Historic River Sluice & Transit Lifeline

Koshi Barrage (also known as Koshi Bridge) is a historic hydraulic flood control structure and vital roadway sluice spanning the powerful Koshi River in eastern Nepal. Serving as a key link along the Mahendra (East-West) Highway, the barrage connects Sunsari District on the east with Saptari District on the west. Positioned right near the international border with India, this massive 56-gate engineering landmark controls river currents, supports vital irrigation networks, and provides a scenic stopover famous for river vistas, fresh local fish delicacies, and wetland birdwatching.

Quick Facts and Basic Information

Location: Spans between Bhardaha, Saptari and Bhokraha Narasimha / Koshi Rural Municipality, Sunsari, Nepal

River System: Sapta Koshi River (Average discharge: 2,166 m³/s / 76,500 cu ft/s)

Construction Period: 1958 to 1962 (Operational since 1963)

Key Treaty: Koshi Agreement signed between Nepal and India on April 25, 1954

Engineering Structure: 56 flood control sluice gates built by Joseph and Company Limited

Highway Connection: Carries national vehicular, bicycle, and pedestrian traffic on the East-West Highway

Nearby Reserve: Koshi Tappu Wildlife Reserve (3–4 miles north)

Main Activities: Sightseeing, sunset views over the vast riverbeds, river photography, and sampling local fish cuisine

Conception, History & Treaty Framework

The mighty Koshi River, formed by seven major Himalayan tributaries, historically shifted its course by over 130 kilometers westward across centuries, causing catastrophic seasonal flooding across the plains of Nepal and northern Bihar. Due to the devastation affecting nearly 21,000 square kilometers of fertile agricultural land annually, the river earned the moniker the “Sorrow of Bihar”. To tame the deluge and harness water for trans-boundary irrigation and power, the Governments of Nepal and India signed the historic Koshi Agreement on April 25, 1954.

Under this bilateral treaty, construction commenced in 1958 and concluded in 1962, executed by Indian engineering firm Joseph and Company Limited. The treaty granted a 199-year lease for the barrage operation to India, placing the physical operation, maintenance, and regulation of the sluice gates under the Water Resources Department of the Government of Bihar. The opening and closing of all 56 gates are coordinated during high monsoon inflows based on specific flood warning thresholds and discharge alerts communicated between Nepalese hydrological authorities and Indian river control engineers.

Heavy monsoon events—such as the devastating floodings in 2008 (Kusaha embankment breach) and 2017—have repeatedly tested the infrastructure. As silt accumulation elevates the riverbed higher than surrounding floodplain settlements, debates regarding structural aging and future endurance continue, leading to strict weight checks and alternative river routing solutions.

Alternative Crossing: The Chatara Bridge Corridor

To reduce heavy highway congestion, prevent over-reliance on the aging barrage structure, and ensure continuous transport during extreme floods, the Government of Nepal constructed the Koshi Bridge at Chatara (connecting Chatara in Sunsari with Barahakshetra and Rampur Tokani in Udayapur).

Located upstream near the Himalayan foothills, the modern Chatara permanent motorable bridge provides a vital secondary east-west bypass via the Madan Bhandari Highway (Dharan–Chatara–Gaighat corridor), ensuring unhindered transport across eastern Nepal even when monsoon water levels at the main barrage require emergency protocols.

Nearby Destinations to Visit

Nearby Destination	Distance / How to Reach	What to See & Links
Koshi Tappu Wildlife Reserve	North (~5 to 8 km / 15 min drive)	Explore Koshi Tappu, Nepal’s premier Ramsar wetland site famous for the last surviving wild water buffaloes (Arna), Gangetic river dolphins, and migratory wetland birds.
Barahakshetra Dham & Chatara	North upstream (~35 km / 50 min drive or via jet boat)	One of Nepal’s four sacred Char Dhams dedicated to Lord Varaha, situated at the holy confluence of the Koka and Koshi rivers, accessible by river jet-boat.
Taal Talaiya Wetland Park (Itahari)	East via Itahari (~42 km / 1 hr drive)	A lush recreational wetland park featuring natural lakes, stone sculpture exhibits, children’s amusement zones, and quiet picnic woodlands.
Dharan City & Bhedetar Hills	Northeast (~50 km to Dharan / 1.2 hr drive)	Explore Dharan and climb upward toward Bhedetar Hill Station for cool panoramic Himalayan views.
Chinnmasta Bhagwati Temple (Saptari)	Southwest via Rajbiraj (~40 km / 1 hr drive)	A celebrated historic Shakti Peeth pilgrimage temple attracting hundreds of thousands of devotees from across Nepal and northern India.
Itahari & Biratnagar Commercial Hubs	East along East-West Highway (~35 km to Itahari)	Explore Itahari and transit onward to Biratnagar for flight connections, star hotels, and commercial markets.

