Rivers of Bangladesh: Padma, Jamuna and Meghna — the Rivers That Built a Delta

Stand on the bank of the Padma near Goalundo in late July and you are watching a measurable share of a continent's water go past. The river in front of you is carrying the combined flow of the Ganges and the Brahmaputra at monsoon strength, and a few hours downstream it will be joined by the Meghna and poured into the Bay of Bengal in a single vast outflow. Almost everything that defines Bangladesh — its soil, its food, its transport, its floods, its very outline on the map — is a product of that water. The country is not simply crossed by rivers. It was built by them, grain by grain, out of silt carried down from the Himalaya and the Tibetan Plateau, and it is still being rebuilt by them every year: banks collapse in one district, new islands rise in another, and the map quietly changes.

The Delta and Its Three Great Rivers

Bangladesh occupies most of the Bengal Delta, the largest river delta on Earth, formed where three great river systems meet the sea. The Ganges, the Brahmaputra and the Meghna between them drain a catchment of roughly 1.5 million square kilometres spread across five countries — China, Nepal, Bhutan, India and Bangladesh — yet almost all of that water leaves the mountains and funnels through this one small, low-lying country on its way to the ocean. The combined average discharge of the three systems is on the order of 40,000 cubic metres per second, a flow ranked second or third among the world's river systems in most published comparisons, behind the Amazon alone. Well over a trillion cubic metres of water passes through Bangladesh in a year; the Bangladesh Water Development Board puts the total annual discharge at about 1,400 billion cubic metres.

The sediment figures are even more striking. The rivers carry on the order of a billion tonnes of silt a year in recent estimates — older classic studies put the figure closer to two billion tonnes — which by most accounts is the largest sediment load of any river system on Earth. It is this silt that made the country: the delta plain is Himalayan rock ground down and spread out to sea. The delivery is violently seasonal. Roughly four-fifths of the year's water arrives in the monsoon months between June and October, so the system's normal condition is not a steady flow but an annual flood pulse — too much water in summer, too little in winter. Life in Bangladesh, from the boro and aman rice calendars to the design of its houses and embankments, is organised around that pulse.

Padma: The Ganges in Bangladesh

The Ganges enters Bangladesh from India in the north-west, and for the roughly 260 kilometres from the border to its confluence with the Jamuna near Goalundo it keeps the name Ganges. Just before it crosses the border — about 18 kilometres upstream, in West Bengal — stands the Farakka Barrage, which has shaped the river's modern history. Commissioned in April 1975, the barrage can divert up to 40,000 cusecs of dry-season flow through a feeder canal into the Bhagirathi–Hooghly river to flush silt from Kolkata Port. Bangladesh, which receives what remains, has argued ever since that the diversion starves its south-west in the dry season; India has maintained that the diversion is a small share of the river's flow and essential to its port. The dispute was partly settled by the Ganges Water Sharing Treaty of December 1996, which fixed how dry-season flows at Farakka would be divided between January and May.

That settlement is now expiring. The treaty's 30-year term ends on 12 December 2026, it has no automatic renewal clause, and as of November 2026 no successor agreement had been announced. Bangladesh is seeking a new or revised treaty with an explicit guarantee of its share — a protection the 1996 text dropped — and its water resources minister said in October 2026 that Dhaka expected an agreement before the lapse, while noting that its requests to open negotiations had gone unanswered since June. India has responded that river matters belong in the Joint Rivers Commission; technical talks have continued there through 2026, including joint flow measurements at Farakka, and an Indian parliamentary committee has urged New Delhi to begin renewal talks without delay. Both governments say they want an agreement; the dry season that begins in January 2027 will arrive whether they reach one or not.

Below Goalundo, the Ganges meets the Jamuna and the combined river takes the name Padma. Even by world standards it is enormous: its mean flow is about 30,000 cubic metres per second, which would make the Padma alone one of the largest rivers on Earth by discharge, and it runs for a little over 100 kilometres before meeting the Meghna at Chandpur. Its great distributaries peel off southward — the Arial Khan towards Barisal, and the Gorai, which takes off near Kushtia and has historically carried the Ganges' fresh water into the south-west and down to the Sundarbans. The Gorai shows what is at stake in the dry-season argument: researchers have recorded no natural dry-season flow in it since 1988, and its decline is widely linked to the shrinkage of the Ganges' dry-season flow and to the advance of salinity through the south-western districts. It is across the Padma at Mawa–Jajira that Bangladesh built its longest bridge, the Padma Bridge, opened in 2022 where ferries once queued for hours.

