Causes and consequences of degradation of river ecosystem in BD

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Definition of River: a natural flow of water that continues in a long line across land to the sea (Oxford
Learners Dictionary). A river is a ribbon-like body of water that flows downhill from the force of gravity.
A river can be wide and deep, or shallow enough for a person to wade across. A flowing body of water that
is smaller than a river is called a stream, creek, or brook. All rivers have a starting point where water begins
its flow (National Geographic Society, 2019)
-A wide, natural stream of fresh water that flows into an ocean or other large body of water and is usually
fed by smaller streams----river
Discuss with examples various causes and consequences of degradation of river ecosystems in BD
Increasing pop pressure and expansion of human settlements: water quality is worst in highly populated
areas, average in medium populated areas and less serious in less populated areas. Further, population
density as a major factor that should be well controlled to overcome the rapid deterioration and degradation
of the water ecosystem. With a population of over 15 million Dhaka is one of the most congested cities of
the world. This rapidly growing city is located on the northern bank of the river Buriganga and surrounded
by other rivers, namely, the Turag to the west, the Tongi Khal to the north and the Balu to the east. The
rivers surrounding Dhaka are an advantage to it and essential for the survival of the mega city as these
provide drainage system, drinking water, different kinds of fishes and also waterways for traveling.
However, being the capital of Bangladesh -- one of the poorest and least developed countries in the world,
the city has been developed haphazardly without considering its physical and social diminution. As a result,
the environmental consequences originating from rapid increase of population along with the increase of
polluting effluents from industries, and municipal as well as other waste are having profound negative
impacts on rivers around Dhaka city. In turn, the polluted waters of the rivers are posing increasing threats
to the living organisms including humans residing by the rivers.
Poverty that leads to over-exploitation of resources; Since the poor depend more critically on natural
resources-based activities in agriculture and allied sectors, they are often seen as causes as well as victims
of environmental degradation. Similarly, there are a large number of situations where the non-poor are the
major cause of environmental degradation. Intensive exploitation of ground water also causes serious
threat to living species by the decline of ground water, subsidence, attenuation and drying of springs,
decrease of river flow, and increased pollution vulnerability, among others processes.
Commercial and over-harvesting of fishery stock by the leaseholders: In addition to harvesting large
amounts of fish and seafood to sell, large-scale fishing operations catch and often unintentionally kill
untargeted marine life, including juvenile fish, corals and other bottom-feeding organisms, sharks, whales,
sea turtles, and birds. Over-fishing can result in the over-exploitation of marine ecosystem services. Fishing
can cause several negative physiological and psychological effects for fish populations including: increased
stress levels and bodily injuries resulting from lodged fish hooks. Overharvesting, or overfishing in the case
of fish and marine invertebrates, depletes some species to very low numbers and drives others to extinction.
In practical terms, it reduces valuable living resources to such low levels that their exploitation is no longer
sustainable.
Expansion-of-agricultural-activities: Agricultural practices may also have negative impacts on water
quality. Improper agricultural methods may elevate concentrations of nutrients, fecal coliforms, and
sediment loads. Increased nutrient loading from animal waste can lead to eutrophication of water bodies
which may eventually damage aquatic ecosystems. Excessive irrigation can affect water quality by causing
erosion, transporting nutrients, pesticides, and heavy metals, or decreasing the amount of water that flows

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naturally in streams and rivers. It can also cause a buildup of selenium, a toxic metal that can harm
waterfowl reproduction.
Pollution due to agro-chemicals: Chemicals and heavy metals from industrial and municipal wastewater
contaminate waterways as well. These contaminants are toxic to aquatic life—most often reducing an
organism's life span and ability to reproduce—and make their way up the food chain as predator eats prey.
In order to protect their crops from bacteria and insects, farmers often use chemicals and pesticides. When
these substances seep into the groundwater, they can harm animals, plants and humans. Additionally, when
it rains, the chemicals mix with rainwater, which then flows into rivers and streams that filter into the ocean,
causing further water pollution.
Radioactive Waste: Radioactive waste from facilities that create nuclear energy can be extremely
hazardous to the environment and must be disposed of properly. This is because uranium, the element used
in the creation of nuclear energy, is a highly toxic chemical.
Unfortunately, accidents still occur at these facilities, and toxic waste is released into the environment. The
coal and gas industries are, in many ways, no better. This is one of the major impetuses behind the
development of alternative, clean sources of energy, including solar and wind
Global Warming: Rising temperatures due to global warming are a major concern in terms of water
pollution. Global warming causes water temperatures to rise, which can kill water-dwelling animals. When
large die-offs occur, it further pollutes the water supply, exacerbating the issue.
Sewage and Wastewater: Harmful chemicals, bacteria and pathogens can be found in sewage and
wastewater even when it’s been treated. Sewage and wastewater from each household is released into the
sea with fresh water. The pathogens and bacteria found in that wastewater breed disease, and therefore are
a cause of health-related issues in humans and animals alike.
Industrial Waste: Industries and industrial sites across the world are a major contributor to water pollution.
Many industrial sites produce waste in the form of toxic chemicals and pollutants, and though regulated,
some still do not have proper waste management systems in place. In those rare cases, industrial waste is
dumped into nearby freshwater systems. When industrial waste is not treated properly (or worse, not treated
at all), it can very easily pollute the freshwater systems that it comes into contact with.
Marine Dumping: The process of marine dumping is exactly what it sounds like, dumping garbage into
the waters of the ocean. The corals of St. Martin Island are almost dead, littered with marine debris, plastic
packages, and food wrap discarded by hundreds of tourists daily. Every year about 2 lakh tons of plastics
enter the Bay of Bengal from Bangladesh (The Daily Star, 2021).
What are the major types of rivers in BD? What is meant by Transboundary River? Discuss the
transboundary riverine issues of BD? (2016)
The major types of rivers in BD: Bangladesh is renowned for its beautiful geomorphic features,
including the massive rivers flowing throughout the country. Within the borders of Bangladesh lie
the bottom reaches of the Himalayan Ranges' water sources, which serve as the primary sources
for rivers that flow through such countries as China, Bhutan, and India and eventually passing into
the Bay of Bengal in Bangladesh. The Bangladesh Rivers also drive various economic activities
such as agriculture, waterway communication, and energy source among others. Since these rivers
play a significant role in the economic growth, it is therefore deemed important to study some of

