Kitimo, A., Mwaniki, C., & Wasuna, B. (2020, March 8). LENTANA: Dams are the next frontier in taming destructive floods. Retrieved March 5, 2020, from https://www.businessdailyafrica.com/analysis/columnists/Dams-are-the-next-frontier-in-taming-destructive-floods/4259356-5483106-qwx5m6z/index.html 

There is a lot of water insecurity in Kenya, with a severe lack of water most of the year and extreme floods during a few months. These floods cost human life and property, and more dams would reduce the number of floods to basically zero. Dams would also reserve water that would otherwise gush into the ocean. This would release farmers from reliance on rain-fed agriculture, therefor helping food production. Also, water would be available year round, regardless of the time of year. Dams would need monitoring to prevent collapse and siltation, but the advantages make dams worth it. 

This article highlights the powerful role that dams can play in protecting people from the uncertainty of natural events like draught and flooding. The fact that dams could save peoples’ lives by preventing flooding is an incredibly compelling argument for installing them. It is difficult to even consider the environmental damage that dams might cause while knowing that they could save lives. At the same time, I do wonder what the tradeoffs of installing more dams in Kenya would be. If the plants in the region have evolved to deal with dry seasons followed by flooding, they could be negatively affected by a lack of floods. I think more research should be done on the potential environmental drawbacks of creating new dams so that the drawbacks can be more clearly understood and considered.

Elbein, A. (2020, February 21). Past and future tropical dams devastating to fish the world over: Study. Retrieved March 7, 2020, from https://news.mongabay.com/2020/02/past-and-future-tropical-dams-devastating-to-fish-the-world-over-study/ 

Dam construction will increase habitat fragmentation along rivers like the Amazon, Niger, Congo, Salween and Mekong by a quarter or more. Based on data from 10,000 fish species, 40,000 dams, and 3,700 dams planned for the future, scientists have concluded that habitat fragmentation might be as high as 40% on average. Dams block fish migrations which reduces the reproduction of these species and breaks populations into isolated groups. Dams can also have an opposite effect, with fish ladders aiding non-native species in bypassing natural barriers such as river rapids removed by dams. Also ecologically detrimental: dams convert formerly fast moving streams into still-water reservoirs, with the water at the bottom becoming oxygen-poor, potentially wiping out bottom-dwellers. Dams trap sediments in their reservoirs, thus reducing nutrient content and fish production in the downstream river stretches.

This relates to environmental science as it shows the impact of dams on biodiversity. The research done in the article is important because understanding dams’ effect on habitat fragmentation is necessary to quantify the ecological tradeoffs associated with building dams. It is also important to note that species losses also affects people who depend on fish for their livelihood or as a food source. Knowing about the impacts of dams can have could help people place dams in places that where they won’t have as much of an effect on the environment. I think that even with the environmental drawbacks, it could be worth having dams in certain places because of the electricity they could produce.

Pflüger, F. (2020, February 11). A new security challenge: The geopolitical implications of climate change. Retrieved March 4, 2020, from https://www.atlanticcouncil.org/blogs/energysource/a-new-security-challenge-the-geopolitical-implications-of-climate-change/ 

Water management has been a source of disputes in Asia between upstream countries (Kyrgyzstan & Tajikistan) and downstream states (Kazakhstan, Turkmenistan, & Uzbekistan). Kyrgyzstan and Tajikistan hope to construct dams to meet their energy needs. However, dam building threatens to limit the water supply for the downstream countries. China is constructing dams on the Brahmaputra River, which is a major water source feeding rivers that flow into both India and Bangladesh. These projects will give Beijing more control over the quantity and quality of water flowing downstream. India has also been constructing dams, and, in 2019, threatened to cut off some of the Ravi River’s water that flows into Pakistan. The Tigris and Euphrates rivers account for 98% of Iraqi water supply. Turkey and Iran have used their upstream position to build dams to meet their own water needs. Dams on the Euphrates River have reduced water flow into Iraq by 80% over the past forty years.  