Jamuna: The River That Changed Course

The Jamuna is the Brahmaputra in Bangladeshi dress — and it is a reminder that even giant rivers can move. The Brahmaputra begins in Tibet as the Yarlung Tsangpo, swings around the eastern Himalaya, crosses Assam, and enters Bangladesh through Kurigram. But until a little over two centuries ago, its main flow did not take this course at all. Rennell's maps of the 1760s show the river running east of the Madhupur Tract, down the channel now called the Old Brahmaputra, past Mymensingh and towards the Meghna. Then, in the standard account preserved in Banglapedia, a major earthquake in 1782 and the catastrophic flood of 1787 broke the river out of its old bed and sent it down a new course to the west — the river we now call the Jamuna. The shift unfolded over some thirty years, and the same 1787 flood tore the Teesta out of its old channels and threw it into the Brahmaputra as well. The Old Brahmaputra dwindled into the modest river it remains today.

The modern Jamuna runs about 205 kilometres from Bahadurabad to the Goalundo confluence, and it runs wide: not a single channel but a braided belt of interlacing streams separated by chars — temporary sand islands that appear, grow, are farmed and are eaten away again. An estimated five to six million people live on more than a thousand chars across the great rivers, farming land that may not exist in ten years' time. The Jamuna's flood of August 1988, the highest recorded, peaked at 98,600 cubic metres per second. It is no coincidence that Bangladesh's first great river crossing was built here: the 4.8 kilometre Jamuna Bridge, opened in 1998 between Tangail and Sirajganj, joined the country's east and west by road and rail for the first time.

Meghna: The Haor-Fed Giant

The third system is the quietest of the three and in some ways the most purely Bangladeshi. Its headstream, the Barak, rises in the Manipur hills of north-east India and enters Bangladesh near Amalshid in Sylhet, where it divides into two rivers, the Surma and the Kushiyara. The Surma winds west and south through the haor basin — a saucer of some 373 seasonally flooded wetlands across the north-eastern districts that in the monsoon merges into a single inland sea, and whose pre-monsoon flash floods each year race against the ripening boro rice crop. The basin is fed by streams pouring off the Meghalaya hills, hard against the Cherrapunji area, one of the wettest places on Earth, which gives the Surma–Meghna a flashy, fast-rising character quite unlike the snow-fed giants.

The Surma and Kushiyara reunite, take in the Old Brahmaputra near Bhairab Bazar, and become the Meghna — the Upper Meghna as far as Chandpur, where it receives the Padma, and the Lower Meghna below. At 669 kilometres within Bangladesh, the Surma–Meghna is the country's longest river system, and the Meghna is the widest river lying wholly inside its borders, spreading to some 12 or 13 kilometres across near Bhola as it approaches the sea. It reaches the Bay of Bengal through four principal mouths — the Tetulia, Shahbazpur, Hatia and Bamni channels — around a shifting archipelago of estuarine islands where new land is still rising out of the silt the three systems deliver. The estuary is also one of the country's great fisheries, and its tidal reaches, scoured twice daily, are among the most powerful stretches of river water anywhere in Bangladesh.

A Country of Seven Hundred Rivers

Ask how many rivers Bangladesh has and you will get an argument rather than an answer. Banglapedia's figure of about 700 is the one everyone quotes; the National River Conservation Commission has counted 907; the Water Development Board's own publications have variously listed 310 rivers flowing in the summer season and 405 in a six-volume inventory. The disagreement is not really about arithmetic. In a delta, what counts as a river depends on the season and the definition: channels that are modest streams in March become broad waterways in August, rivers split into two names and rejoin, and the same watercourse may be called one thing in one district and another downstream. The honest summary is that several hundred named rivers, with a total length of about 24,000 kilometres, thread the country — and that 57 of them are international: 54 shared with India and three flowing in from Myanmar, according to the Joint Rivers Commission.

