Are dams a good or bad idea?
Dams continue to be built in areas of Asia, Africa and South America. Yet, they are being torn down in other parts of the world like in western Europe and the USA.
This makes us question are dams a good or bad idea? Dams are a prime example of the way in which we can control nature to produce renewable energy. However, while they are beneficial for producing renewable energy, they also drastically alter the natural life of rivers and harm their ecosystems. This leaves a choice to be made between energy production and biodiversity.
Hydro electricity is a significant source of low carbon energy for many countries. Dams can also allow for a regular water supply and help to reduce flooding. They can also be a tool used in economic development.
Dams severely transform a river’s natural course. Along with this can come changes for those who live nearby. Destruction of homes, farmland and livelihoods can occur with the creation of a dam. For example, an ancient town in Turkey was lost to rising reservoir water.
Hasankeyf was a 12,000-year-old village and was known as an ‘archaeological gem’ which is now submerged under the rising water of the Ilisu Dam. This has led to the displacement of 70,000 people. Unexplored archaeological treasures have been drowned along with farmland and homes.
President Recep Tayyip Erdogan’s stated the dam would contribute billions to the economy and irrigate thousands of hectares of farmland in the impoverished and insurgency-riven southeast. The move to a greener source of energy through hydropower is also hoped to lead to less dependence on imported coal and gas. Syria and Iraq argue that Turkey could deprive them of much needed water.
Grand Ethiopian Renaissance Dam
Another complicated dam would the Grand Ethiopian Renaissance Dam. This has been a contentious issue between Ethiopia and Egypt, with Sudan caught in the midst of it. It will be the largest hydroelectric power plant in Africa.
Egypt fears that the project will enable Ethiopia to control the flow of the Nile. Egypt relies on the Nile for 90% of its water. The speed with which Ethiopia’s fills up the dam’s reservoir will affect the flow downstream. The longer it takes to fill the reservoir, the less impact it has on the level of the river. Ethiopia want to fill it in six years while Egypt suggested a longer period. Ethiopia wants this large dam to provide its citizens with electricity, of which 65% are not connected to the grid. They could also sell the surplus to neighbouring countries like Sudan, South Sudan, Kenya, Djibouti and Eritrea. They are likely to benefit from the power produced by the dam.
There have been fears of a water war between the countries. The reservoir is larger than Greater London and have the capacity to hold 73 billion cubic metres of water.
Why remove them?
So, while these huge dams are being built despite major political, social and environmental complications, why are other countries tearing down dams? For example, two large hydroelectric dams are being removed on the River Sélune in Normandy. This is the biggest dam removal project in Europe to date.
The US has also begun tearing down some of its dams. There has been a change in how we think about dams. People have begun to evaluate which ones still make sense and we have entered into an era that views dams as infrastructure that has a finite lifetime. It makes sense to remove dams that have the least economic value and the most ecological impact. There are approximately 91,000 dams in the United States that vary in size and purpose. Many of the rivers in the US have dams that were part of the industrial revolution. At least half are said to be not serving a useful purpose anymore.
Dams alter habitats in rivers. Fish and other aquatic animals need to be able to move so they can find new food sources or avoid predation and dams prevent this. Dams can also degrade water quality. These aspects are critical for the survival of species that live in the river.
David R. Montgomery, Professor of Earth and Space Sciences from the University of Washington, describes a river as the circulatory system of a landscape.
However, people still see dams as a vital source of energy and enjoy the lakes and recreational aspects they offer. So how do you please everyone? Serena McClane, Director of River Restoration at American Rivers, takes the approach that if a dam is serving a purpose and has a function that benefits greater society it is up to us to manage that dam in a way to enhance the environment in the most effective way possible.
One of the world’s largest dam removals involved two large dams on the Elwha river, northern Washington state. They were dismantled which resulted in a restored habitat for wildlife and fish. This led to the reclamation of 75% of previously inaccessible spawning habitat. The sediment that had been trapped behind the dam has washed downstream which has created some 70 acres of new habitat for Dungeness crabs, sand lance, surf smelt, clams, and other species. The dam detrimentally impacted the Lower Elwha Klallam tribe who reside near the mouth of the Elwha.
They hopewith the removal of the dam its members will be able to harvest shellfish close to the mouth of the Elwha. The dams devasted the livelihood of the Elwha Klallam people.
Fishing, as a livelihood, has also been extremely important to the Yurok people who are California’s largest indigenous group. They have lived for millennia in rural northern California. Their livelihood has been threatened for decades by the damming of the Klamath river for hydroelectricity. The spring run- Chinook salmon, which had numbered in the hundreds and thousands dropped to fewer than 700 last year. The dams built on the Klamath river have been tied to these changes in salmon populations on the Klamath and elsewhere. The Klamath’s lowest dam, the Iron Gate, has created an overcrowded environment which is a breeding ground for the parasite C.Shasta which juvenile chinook salmon are vulnerable to. The reservoirs behind the dam have also experienced a build-up of toxic algae. This not only impacts fishing but also Yurok culture.
Frankie Myers, vice-chairman of the Yurok tribe states, “There are pieces of our culture and our spiritual practices that we cannot do now without risking the health and safety of our people,” he explains. “The place we go to pray, the place we go to heal, the place we go to do our medicine will make you sick. That has a psychological impact on our communities.”
However, things are set to improve for the Yurok people as the go ahead has been given for the largest dam removal project in the US.
Dams and hydropower are valued by many people as we have seen through the examples in Ethiopia and Turkey, despite the societal and environmental damage. They are still a significant source of energy for many countries. Richard Taylor, chief executive of the International Hydropower Association, states managing freshwater is probably one of the biggest challenges that humanity has this century. There is a clear need for balance between eco systems and hydropower. The local people that are directly affected by the creation or removal of a dam need to be included in the decision of these changes as they seemingly get rarely considered or consulted.
Grand Ethiopian Renaissance Dam
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