This article relates to environmental science as it shows how an element of nature (water) affects relationships between countries. Dams can give a country lots of control over a body of water, which can be a source of conflict when another country depends on that water source too. I think as climate change continues to limit water supply in some places, the risk for conflict over water will increase. This might encourage countries to build more dams in order to guarantee a more stable water supply which could in turn incite additional political strife. Dams have the potential to be a powerful weapon as they allow one place to limit another country’s water supply. The power of dams will certainly be amplified during times of drought, and increasing water scarcity might spark more conflicts over water supply in the future.

McQuate, S. (2020, February 14). Hydropower dams cool rivers in the Mekong River basin, satellites show. Retrieved March 6, 2020, from https://www.sciencedaily.com/releases/2020/02/200214134657.htm 

Researchers studied dams along three rivers Southeast Asia’s Mekong River basin, and discovered that within one year of the opening of a major dam, downstream river temperatures during the dry season dropped ~3.6 ºF. The three rivers converge into the Mekong River. This infusion once warmed the Mekong so that the river was slightly warmer downstream of than upstream. But after dams were built, the trend reversed and temperatures dropped  ~1.5ºF. Before 2009, all three rivers had a similar temperature pattern: the water warmed in the dry season, then cooled during the wet season. But after dams were built, the Sesan and the Srepok rivers stayed cool year-round. After a dam is installed, there is more water in the dry season and less water in the wet season. The dry-season water is also colder because it’s pulled from deep within the reservoir. That brings the temperature down closer to what it is in the wet season.

This article relates to environmental science as it shows the effect that dams can have on the environment. I think it’s really interesting that the cooling effect scientists noticed isn’t localized round the dam but is affecting the entire river system. This data highlights how disruptive dams are to ecosystems. However, just because these dams are affecting the water temperature doesn’t mean that installing dams is always a bad idea since they do provide clean energy. The effect dams have on temperature is just another aspect that people need to consider when they decide if installing a dam is worth the environmental drawbacks. Even if temperatures in rivers drop just a few degrees, this can still have a big impact on aquatic life. It’s great that scientists are tracking the effects of dams, as the data they collect can give people a more accurate understanding of the pros and cons of dams.

Opperman, J. (2019, July 16). Remove A Dam And Bend The Curve For Fish. Retrieved November 11, 2019, from https://www.forbes.com/sites/jeffopperman/2019/07/16/remove-a-dam-and-bend-the-curve-for-fish/#68ed79e84b68. 

Fish populations have been decreasing with an 83% decline in freshwater-dependent species (according to the Living Planet Index).  For 50 years, that Index has shown a consistent downward curve. However, removing a dam can help change this. After dam removal on the Penobscot, the amount of river herring increased from a few thousand to over two million. Changes in renewable energy – like the deployment of wind and solar – along with various innovative solutions, is setting the stage for increasing fish populations. Many dams in the US are being removed because they are old and unsafe. Small barriers can be removed for a relatively low cost. Oftentimes, for a tiny loss in electricity production, dams can be changed to dramatically help fish. For example, a study for the Willamette River basin found that removing 12 out of 150 dams would reconnect 52% of the drainage basin to the ocean — key for restoring salmon habitat — with a loss of less than 2% of the basin’s hydropower generation. 

This article has a more hopeful tone in regard to the future. The idea that by removing dams, people truly make a huge difference for animals is inspiring. The focus on innovation is important as it shows that not all solutions depend on technology: some just need some clever thinking. Evaluating which dams have the largest impact on the environment allows people to remove the dams that harm the environment the most and produce the least electricity. While not all dams need, or should, be destroyed, getting rid of some can help endangered species recover. There are clearly environmental benefits to destroying dams, but there are also some environmental costs to destroying them. For one, waste is created from the old dam, also it takes energy to destroy something so massive, and that electricity is probably coming from fossil fuels. 

