Dying Gorai still cries for new lease of life

Amanur Aman, Kushtia  The Daily Star, May 7, 2009

Gorai River that once acted as feeder for over a dozen rivers in the south-western region of the country, itself now on the verge of death. Photo: STAR

Once mighty Gorai River, the main branch of the Padma, now sees a lowest ever flow, posing a serious ecological threat to the country’s south-western region.

Due to drastic fall in the flow of Gorai River, at least seven of the 15 rivers dependent on it are now nearly dead while eight others are following.

The nearly dead rivers are Hisna, Kaliganga, Kumar, Hamkumra, Harihar and Chitra.

The 386-kilometre Gorai River, an important source of fresh water in the south-western region, depends on the Padma River for its flow.

As the Padma itself remains lean in the dry season (December-May) for over three decades, Gorai flow during the period also sees gradual decline.

Consequently, intrusion of increased saline water in the costal areas in greater Khulna region poses a serious threat to the world’s largest mangrove forest the Sundarbans.

Increasing salinity in the region also leaves an adverse effect on water quality, nature, fishery, agriculture, navigability and trade in a vast area of the region.

To keep flow of Gorai River normal, successive governments took initiative to dredge the riverbed in 1977, 1983, 1984, 1992 and 1996 but with very little achievements.

In 1996, the then government took a large-scale dredging scheme on the Gorai.

Under the Tk 267.3crore project, 34 km river was dredged in two phases.

But before its maintenance dredging started, the project work was abandoned in 2001 when the government led by BNP took over.

To keep Gorai River alive, around 50,000 to 55,000 cusec of water is necessary in the Padma, the parent river of the Gorai.

The WDB sources said Bangladesh gets on average 38,000 to 42,000 cusec water in last three months of dry season although it was supposed to get 55,000 to 70,000 cusec as per the India-Bangladesh agreement signed in 1996.

Due to withdrawal of Ganges water by India at Farakkar in the upstream, quantity of water in the Padma sees decline every year.

Scanty flow of water in the Padma is also affecting the GK (Ganges-Kobadak) project, which has been used to irrigate around 1.16 lakh hectares of land in the region since 1959.

Meanwhile, responding to the government’s plan to resume excavation of the Gorai River, a group of donors at a meeting yesterday assured the prime minister of extending necessary assistance for it.

Dutch Ambassador in Dhaka Bea Tan Tusscher, German Ambassador Frank Mayke, Japanese Ambassador Masayuki Inoue, World Bank’s acting Country Director Tahaseen Sayed and Food and Agriculture Organization (FAO) representative Ad Spijkers were present from the donors’ side.

The dying rivers have spoken

NewAge, May 1, 2009

For Bangladesh, a country that would probably fare the worst in the face of climate change because of raised sea levels, such consequences of glacial retreats in the faraway Himalayas could be disastrous. As large swathes of Bangladesh’s coastal belt are already ravaged by cyclones, salinisation and rising sea-levels, scientists say the decrease in volume of year-round freshwater from Himalayan glaciers could bring disease, drought, and deluge of unseen proportions, writes Mahtab Haider*

THE implications of the study released by the National Centre for Atmospheric Research in the United States this month are ominous for Bangladesh. The study reveals that global warming is drying up some of the biggest river systems across the world faster than was previously thought, and more so for those rivers in highly populated areas, which are drying up at more alarming rates. ‘In the subtropics this [decrease] is devastating, but the continent affected most is Africa,’ said Kevin Trenberth of the atmospheric research centre. ‘The prospects generally are for rainfalls, when they do occur, to be heavier and with greater risk of flooding and with longer dry spells in between, so water management becomes much more difficult.’
   

According to the UK’s Guardian newspaper, the scientists examined recorded data and computer models of flow in 925 rivers, constituting about 73 per cent of the world’s supply of running water, from 1948 to 2004. ‘It found that climate change had had an impact on about a third of the major rivers. More than twice as many rivers experienced diminished flow as a result of climate change than those that saw a rise in water levels.’
   

According to the NCAR scientists, the Ganges system is among those showing some of the most significant downward trends in freshwater flow as a result of dams and increased population pressures upstream, but also because higher temperatures are causing higher rates of evaporation, with changing rainfall patterns failing to feed into the river system.
   

For Bangladesh, India, and the region as a whole, there is no doubt that reduced freshwater flows in the Ganges river system will prove devastating in the long run. The effects will be multifarious, effecting agriculture, nutrition, navigability of the rivers, and most of all allowing swathes of land along the coast to become unfit for habitation as rising seawaters advance further inwards.
   

