What Do We Need to Know About Dams?

What do we need to know about dams? This article will discuss the history and current environmental impacts of structures designed for the purpose of water impoundment. Read on for information on Fish migration, Reservoirs, and Hydroelectric power. In addition, we will discuss how dams can help manage water resources and how they can help us maintain our natural resources. But first, let’s start with the basics.


While dams and reservoirs are often constructed for various purposes, their ecological effects may be overlooked. Reservoirs and their catchments can increase or decrease CH4 emissions and other greenhouse gases. This is due to the release of nutrients from flooded land, which encourages algae and invertebrates to flourish. These increased nutrients, in turn, stimulate fish production. Adaptive capacity of reservoirs and dams may vary depending on how they are constructed and managed.

The classification of reservoirs is based on their location in a river system. Reservoirs created by damming a pre-existing lake or river will fall into the storage or run-of-river category. In contrast, reservoirs created outside the river system may be run-of-river or farm ponds. A key difference between these types of lakes and reservoirs is that storage reservoirs often have greater CA and longer residence times.

A reservoir can be divided into three zones based on their function in ecosystems. The lacustrine zone, in particular, has lower water velocities and more pronounced thermal stratification. This zone is similar to a lake, but has more similarities and distinct characteristics. In terms of ecosystem functioning, the lacustrine zone is similar to that of a lake, but its nutrient limitation is greater.

Human-mediated processes of E and m are important topics for further research, and this is especially true of reservoir ecosystems. Moreover, dams are built to address the needs of a region. Some regions, for example, do not have adequate water for human and animal consumption. Similarly, many regions lack water for agriculture. Dams help address these problems by providing both. Furthermore, they help generate hydroelectricity, which is a major contributor to general growth in a region.

Hydroelectric power

A dam can be a useful source of hydroelectric power. The water stored behind it rises in elevation and is led through large pipes and tunnels to a powerhouse. The difference in elevation between the two is known as the working head. The amount of potential power derived from water depends on the working head of the dam. The higher the head, the more water can be stored. The powerhouse is often built on one of the flanks of the dam, with the spillway portion used during floods. Sometimes the powerhouse is situated within a steep gorge.

Despite its environmental and economic benefits, hydro-electric power from dams has also led to a massive increase in debt for small countries. Today, 57,000 large dams dot the world, and more could be built. GND advocates need to clarify their support for further dam construction and demand a moratorium on dam construction. Those who support the GND should be careful not to make promises that could be construed as hollow slogans.

Large hydroelectric plants are responsible for most of the hydroelectricity produced in the United States. Washington state, for example, receives more than two-thirds of its electricity from water-fueled power plants. However, hydropower can have negative consequences, especially when the rivers are dry. Dams can cause flooding and lead to water shortages. Furthermore, the electrical current used by hydroelectric plants is relatively low, which makes them more efficient than other forms of power generation.

Building a just hydropower sector is crucial to ensuring a sustainable future. Hydrokinetic projects must be built in such a way that local populations are compensated for negative impacts, such as the deforestation, soil erosion, and heavy transmission losses. Institutions that encourage this development will help reduce transaction costs and ensure a more equitable future for all. This is crucial for the long-term health of the country, and it will be vital to the future of the nation.

Fish migration

The relationship between dams and fish migration has long been debated. There is a strong relationship between smolt development, environmental conditions, and dams. For example, fish that migrate upstream to spawn must traverse turbulent fluvial environments in order to conserve energy. Therefore, fish must relate the work done during migration to the energetic cost of swimming drag. Because this energy cost varies with the relative velocity integrated along the path, dams can alter the rate of fish migration.

The mainstream Mekong is the corridor for most long-distance migrations. Most of the Mekong’s fish production is derived from the floodplains in the lower and middle parts of the basin. Dams built on the mainstream will have greater impacts on fish production than those constructed on tributaries. In addition, dams located at these locations will disrupt the life cycle of fish. However, these factors do not explain why tributaries should be the first priority of dam construction in the LMB.

The aging penobscot River, for example, has been blocked by three dams in Maine. Because the river is so long and wide, the two million alewives that migrate up the river annually will never be able to reach their breeding grounds. Despite these challenges, the penobscot river is a prime example of a complex and multi-faceted relationship between dams and fish migration. Historically, the river was one of New England’s largest and longest rivers, but dams made it too difficult for them to migrate.

Because dams affect fish habitats, fish must find a way around them to migrate to another part of the river. Despite the widespread use of fish passes, little research has been conducted on how they perform in tropical rivers. Existing fish passage technologies largely focus on European and North American rivers. Fish-passage devices include louvers and spillway passages. Furthermore, surface collectors can transport fish past the dam. The combination of dams and fish migration must be carefully coordinated to ensure success.

Environmental impacts

The construction of dams has many negative environmental impacts. The reservoir itself submerges the area’s natural ecosystems and kills animals and plants. The vegetation at the reservoir’s bottom uses the dissolved oxygen to survive, until the resources run out and the area is rendered anaerobic. These negative effects are exacerbated if there is an unplanned reservoir spillover. Listed below are the environmental impacts of dams:

Mosquitoes breed in reservoirs, which cause mosquitoes to carry diseases like malaria, filaria, and schistosomiasis. Snails carry schistosomiasis and can also be harmful to human settlements. While many of these negative environmental impacts of dam construction cannot be remedied, some measures are taken to assist fish to migrate upstream. Here are some of the most common negative environmental impacts of dams:

The dams also negatively impact downstream habitats, which are home to numerous species. The dams alter the water’s temperature, oxygen content, and pressure, affecting the species and ecosystem. They can disrupt the ecological continuity of the waterway and adversely impact fish migration to breeding grounds. The construction process itself may endanger species, including invasive and threatened species. But even if dams aren’t directly responsible for all of these negative impacts, they still have positive effects.

In addition to the destruction of ecosystems, dam construction also has adverse effects on ocean carbon sinks. Since the Congo River water flows deep into the Atlantic Ocean, this water contributes to the growth of algae in the water’s lower levels. As sediments and nutrients disappear, these conditions for algae to store carbon dioxide become more difficult to maintain. Furthermore, dams displace an estimated 80 million people globally, many of whom are already suffering from climate change.

Social impact

The social cost of hydropower is well documented, and this applies to all dams. According to McCully, about 30 million people have been displaced by dam construction. Many of these displaced people are poor, indigenous, and leave behind productive farms and ancestral homes. Opponents of dam construction argue that “outstees” are merely paying the costs of the dam and that the benefits of the dams go to the urban areas. This is simply not true.

Although the economic and social impacts of mega-dams are often studied, the majority of these studies focus on cost-benefit analysis and do not consider local community perceptions. These community perceptions are crucial to the evaluation of the dams’ benefits and their impact on community well-being. Major socio-economic impacts of mega-dams include displacement and relocation of communities, damages to their means of support, and loss of revenue. The negative effects on the economy and well-being of communities affected by dams should not be underestimated, nor should they be dismissed.

One of the most important aspects of dams is the social impact of the dams on local communities. The creation of these mega-dams has both positive and negative effects on local communities. While some dams create a positive environment for business, others have a negative effect on local communities. While dam construction is a necessity for water supply, it can have significant social consequences. This means communities must be adequately prepared to cope with the economic and social consequences of dam construction.

Despite the positive impact of large dams on the environment and society, there are also negative effects on communities near them. Public health has often focused on the negative impacts of large dams, which include water security, food security, and communicable diseases. Furthermore, communities living near large dams do not benefit from the electricity produced by the dams. They are often directly affected by the dams, not the communities that built them.