23, T. C. P. O. (2019, October 23). In Our View: Removing dams would damn N.W. economy. Retrieved November 11, 2019, from https://www.columbian.com/news/2019/oct/23/in-our-view-removing-dams-would-damn-n-w-economy/.               

Dams provide inexpensive, reliable, clean, and renewable electricity. However, many protest them. Recently, Native American tribes have called for the removal of three Columbia River dams — Bonneville, The Dalles and John Day. They hope the removal of these dams would support salmon recovery and help dwindling populations of orcas that rely on salmon for food. These are valid concerns, but destroying dams would require the construction of additional power plants fueled by natural gas or coal or nuclear energy. It will take time to develop more wind and solar energy. Dams throughout the Northwest have been environmentally imperfect as they have played a role in diminishing salmon runs. But removal would be a radical step that would hurt the economy of the entire region. A balanced and incremental approach is needed. 

The article focusses on the connection between the economy and the environment. If dams were to be destroyed, jobs and money would be destroyed along with them. I believe that many dams should be removed, just not all at once. As dams age, it will stop being economically smart to remove them anyway because of mounting costs for repairs. When dams reach a point where extensive work is needed then they should simply be removed. However, this should be a slow process because, as this article mentions, just removing all dams would hurt the economy. Also, dams provide for a smoother transition into green energy sources. While scientists continue to advance solar and wind energy, dams provide a solid energy base. This relates to environmental science because the way we get energy significantly impacts ecosystems on Earth. For example, burning fossil fuels leads to climate change which negatively impacts many animals. 

Fitzner, Z. (2019, October 21). Does it make sense to replace America’s aging dams with solar panels? • Earth.com. Retrieved November 11, 2019, from https://www.earth.com/news/replace-dams-solar-panels/. 

Silt builds up behind dams, and the water is warmer in a reservoir than in the original river. This leads to a release of methane and a loss of biodiversity. As the original life drowned by flooding decay, carbon dioxide is released. As dams get older, they are requiring more maintenance, and many are being removed because of this. Solar electricity could potentially replace the lost electricity from hydroelectric. If all hydroelectric dams were removed and only half of the land area they occupied was replaced with solar, it could generate 3.44 times the amount of electricity currently created by hydroelectric. However, there are some downsides to solar: it isn’t produced all day, varies per season, and varies by location. Also, due to the carbon footprint of producing a solar panel, solar produces more carbon on average over its lifetime than hydro. There are also problems related to disposing solar panels. By 2050 there will be an estimated 60 to 78 million tons of solar panel waste.      

I hadn’t thought about the environmental cost of producing solar panels. This shows me that there is no perfect clean energy solution as all options have drawbacks. I had not considered the fact that dams lead to the release of carbon dioxide. The fact that dams even alter the temperature of the water shows what a powerful impact they have on the environment. The best clean energy type probably differs from region to region. This shows that even when people try and protect the environment, there can be unintended consequences. Although technology is usually associated with an increase in environmental damage and pollution, here, new technological developments could actually help the environment by making solar panels more sustainable.                

Kilvert, N. (2019, October 30). Dams benefit big irrigators, but cost communities, taxpayers, and the environment. Retrieved November 11, 2019, from https://www.abc.net.au/news/science/2019-10-30/dams-irrigators-drought-environment/11585470.

Throughout the US, overfishing is devastating local fish populations, dams are changing the natural landscape, and the water levels in many lakes are dropping. Water levels drop largely because people get permits to take large amounts of water out of the lakes and then they go on to take even more than they are allowed to. Dams that stop rivers from flowing into the sea can be especially harmful. When fresh water doesn’t flow out to the sea/bay, the marine environment starts to push its way up river (this is called a salt wedge).  Most dams don’t make economic sense, and only benefit a few big irrigators at the expense of the taxpayer, according to Professor Grafton. The problem, according to Professor Grafton, is that building new dams creates more demand. When more water is available, it is quickly allocated as irrigators increase their usage or bigger operators move in. And once we increase demand and dependence on a system, it’s very difficult to turn back.

