build a constituency for the local rivers like the Poudre.
In the preface to Of Rocks and Rivers, you quote renowned scientist Aldo Leopold, who said “The penalty of an ecological education is to live in a world of wounds.” You have witnessed and uncovered many of these wounds in the SRMB. Yet at the conclusion of your book, you seem optimistic. You state that the challenge is now to integrate the insights gained from research like yours into “everyday choices made by individuals and society in order to improve our collective ability to live sustainably in the American West.” In addition to open space programs and citizen activism, what are some examples of things you have seen people and organizations doing that are effecting change in a positive way?
Just changing at the very basic level, with lifestyle choices. The City of Ft. Collins really encourages bicycle commuting. That can be something as simple as having bike lanes and trails. But they also have “Bike to Work” days where local businesses donate breakfast for people who commute by bike.
I see positive changes in people becoming more aware of how their everyday actions affect the whole world around us – whether it’s the food they eat, how they use water, or how they use energy in their homes or in their transportation.
So a groundswell of changes in people’s everyday actions helps buoy you amidst the doom and gloom?
How do I maintain optimism? I have two sources. One comes from a movie I once saw about social activists. In that movie, someone asks one of the activists that question and the activist just looks in the camera and says, “What’s the alternative?”
The other comes every time I go hiking, skiing or paddling. This is worth fighting for. This is worth preserving. The natural world itself is a source of inspiration for me. I suspect anybody who is involved in any kind of activism must find that sense of renewal and purpose in seeing whatever it is they care about.
You state that your “sense of place” out West constantly changed as you continuously learned about the landscape. How would you describe the “sense of place” of the Southern Rocky Mountain Bioregion today?
I still describe my sense of place as having many of the same components it had when I first moved here. This is a place that has been used, but not as heavily as some parts of the world. In Europe, you have land use changes that go back to the Bronze Age! So there is still a sense of a natural landscape, where it is easy to get away from large numbers of people. There is a sense of openness that is partly a function of climate – the aridity and relatively sparse vegetation. Because of the lack of human alteration of the landscape relative to other parts of the world, there is still that sense of being close to natural processes. You can see evidence of geology – the mountain building or valley cutting of glaciers.
To summarize, it’s still a very similar sense of place that I had when I moved here. It’s just tempered by that knowledge that it is not as apart from humans as I once thought it was. There is a longer and more intensive history of human interaction with the landscape than I was aware of.
Some of your essays include very strong calls to action. In “Poisoning the Well” you state that “Historical changes along the plains rivers that have so stressed wildlife communities need to be reversed to some extent in order to ease the pressure on threatened and endangered species.” Are people heeding this call to action? If so, who is and what is being done?
Because the great majority of our endangered fish species are in the plains rivers, the government agencies that are most tied to that issue, such as the Division of Wildlife and the Forest Service, have taken action. They have undertaken programs both to identify the distribution of these species and protect specific locations where they occur. They have also tried active restocking.
I’ll give you a specific example. All of the endangered fish species on the plains are very small bodied species – we’re talking a couple of inches long. That’s one of the ways to survive in that very physically stressful environment. Most of their lives are spent in what fisheries biologists called ‘refuge pools,’ isolated areas that retain water throughout the year because they intersect the water table. Periodically, when you have a lot of flow, there will be surface water flowing between those refuge pools, so the fish can move out, breathe and disperse. Then, they come back to refuge pools for the rest of the year. One of the actions [the Forest Service has] undertaken on the Pawnee National Grassland is yearly surveys of where these fish are, where the pools are, and how many fish are in them. They have restocked and transplanted some of the fish to create more widely scattered populations. They have fenced off some of the pools to limit cattle grazing. (Primary uses on the Pawnee are cattle grazing and, more recently, energy development.) They have undertaken programs to identify and protect some of these species.
But the Plains in particular are almost off the public radar screen. If you talk about endangered fish in Colorado, people are not going to think of the Plains. They’re going to think about trout in the mountains. Part of what we need to do is raise public awareness of the real beauty and unique aspects of these Plains Rivers. That’s something I’m going to do with Wide Rivers Crossed, a book I wrote that is currently in review at University of Chicago Press. This book looks at historical changes in rivers of the prairies. I use the Illinois River as an example in the Eastern Prairies and the South Platte River as an example in the Western Prairies.
Any key insights from that book that you’d like to share with people at this point?
People tend to fly over, drive across, or do whatever they can to ignore the prairies, yet they are the most endangered ecosystem in our country. There is almost nothing of the tall grass prairie left and more than half of the short grass prairies have been substantially altered.
I got interested in prairies because I live near a little natural area in town that is a short grass prairie. I take walks out there frequently, and I started seeing a lot of life. It’s not just a big, empty field of grass. There’s a lot going on out there. I really became fascinated with prairie ecology.
What else are you currently working on?
I have a book in press at the University of Chicago that I have been working on for seven years. It’s called A World of Rivers, and it looks at environmental change on 10 of the world’s major rivers: the Amazon, the Congo, etc. That book will come out in 2010.
Are there any other parts of the world that are similar in some way to the Southern Rocky Mountain Bioregion and can offer some insight regarding potential solutions to today’s mounting ecological problems? (Conversely, what can other regions or nations learn from what has happened to the SRMB landscape?)
The details of [a region’s] history differ, but the whole idea that multiple land uses occurring through time have a cumulative effect of reducing the diversity and stability of rivers and natural systems…unfortunately, that applies anywhere in the world.
We could learn from lessons from Europe, in terms of sustainability, because there are some places there where they have been able to maintain agricultural societies for many centuries. Jared Diamond makes a good point in Collapse: How Societies Choose to Fail or Succeed. He gives lots of examples of societies that collapsed because they couldn’t maintain their rate of resource use. But he also gives examples of those that didn’t.
Being more specific, many of the issues that are raised for the Southern Rocky Mountains would apply to the entire Intermountain West. The scarcity of water is the big issue for the Intermountain West, as it is for any arid or semi-arid region.
What could other regions learn from what has happened here? That we need to take a less anthropocentric view of resource use, including water.
Any final words of advice/wisdom to offer Leaf Litter readers? (Any specific messages you hope they take away from the work you have done?)
I’d like people to think carefully about the slogan of “you deserve it.” This slogan is often used in advertising to get you to purchase a product because you deserve it. We’re so used to indulging ourselves and not thinking of long-term consequences. But everything we do has consequences for the natural world. If you care about that, and if you care about the sustainability of human populations, you need to be aware that we live in a very complexly interwoven environment. Basically, everything you do affects rivers, so think carefully about what you do!