North Bihar

Cities and towns shown on the map

The accompanying map provides a geographical overview of North Bihar and shows district boundaries together with major cities, district headquarters and other important towns. The urban centres shown include:

• West Champaran: Bettiah, Bagaha, Narkatiaganj
• East Champaran: Mehsi, Motihari, Raxaul
• Sheohar: Sheohar
• Sitamarhi: Sitamarhi
• Muzaffarpur: Muzaffarpur, Motipur
• Darbhanga: Darbhanga
• Madhubani: Madhubani
• Samastipur: Samastipur
• Supaul: Supaul
• Araria: Araria, Forbesganj
• Kishanganj: Kishanganj
• Purnia: Purnia
• Katihar: Katihar
• Saharsa: Saharsa
• Madhepura: Madhepura
• Khagaria: Khagaria
• Begusarai: Begusarai
• Vaishali: Hajipur

The Government of Bihar's administrative information lists these districts and identifies their respective district headquarters and other administrative centres."Districts, Government of Bihar". Government of Bihar. Retrieved 2 October 2026.

Geography

North Bihar lies in the northern part of the Indian state of Bihar. It is bounded by the Ganga River to the south and the India–Nepal border to the north. The region forms a part of the Middle Gangetic Plain and is one of the most fertile areas of eastern India due to continuous deposition of alluvium by Himalayan rivers.

Physiography

The terrain of North Bihar is almost entirely flat and low-lying, with a gentle slope from north to south. The average elevation ranges between 40 and 100 metres above sea level. The land is composed mainly of recent alluvial deposits, making it suitable for intensive agriculture.

Rivers

North Bihar is drained by several perennial rivers originating in the Himalayas. Major rivers include the Kosi, Gandak, Bagmati, Burhi Gandak, Kamla, Mahananda and the Adhwara river system. Most of these rivers flow southwards and ultimately join the Ganga.

The Kosi River is known for frequent changes in its course and is often referred to as the Sorrow of Bihar due to recurrent floods and heavy sediment deposition.

Floodplains

Large parts of North Bihar fall within active floodplains. Seasonal flooding during the monsoon is common, especially in districts such as Saharsa, Supaul, Madhepura, Darbhanga, Sitamarhi and Muzaffarpur. While floods enrich the soil, they also cause regular damage to crops, settlements and infrastructure.

Soil

The soil of North Bihar is predominantly alluvial. Sandy loam soils are found near riverbanks, while clayey soils occur in low-lying areas. These fertile soils support crops such as rice, wheat, maize, pulses and sugarcane.

Climate

North Bihar experiences a humid subtropical climate with hot summers, a monsoon season from June to September, and cool winters. The average annual rainfall ranges between 1,100 and 1,400 mm, most of which is received during the southwest monsoon.

Seismicity

The region falls under Seismic Zones IV and V, indicating high seismic risk due to its proximity to the Himalayan tectonic region.

Divisions and Districts of North Bihar

Languages

• Bajjika, is predominantly Spoken in Muzaffarpur district, Vaishali, Sitamarhi, Samastipur & its Nearby Districts
• Bhojpuri is predominantly spoken in West Champaran, East Champaran districts and Saran division.
• Maithili is spoken in Darbhanga division, Kosi division and in some parts of Purnia division.
• Surjapuri is spoken in Kishanganj and in some eastern parts of Purnia district and Katihar.

Economy and industries

North Bihar has an economy traditionally based on agriculture, agro-processing, trade and services, alongside a growing network of urban and industrial centres. The region's cities and towns serve different roles as administrative headquarters, commercial markets, transport nodes and centres of manufacturing and services. The Government of Bihar identifies urban development and balanced regional growth as important objectives for the state."Department of Industries, Government of Bihar". Government of Bihar. Retrieved 3 October 2026.

Major economic and industrial centres

Muzaffarpur, Darbhanga, Begusarai, Purnia, Katihar, Bettiah, Motihari, Samastipur, Hajipur, Madhubani, Saharsa and Sitamarhi are among the principal urban centres of North Bihar. They perform different administrative, commercial, agricultural, industrial, educational and transport functions.

Muzaffarpur is one of the major urban and commercial centres of North Bihar. The city is particularly associated with agricultural trade, food processing, manufacturing and regional commerce. The Government of Bihar's statistical profile lists Muzaffarpur among the state's largest cities by population, based on the 2011 Census."Important City of Bihar". Government of Bihar. Retrieved 3 October 2026.

Begusarai is an important industrial centre in the eastern part of North Bihar, while Hajipur has developed as an important commercial, manufacturing and transport centre close to the Patna metropolitan area. Darbhanga, Purnia, Katihar, Motihari, Bettiah and Samastipur function as important regional centres for administration, trade, transport, education and services.

