The Surma River is a major river in Bangladesh

Bangladesh

Bangladesh , officially the People's Republic of Bangladesh is a sovereign state located in South Asia. It is bordered by India on all sides except for a small border with Burma to the far southeast and by the Bay of Bengal to the south...

, part of the Surma-Meghna River System

Surma-Meghna River System

The Surma-Meghna River System is a river complex in South Asia, one of the three that form the Ganges Delta, the largest on earth. It rises in the Manipur Hills of northeast India as the Barak River and flows west becoming the Surma River and then flows south as the Meghna River, a total of...

. It starts when the Barak River

Barak River

The Barak River is one of the major rivers of southern Assam and is a part of the Surma-Meghna River System. It is the biggest and the most important of all the rivers in the Manipur hill territory, from where it originates....

 from northeast India divides at the Bangladesh border into the Surma and the Kushiyara

Kushiyara River

The Kushiyara River is one of the many rivers in Bangladesh that crosses international boundaries. It is a branch of the Barak River, which originates in the state of Manipur in India and runs along the border of the Indian states of Manipur & Mizoram before getting split into Surma and Kushiyara...

 rivers. It ends in Kishoreganj District

Kishoreganj District

-Place of Interest:Kishorganj is a place of the creed of respectively Sanatana and Loukik Islam. Both Meghna and Brahmaputra river have contributed to its existence. Many traditional rituals are observed every year in Kishoreganj. Among them Kurikhai Mela is one of the most celebrated fair. It is a...

, above Bhairab Bazar, where the two rivers rejoin to form the Meghna River

Meghna River

The Meghna River is an important river in Bangladesh, one of the three that forms the Ganges Delta, the largest on earth fanning out to the Bay of Bengal. Being a part of the Surma-Meghna River System, Meghna is formed inside Bangladesh by the joining of different rivers originaing from the hilly...

. The waters from the river ultimately flow into the Bay of Bengal

Bay of Bengal

The Bay of Bengal , the largest bay in the world, forms the northeastern part of the Indian Ocean. It resembles a triangle in shape, and is bordered mostly by the Eastern Coast of India, southern coast of Bangladesh and Sri Lanka to the west and Burma and the Andaman and Nicobar Islands to the...

.

The average depth of river is 282 feet (86 m) and maximum depth is 550 feet (167.6 m).

Course

From its source in the Manipur Hills near Mao Songsang, the river is known as the Barak River.
At the border with Bangladesh, the river divides with the northern branch being called the Surma River and the southern the Kushiyara River

Kushiyara River

The Kushiyara River is one of the many rivers in Bangladesh that crosses international boundaries. It is a branch of the Barak River, which originates in the state of Manipur in India and runs along the border of the Indian states of Manipur & Mizoram before getting split into Surma and Kushiyara...

. This is where the river enters the Sylhet Depression (or trough) which forms the Surma Basin.

The Surma is fed by tributaries from the Meghalaya Hills to the north, and is also known as the Baulai River after it is joined by the south-flowing Someswari River.

The Kushiyara receives tributaries from the Sylhet Hills and Tripura Hills to the south, the principal one from the Tripura Hills being the Manu. The Kushiyara is also known as the Kalni River after it is joined by a major offshoot (distributary) from the Surma. When the Surma and the Kushiyara finally rejoin in Kishoreganj District

Kishoreganj District

-Place of Interest:Kishorganj is a place of the creed of respectively Sanatana and Loukik Islam. Both Meghna and Brahmaputra river have contributed to its existence. Many traditional rituals are observed every year in Kishoreganj. Among them Kurikhai Mela is one of the most celebrated fair. It is a...

 above Bhairab Bazar, the river is known as the Meghna River.

The Surma passes through many haor

Haor

A haor is a wetland ecosystem in the north eastern part of Bangladesh which physically is a bowl or saucer shaped shallow depression, also known as a backswamp...

s.