Diminishing freshwater flows on the Ganges will likely debilitate predominantly agrarian economies along its banks and may eventually strip the region’s people of the major source of protein in their diets, as a result of a reduction in the quantity of micro-nutrients that debouch into the Bay of Bengal, originating in the Himalayas. Sundarban, on both sides of the border, are after all the richest fish nursery in all of South Asia, largely as a result of the ecology of the Ganges from its headwaters to its watershed.
   

What’s worse, diminishing freshwater flows across South Asian river systems including the Ganges and the Brahmaputra will be further reinforced, say scientists, as a result of shrinking glaciers. The Himalayas have the largest concentration of glaciers outside the polar caps. During the dry season, when water is in short supply, these glaciers feed eight of Asia’s greatest rivers: to the east, south and west – the Yangtze, Hwang Ho, Salween, Irrawady, Mekong,

Tsangpo/Brahmaputra/Jamuna, Indus, and the many tributaries of the Ganges including the Kosi, Gandaki and Karnali that debouch from the Nepali midhills. The glaciers of the Himalayas as a whole are referred to by scientists as the ‘water towers of Asia’, because they serve as storage that release water throughout the year into the rivers of Asia.
   

According to a report by the World Wildlife Fund, 67 per cent of the Himalayan glaciers are melting at a startling rate and ‘the major causal factor has been identified as climate change’. The Khumbu Glacier, from where Tenzing Norgay and Edmund Hillary began their historic ascent of Mt Everest, has retreated more than five kilometres since they climbed the mountain in 1953. The 30km Gangotri Glacier in India, near the Badrinath pilgrimage centre, has been receding over the last three decades at more than three times the rate than it had during the previous two centuries. The Rika Samba Glacier in Nepal’s Dhaulagiri region is retreating at 10m per year. Such measurements alarm scientists, who were previously used to gauging glacial retreat in centimetres.
   

And this is not just happening in Nepal’s mountains. Across the Himalayas, from Tibet in the north to the Karakoram in the west, the glaciers are melting so fast that the WWF fears that a quarter of the ice floes could disappear by 2050. In the climate equilibrium that has evolved over millennia, the glaciers (because of their white colour) reflect back sunlight, keeping the high-altitude peaks within a certain temperature range. As the glaciers start melting and receding as a result of global warming, however, they reveal the darker rock underneath, which in turn absorbs more sunlight and intensifies the melting process. Meanwhile, greenhouse gases trapped in the atmosphere then reflect that heat back onto the earth’s surface, accelerating the process even further.
   

‘The melting glaciers represent a time-bomb that is ticking away even as we speak,’ cautions Pradeep Mool, a specialist on glaciers at Kathmandu’s International Centre for Integrated Mountain Development. ‘Glaciers melt to form high-altitude lakes, dammed with debris and moraine that characterises the landscape of the Himalayas. But as the water from glacial melt accumulates over the years, these dams which are structurally weak suddenly give way, resulting in what we call glacial lake outburst floods, or GLOFs.’
   

GLOFS, indeed, are the most obvious results of glacial melt. In 1964, one such GLOF destroyed entire stretches of a highway in China and washed 12 timber trucks more than 70km downstream. A GLOF at Nepal’s Dig Tsho glacier in 1985 destroyed a hydroelectric project near Namche Bazaar, as well as bridges, houses and farmlands worth. The total estimated damage was $4 million. ‘And it isn’t just water that crashes down into the valleys,’ says Mool, holding up a photograph from a 1991 outburst in Nepal that swept away entire villages. ‘You have rocks and other debris that rush downriver at enormous speed.’
   

Since 1964, Nepal alone has witnessed 13 catastrophic GLOF events. There are over 5000 glacial lakes between Bhutan, Pakistan, India, Nepal and Tibet/China, and scientists regard at least 90 of these lakes to be potentially dangerous. ‘The real problem,’ sighs Mool, ‘is that we don’t even know the extent of the problem, since countries such as India and Pakistan will not share the data and maps of their mountainous regions.’ As the glaciers melt and recede, more glacial lakes are expected and hence more incidence of GLOFS.
   

‘Contrary to popular perception, this isn’t Nepal’s problem or Pakistan’s problem, but a problem for the entire Subcontinent,’ urges Madan Lal Sreshtha. ‘The melt waters from these retreating glaciers mother the river systems of the Brahmaputra and the Ganga, so if these glaciers eventually disappear, the flow in the rivers will be drastically reduced and almost negligible during the non-monsoon months. Says Shrestha, ‘Glaciers accumulate snow during the South Asian monsoon and it is meltwater from these glaciers that feeds river systems that flow through India and Bangladesh during the dry season until April-May,’ he explains. ‘As the glaciers recede, not only will these rivers flood during the rainy season – with the water that is not frozen and held back by the glaciers – but in the lean seasons, there will also be less and less water in these rivers. Eventually, when the glaciers disappear, there will only be a trickle of water in these great rivers in the winter.’
   