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the major rivers in Bangladesh, focusing on the countries they flow through. The following are
some of the major rivers in Bangladesh.
Brahmaputra River: The Brahmaputra River is one of the greatest in Asia and the longest to pass through
Bangladesh, covering a length of 1,802 miles, and also cutting across India, Bhutan, and China. It starts
from Kailash in northern Tibet and ends in the Bay of Bengal. The Assam people see this river as both a
blessing and a curse citing the floods it causes on the adjacent land during the monsoon but leaves an
immensely fertile ground after the floods. Peasants take advantage of this land not only to plant food for
their use but also for export purposes. Despite its significance to the Assamese, the river is also prone to
surface water pollution that arises from oil spillages from vehicles and nearby factories.
Jamuna River: The upper Padma flows southeastward to receive the mighty Jamuna River (the name of the
Brahmaputra in Bangladesh) near Rajbari. The Jamuna River is one of the three main rivers of Bangladesh.
It is the lower stream of the Brahmaputra River, which originates in Tibet as Yarlung Tsangpo, before
flowing into India and then southwest into Bangladesh. In the past the course of the lower Brahmaputra
was different and passed through the Jamalpur and Mymensingh districts. In a major magnitude earthquake
on April 2, 1762, the main channel of the Brahmaputra at Bahadurabad point was switched southwards and
opened as Jamuna due to the result of tectonic uplift of the Madhupur tract. The Jamuna is a very wide
river. During the rains it is about 5–8 miles (8.0–12.9 km) from bank to bank. Even during the dry season
when the waters subside, the breadth is hardly less than 2–3 miles (3.2–4.8 km).
Ganges River: The River Ganges originates from the Himalaya Mountains and it is accompanied by three
distinct courses of flow, namely its upper, middle, and lower courses. Famous for its large water basin, it
stretches over a distance of 1,569 miles cutting through India and Bangladesh. Over the years, the
surrounding area has always been liable to floods causing numerous effects to the inhabitants living nearby.
Despite all these effects that are detrimental to the residents, the floods also bring some benefits of land
fertility.
Meghna River: The River Meghna hails from the convergence of the Surma and Kushiyara Rivers.
Considered as one of the most important rivers in Bangladesh, it measures 164 miles and fans out of the
Bay of Bengal. Its delta constitutes four principal mouths, namely Shahbazpur, Bamni, Hatia, and Tetulia.
Transboundary River: A transboundary river is a river that crosses at least one political border, either a
border within a state or an international boundary. Bangladesh has the highest number of these rivers,
including two of the world's largest rivers, the Ganges and the Brahmaputra. Bangladesh has at least 57
major rivers that enter the country from India or Myanmar. The hydrologic and political effects of rivers
that cross significant boundaries are enormous. Rivers have positive effects in that they carry a significant
amount of sediment, which aids in building land in estuarine regions However this sediment raises the
height of riverbeds, thereby causing flooding. International conventions governing water sharing have led
to complex political disputes.
Transboundary riverine issues of BD: India and Bangladesh share 54 common rivers of which agreement
has been reached only on sharing of waters of the river Ganga. The India-Bangladesh Treaty on the Sharing
of Ganga Waters was signed on December 12th 1996 and is based on a sharing formula of the flows
measured at Farakka, during the lean season each year, from 1st January to 31st May. The 30-year Treaty
is renewable by mutual consent. The two countries have a bilateral Joint Rivers Commission (JRC) that
was established in June 1972 to maintain liaison between the two countries to maximize benefits from
common river systems, formulation of flood control works, formulation of proposals on advance flood
warnings, flood forecasting and cyclone warning. The last meeting of JRC took place in Dhaka in

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September 2005. In September 2006, the Water Resources Ministers of both the countries jointly visited
some river sites in both countries and discussed issues relating to riverbank protection, minor lift irrigation
and drinking water schemes. Transboundary water disputes occur whenever demand for water is shared by
any sets of interests, be they political, economic, environmental, or legal. Conflicts over shared water
resources occur at multiple scales, from sets of individual irrigators, to urban versus rural uses, to nations
that straddle international waterways. The issue of managing international rivers would be more convenient
had there been an international government or an overarching authority that could oversee such task.
However, the international system remain anarchical without a clear set of laws for states to follow. The
principles of international law applicable to the use of transboundary resources like rivers are many
and often contradictory. Conflicts over the use of water resources are growing where population
pressures and competing demand for resources are rising. However, research has been going on by
several workers over the world in order to identify the nature of disputes and to find out their possible
resolution.
Sharing And Protecting Bangladesh's Mighty Waterways: Bangladesh and India share as many as 54
distinct rivers, and the Joint River Commission has been established to manage the tensions between the
two countries and their shared waters which started as far back as 1972, shortly after the establishment of
Bangladesh as its own sovereign nation. Recently, there has been a dispute over Teesta River. In 1996 there
was bilateral signed between the two countries and established a 30-year water sharing on the Ganges.
Initially, there was an ad-hoc water sharing agreement made in 1983 between the two countries, wherein
India was allocated 39% and Bangladesh was allocated 36% of the water flow. The new arrangement was
built on the earlier agreement proposing an equal share between the countries

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