Manufacturing, trade and specialised industries

North Bihar also contains specialised industrial and commercial clusters associated with particular towns and local resources.

• Muzaffarpur: food processing, agricultural trade and manufacturing activities.
• Hajipur: manufacturing, logistics, food processing and industrial activities.
• Begusarai: major industrial activities and large-scale industrial infrastructure.
• East Champaran: trade, agro-based activities and manufacturing associated with towns including Motihari, Mehsi and Raxaul.
• Mehsi, is a notable specialised manufacturing centre of North Bihar. The town has a long-established association with the manufacture of shell and pearl buttons and related handicraft
• Purnia and Katihar: important commercial and agricultural-trade centres serving north-eastern Bihar and adjoining regions.

Urban network

North Bihar's urban network includes large cities, district headquarters, municipalities and smaller market towns. Government administrative records list numerous registration and administrative centres across the region, including Muzaffarpur, Motipur, Mehsi, Motihari, Raxaul, Bettiah, Bagaha, Narkatiaganj, Darbhanga, Madhubani, Samastipur, Hajipur,Begusarai, Purnia, Katihar, Araria, Forbesganj, Kishanganj, Saharsa, Madhepura and Supaul."Registration Offices". Government of Bihar. Retrieved 3 October 2026.

The accompanying map presents these places as part of a connected regional urban network, showing the relationship between district headquarters, major cities, industrial centres and smaller towns.

Rivers and floods

There are several rivers flowing through this region from north to south and merge in the Ganges river. These rivers, along with floods, bring fertile soil to the region on a yearly basis. However, sometimes government sponsored floods causes loss of thousands of lives. Major rivers of North Bihar are Mahananda, Gandak, Kosi, Bagmati, Kamala, Balan, Budhi Gandak.

Natural floods

Since the beginning of human civilization, rivers have been an important part of human life. North Bihar has 7 major rivers and several tributaries to them. North Bihar districts are vulnerable to at least five major flood-causing rivers during the monsoon – Mahananda River, Koshi River, Bagmati River, Burhi Gandak River and Gandak – which originate in Nepal. All these rivers receive water from the Himalayas, so these rivers always have an adequate water supply. Every year, these rivers bring valuable floods for the people of North Bihar. Flood waters used to enter the agricultural land, leave their quite fertile silt and recede to the river. This pattern of humane flood was beneficial for North Bihar, making the land perfectly fertile. However, there are no more natural floods as of today.

Man-made floods

Soon after independence, the Congress Government of Bihar made several attempts to domesticate these rivers. High barriers or Bandhs were made on their both banks. This resulted in inhumane and destructive floods. Bandhs caused deposition of silts in the bottom of rivers, because of which, depth of rivers decreased, and so their water holding capacity also decreased. This is the reason these rivers bring more frequent floods now. With flood water, sand comes in force and gets deposited on the land. This way the land of the region in turning barren. Floods, once a boon for North Bihar, has now become a curse.

Kosi flood 2008,

The 2008 Kosi flood was one of the most disastrous floods in the history of North Bihar, an impoverished and densely populated region in India. A breach in the Kosi embankment near the Indo-Nepal border (at Kusha in Nepal) occurred on 18 August 2008. The river changed course and inundated areas which were not flooded in decades. The flood affected over 2.3 million people in North Bihar.

The flood killed 250 people and forced nearly 3 million people from their homes in North Bihar. More than 300,000 houses were destroyed and at least 340,000 hectares (840,000 acres) of crops were damaged. Villagers in North Bihar ate raw rice and flour mixed with polluted water. Hunger and disease were widespread. The Supaul district was the worst-hit; surging waters swamped 1,000 square kilometers (250,000 acres) of farmlands, destroying crops.

2017 North Bihar Floods

The 2017 North Bihar Floods affected 19 districts of North Bihar causing death of 514 people. This flood was result of sudden increase in water discharge through the Gandak, Burhi Gandak, Bagmati, Kamla, Kosi and Mahananda Rivers due to heavy rain in the catchment areas of the major rivers of north Bihar in Nepal. Araria district accounted for 95 deaths alone, followed by Sitamarhi (34), West Champaran (29), Katihar (26), East Champaran (19) while 22 have died in Madhubani, Supaul (13) and Madhepura (15). 11 deaths were reported in Kishanganj, while Darbhanga accounted for 19 deaths, Purnea (9), Gopalganj (9), Sheohar (4), Muzaffarpur (7), Samastipur (1) and Saharsa (4) registered four deaths each while Khagaria and Saran accounted for 7 deaths each. Nowadays, around 1.71 people on average are affected by floods alone.