The decrease in non-monsoon flows would affect the populated plains of South Asia in a thousand different ways. Winter agriculture would suffer, recharge of underground aquifers would be affected thus reducing groundwater reserves, and the use of water for urban and industrial purpose would also be affected, as would water transport, fisheries, wetlands, and water-dependent wildlife. Overall, we are looking at long-lasting impact that that has not even begun to be studied at a time when we are just awakening to the fact of receding glaciers.
   

For Bangladesh, a country that would probably fare the worst in the face of climate change because of raised sea levels, such consequences of glacial retreats in the faraway Himalayas could be disastrous. As large swathes of Bangladesh’s coastal belt are already ravaged by cyclones, salinisation and rising sea-levels, scientists say the decrease in volume of year-round freshwater from Himalayan glaciers could bring disease, drought, and deluge of unseen proportions.
   

A model developed in part by the Indian Centre for Ecology and Hydrology reveals that glacial melt will result in ‘an increase in river discharge at the beginning causing widespread flooding in the adjacent areas.’ But after a few decades, the model warns, this situation will reverse and water levels in these rivers will start declining to permanently decreased levels. In the upper Indus, the study shows initial increases of between 14 and 90 percent in flows over the first few decades, followed by flows decreasing between 30 and 90 percent over the following century.


When world leaders meet in December this year to hammer out a long term deal on how to tackle the spectre of climate change, they should be reminded that the fallout of global warming is no longer in the realm of academic projections. People in some of the poorest parts of the world have already started living these realities.
   

*mahtabhaider@gmail.com

River Nabaganga in its death throes

Continued encroachment on bank blamed

Delwar Kabir . Jhenidah, NewAge, April 23, 2009

The River Nabaganga in Jhenidah is in its death throes because of the continued encroachment on the bank of the river by a section of influential persons.
   

Land grabbers, after making houses along the bank of the river, are indiscriminately cutting earth of the bank for sale, local sources said. 
   

Although cutting of the river bank at different points continues unabated, the district administration remains silent over the matter, they alleged. 
   

The only river in the district has dried up at Mathurapur and Parmathurapur points under district sadar upazila because of the continued encroachment on the river bank. 

As a result, the people living in the nearby villages suffer a lot as their houses and crop lands go under river water every monsoon, local people said.
   

During a visit, our correspondent found that many houses and several markets have been built along the river bank at different places. 
   

Some people were seen cutting the earth of the river bank. 
   

At present, cutting of the river bank continues in different points covering Gilabaria, Mathurapur villages under sadar upazila and Chandpur, Hakimpur, Daulatpur and Gobordanga under Harinakunda upazila of the district.
   

The land grabbers are influential persons in the locality and so, no body dares to speak against them,’ Aktar Hossain, a resident of village Mathurapur, said. 
   

‘If cutting of the river bank continues, the river will lose its existence in near future,’ he added.
   

The convener of the district environment and animal protection committee Masud Ahmed Sanju told New Age that they had submitted a memorandum to the deputy commissioner two times urging steps against illegal earth cutting.. 
   

But the authorities concerned are yet to pay any heed to their plea, Masud said. 
   

‘The committee will go for strong movement if the authorities do not take immediate steps to save the river from the land grabbers,’ he added.
   

Earlier, officials at the district administration said they would soon take steps against the encroachers.

Water Levels Dropping in Some Major Rivers as Global Climate Changes

National Center for Atmospheric Research (NCAR), April 21, 2009

BOULDER—Rivers in some of the world’s most populous regions are losing water, according to a new comprehensive study of global stream flow. The study, led by scientists at the National Center for Atmospheric Research (NCAR), suggests that in many cases the reduced flows are associated with climate change. The process could potentially threaten future supplies of food and water.

The results will be published May 15 in the American Meteorological Society’s Journal of Climate. The research was supported by the National Science Foundation, NCAR’s sponsor.

The scientists, who examined stream flow from 1948 to 2004, found significant changes in about one-third of the world’s largest rivers. Of those, rivers with decreased flow outnumbered those with increased flow by a ratio of about 2.5 to 1.

This map shows the change in runoff inferred from streamflow records worldwide between 1948 and 2004, with bluish colors indicating more streamflow and reddish colors less. In many heavily populated regions in the tropics and midlatitudes, rivers are discharging reduced amounts into the oceans. In parts of the United States and Europe, however, there is an upward trend in runoff. The white land areas indicate inland-draining basins or regions for which there are insufficient data to determine the runoff trends. (Graphic courtesy Journal of Climate, modified by UCAR.)