Beyond the great three, whole regions have their own river worlds. In the north, the Teesta comes down from Sikkim and is the lifeline of the Rangpur region, alongside older, quieter rivers like the Atrai and the once-mighty Karatoya. Around Dhaka runs a ring of smaller rivers that made the capital a port city: the Buriganga, an offshoot of the Dhaleshwari, along its southern edge; the Turag to the west; the Balu to the east; and the Shitalakshya, fed from the Old Brahmaputra, flowing past Narayanganj. The south-west is a tidal maze of the Passur, Sibsa and Baleswar threading through the Sundarbans. And in the south-east, outside the GBM system entirely, the Karnaphuli runs 270 kilometres from the Lushai Hills of Mizoram through the Chittagong Hill Tracts to the sea — dammed at Kaptai in 1962 for the country's only hydroelectric station, carrying the Port of Chittagong near its mouth, and crossed since 2023 by the Karnaphuli Tunnel beneath its lower reaches.

These rivers remain working infrastructure. BIWTA counts 5,968 kilometres of waterway navigable by mechanised vessels in the monsoon, shrinking to 3,865 kilometres in the dry season — down from more than 8,000 kilometres within living memory, as channels silted up. Launches, ferries and cargo boats still move millions of passengers and much of the country's bulk freight, and for the southern districts the river is not an alternative to the road but the road itself.

Rivers Under Pressure

The forces that built Bangladesh are also, unmanaged, a standing threat to the people living on them. Riverbank erosion is the delta's quiet disaster. CEGIS calculates that between 1973 and 2007 the Jamuna alone eroded nearly 89,000 hectares of land, the Padma about 28,000 hectares and their tributaries over 38,000 hectares more; older assessments estimated that around a million people a year were directly affected. More recent official counts are narrower — the planning minister told parliament in September 2026, citing Bureau of Statistics reports, that erosion displaces an average of over 15,000 people, some 3,500 families, a year — and research summaries offer figures in between. The estimates differ by method and period, but every one of them describes the same reality: thousands of families a year watching their farmland, homes and villages slide into the current, many of them ending in the slums of the cities.

The dry season brings the opposite problem. Upstream, the argument over the Ganges remains unresolved as the 1996 treaty lapses, and the Teesta agreement — drafted in 2011, blocked then by objections from West Bengal, and still unsigned fifteen years later even after West Bengal's change of government in 2026 raised hopes — leaves some 14 million people in the northern districts dependent on a river whose dry-season flow has fallen sharply. On the ground, less dry-season water means the Gorai runs dry, salinity pushes further into the south-west's farmland and into the Sundarbans, and navigable channels shoal: the network that once offered over 8,000 kilometres of monsoon waterway now offers under 6,000.

Around the capital, the pressure is chemical. The Department of Environment's 2023 water-quality report recorded dissolved oxygen in the Buriganga as low as 0.1 milligrams per litre in the dry season — against the 5 milligrams per litre that fish need to survive — and a River and Delta Research Centre study counted more than 390 industrial, municipal and private outlets discharging into the four rivers around Dhaka. BIWTA has since identified 424 waste outlets into the capital's rivers, a naval assessment in 2026 found the Buriganga's average dissolved oxygen still under 3 milligrams per litre, and the government has ordered an integrated action plan for the ring of rivers — Buriganga, Turag, Balu, Shitalakshya, Dhaleshwari — that made Dhaka a city in the first place. Add a changing climate — a rising sea pushing salt further inland and a monsoon arriving in sharper bursts — and the pattern is consistent: a river system of unmatched abundance being squeezed from every side at once.

Conclusion

Bangladesh is sometimes described as a gift of its rivers, and the geography is literal: the country is the surface that the Padma, the Jamuna and the Meghna have laid down and are still laying down. Its several hundred rivers feed its farms, carry its trade, fill its fisheries and define its seasons — and they also flood, erode, salinise and, around its cities, absorb its waste. The questions that will decide the rivers' future are now plain: whether the two governments that share them can replace the expiring Ganges treaty and settle the Teesta, whether the dry-season flows that hold back the sea can be kept alive, and whether a country built by clean silt can stop poisoning the water that runs through its capital. The rivers built Bangladesh. What Bangladesh does with them next is the open question of its geography.