This article demonstrates the connection between environment and economy. In general, things are good for economy seem to hurt the environment. The idea that the supply of dams create a demand for dams is interesting. In The Omnivore’s Dilemma, Pollan states that the same thing is true for corn – the supply creates a demand. This is bad because when there is too much of something (either water or corn) this pushes people to use more of it until they depend on having more of that resource. It is saddening to think of all the negative effects dams have on the environment. When you just think about them as a water supply, it really doesn’t seem worth it. However, dams are also an excellent source of clean energy, so it is important to see both the drawbacks and positives of dams.  

Fugate Press, C. (2019, November 11). At least 1,680 dams across the US pose potential risk. Retrieved November 11, 2019, from https://nypost.com/2019/11/11/at-least-1680-dams-across-the-us-pose-potential-risk/.

Recently both the Lake Dunlap Dam and Spencer dams both broke, leading to deaths and property damage. An investigation by The Associated Press has found scores of dams nationwide in even worse condition, and in equally dangerous locations. They are near homes, businesses, highways or entire communities that could face life-threatening floods if the dams don’t hold. about 1,000 dams have failed over the past four decades. The nation’s dams are over a half-century old on average. Some are no longer adequate to handle the intense rainfall and floods of a changing climate. A National Climate Assessment released by the White House last year noted growing frequency and intensity of storms as the climate changes. That can push some dams beyond what they were designed to handle.

It is interesting that climate change is contributing to dam failures. This is somewhat of a positive feedback loop because, when dams fail, the towns they destroy need to be repaired which demands the use of more materials and fossil fuels. This also related to environmental science, because when dams fail, the water carries out pollutants in cities out into surrounding ecosystems and into local bodies of water. This is an instance where something (in this case dams) pose a threat to both humans and the environment. The dangers dams pose to human lives is just another reason why people should consider destroying some of the older dams. This is a good example of how climate change can negatively affect humans. Global warming, caused by the burning of fossil fuels, leads to biggers storms, which in turn hurts dams. Another problem with dams becoming older and less secure is that it takes lots of money to continuously repair and maintain them. It would, of course, also take money to tear the dams down. The expenses related to dams seem like the main reason that people are slow to react to the dangers posed by them.

(2019, May 14). Shasta Dam Project Sets Up Another Trump-California Showdown. Retrieved August 24, 2019 from https://www.kqed.org/science/1937108/shasta-dam-project-sets-up-another-trump-california-showdown 

The Trump administration is planning to enlarge California’s Shasta Dam by raising its height, which violates the state’s Wild & Scenic Rivers Act. This act protects one of the rivers that flows into Shasta Reservoir. Caleen Sisk, chief of the Winnemem Wintutribe, says almost all of the tribe’s sacred sites would be end up underwater with the reservoir’s expansion. The expansion would also further impair salmon runs downstream. A meeting about the project was run by Westlands Water District, an irrigation district. Many assume that Westlands will pay millions of dollars for the project, in exchange for rights to the water it yields. This would be illegal under state law. However, Bader, the area manager for the reclamation bureau, has threatened to “move forward by getting the federal approval.” But, Democrats (who control the House) might cut off congressional funding. On May 14, 2019 (three months after this story first appeared), California and various fishing and conservation groups sued to stop Westlands Water District from expanding the dam.

It is interesting to see the political side to dam construction. It is disheartening to see that the Westland Water District is not listening to people’s worries about dam expansion. I think the Westland Water District is in denial about the negative effects of dams, and is instead just focussed on how they can benefit. This relates to environmental science because the outcome of the debate over the Shasta Dam expansion project will no doubt impact the surrounding environment. Dams are important because they allow us to save water, but this article demonstrates the side effects of them. Both the Native American sites that would be lost and the impact on salmon migration makes me feel that raising the dam is not worth the cost. Instead of spending money on increasing the size of the dam, I think the government should spend that money on stormwater capture or storing more water in underground aquifers. These options provide an alternative option to increasing dam size, while still collecting water.