Several of the rivers channeling less water serve large populations, including the Yellow River in northern China, the Ganges in India, the Niger in West Africa, and the Colorado in the southwestern United States. In contrast, the scientists reported greater stream flow over sparsely populated areas near the Arctic Ocean, where snow and ice are rapidly melting.

“Reduced runoff is increasing the pressure on freshwater resources in much of the world, especially with more demand for water as population increases,” says NCAR scientist Aiguo Dai, the lead author. “Freshwater being a vital resource, the downward trends are a great concern.”

Many factors can affect river discharge, including dams and the diversion of water for agriculture and industry. The researchers found, however, that the reduced flows in many cases appear to be related to global climate change, which is altering precipitation patterns and increasing the rate of evaporation. The results are consistent with previous research by Dai and others showing widespread drying and increased drought over many land areas.

The study raises wider ecological and climate concerns. Discharge from the world’s great rivers results in deposits of dissolved nutrients and minerals into the oceans. The freshwater flow also affects global ocean circulation patterns, which are driven by changes in salinity and temperature and which play a vital role in regulating the world’s climate. Although the recent changes in the freshwater discharge are relatively small and may only have impacts around major river mouths, Dai said the freshwater balance in the global oceans needs to be monitored for any long-term changes.

Conflicting studies

Scientists have been uncertain about the impacts of global warming on the world’s major rivers. Studies with computer models show that many of the rivers outside the Arctic could lose water because of decreased precipitation in the mid- and lower latitudes and an increase in evaporation caused by higher temperatures. Earlier, less comprehensive analyses of major rivers had indicated, however, that global stream flow was increasing.

Dai and his co-authors analyzed the flows of 925 of the planet’s largest rivers, combining actual measurements with computer-based stream flow models to fill in data gaps. The rivers in the study drain water from every major landmass except Antarctica and Greenland and account for 73 percent of the world’s total stream flow.

Overall, the study found that, from 1948 to 2004, annual freshwater discharge into the Pacific Ocean fell by about 6 percent, or 526 cubic kilometers–approximately the same volume of water that flows out of the Mississippi River each year. The annual flow into the Indian Ocean dropped by about 3 percent, or 140 cubic kilometers. In contrast, annual river discharge into the Arctic Ocean rose about 10 percent, or 460 cubic kilometers.

In the United States, the Columbia River’s flow declined by about 14 percent during the 1948-2004 study period, largely because of reduced precipitation and higher water usage in the West. The Mississippi River, however, has increased by 22 percent over the same period because of greater precipitation across the Midwest since 1948.

The impacts of melting

Some rivers, such as the Brahmaputra in South Asia and the Yangtze in China, have shown stable or increasing flows. But they could lose volume in future decades with the gradual disappearance of the Himalayan glaciers feeding them, the authors warned.

“As climate change inevitably continues in coming decades, we are likely to see greater impacts on many rivers and water resources that society has come to rely on,” says NCAR scientist Kevin Trenberth, a co-author of the study.

Modhumati, Nabaganga river continue to dry up

Livelihood of fishermen threatened

NewAge, June 17, 2008. 

The Modhumati and Nabaganga — two major rivers in Narail — has dried up at different points, affecting the livelihood of a large number of people in the district.
   

Hundreds of people, particularly the fishermen, have become jobless due to continued drying up of the two rivers, according to local sources.
   Fishermen in the district are passing through hard times as they hardly find any fish due to siltation and drastic fall in the water level of the two rivers, the locals said.
   

Even movement of people in small boats is also being hampered due to continued siltation and emergence of a good many shoals in the rivers, they added.
 ‘Now I find it very difficult to earn my livelihood. I have no alternative to earning as continued siltation has made the river almost dead,’ a fisherman living near the River Modhumoti, said.
   

The two rivers lost their navigability long ago forcing the service of water vessels including steamer and launches to stop.
 The rivers once played a vital role in transportation of merchandise and movement of people to different places.
 A good many market places had been developed near the banks of the rivers passing through three upazilas of the district— sadar, Lohagora and Kalia upazilas.
 These market places always remained abuzz with trade activities.
   

Farmers living in the river-side areas, who used to irrigate their crop fields with the water from these rivers, cannot use river water now due to siltation and fall in the water level.
   The sharp fall in the water level of the two rivers and their tributaries has resulted in almost disappearance of fish, local sources said.
 Once various kinds of fish were found aplenty in the two rivers and fishermen got huge catch.
   

The ferry services on the Baroipara-Kalia, Kalna-vatiapara, Phordanga-Gopalgonj and Bardia-Mahajan routes are also frequently disrupted due to shoals at several points of the rivers.
The total area of shoals in the two rivers covers around 3,000 hectares, according to sources at the Department of Agriculture Extension, Narail.


Local people have long been demanding that the government should immediately dredge the rivers to increase their navigability of the two rivers.