Travel Tips – Do’s and Don’ts

Do’s

Park your vehicle in designated parking lots on either end of the bridge before walking onto the pedestrian sidewalks.
Try authentic, freshly caught Koshi river fish curries and delicacies at local roadside eateries near the eastern barrage approach.
Carry binoculars and zoom cameras to spot migratory waterfowl, kingfishers, and sunbathing river turtles on sandbars.
Follow security instructions and speed limit signs when driving across the narrow sluice corridor.

Don’ts

Strong Currents: Never attempt to swim, bathe, or wade into the river near the sluice gates, as undertows and whirlpool currents are lethal.
Do not stop vehicles in the middle of the bridge lanes to take photos, as it triggers immediate highway gridlock.
Do not climb onto the restricted mechanical control towers, gate pulleys, or restricted barrage railings.
Avoid throwing plastic cups, bottles, or food packets over the bridge into the river water.

How to Get There (Transportation Options)

By Highway Road: Koshi Barrage lies directly on the East-West (Mahendra) Highway. Regular long-route buses connecting Kathmandu, Pokhara, Janakpur, Birtamod, and Damak cross directly over the barrage 24/7. Local buses and microbuses run continuously from Inaruwa, Itahari (~35 km), and Rajbiraj (~25 km).

By Air: Fly to Biratnagar Airport (around 55 km east). From the airport, hire a taxi or board a regional bus via Itahari and Inaruwa to arrive at the barrage within 1.5 hours.

Via Chatara Bypass: If traveling via the northern inner-Terai belt, use the paved Chatara Koshi Bridge corridor to bypass the barrage highway during peak holiday rush.

Important Contacts & Emergency Help Desk

Local Administrative Offices and Emergency Support:

Koshi Rural Municipality Office: Laukahi, Sunsari (Website: koshimun.gov.np)
District Police Office Sunsari (Inaruwa): 100 / 025-560199
Area Police Post Koshi Barrage (Bhardaha/Setu): 025-560114 / 100
District Police Office Saptari (Rajbiraj): 031-520199
Koshi Tappu Wildlife Reserve Warden Office: Kusaha (Phone: 025-690302)
Tourist Police Helpline: Dial 1144 (Toll-Free)

Frequently Asked Questions (FAQs)

How many gates does the Koshi Barrage have?

The Koshi Barrage features a total of 56 hydraulic sluice control gates that regulate the river flow across the border corridor.

Why is the Koshi River called the Sorrow of Bihar?

It earned the name because unchecked monsoon flooding historically inundated over 21,000 square kilometers of farmland in northern Bihar, sweeping away homes and crops.

Is there another bridge over the Koshi River nearby?

Yes, the modern Chatara Koshi Bridge is located upstream near Barahakshetra, offering a smooth alternative crossing along the Madan Bhandari Highway.

Image & Media Credits

Image & Content Sources: Nepal Tourism Hub Documentation Team, Department of Water Resources & Local Community Contributors

सूचना तथा सुझाव अनुरोध

यस ऐतिहासिक ब्यारेज तथा महत्त्वपूर्ण ट्रान्जिट गन्तव्यको विवरणलाई अझ प्रभावकारी र तथ्यपरक बनाउन कुनै थप जानकारी वा सुझाव भएमा कृपया हामीलाई सिधै सम्पर्क गरी सहयोग गरिदिनुहुन हार्दिक अनुरोध गर्दछौं।

सुझाव पठाउनुहोस्

Sort By

Ritu Jha
Imported Log in to Reply

Speed

Quality

Price

Huge river expansion with cool breeze over the barrage. Famous for roadside fish delicacies and watching river dolphins during monsoon.

2 months ago
Santosh Yadav
Imported Log in to Reply

Speed

Quality

Price

Saptakoshi river ko 56 gates bhayeko massive barrage. Fresh Koshi fish khana ra wide blue river sunset herna Highway traveler ko iconic stop.

3 months ago
Kashi Garden
Log in to Reply

Accessibility & Reach

Scenic & Cultural Value

Facilities & Cleanliness

There are some rooms for improvements though it’s very beautiful and have scenic views.

2 months ago

Cancel reply

You must be logged in to post a comment.

🎉 Festive Season Partner Special

Own a Hotel, Resort, Cafe, Restaurant, Homestay, Lodge, or Trek Agency Near This Location?

List your business on Nepal Tourism Hub to get discovered instantly by travelers visiting this area. Keep 100% of your booking revenue with zero middleman commissions.

✓ Free Festive Listing

✓ Direct Traveler Contacts

✓ 0% Commission

Add Business Listing → Submit Destination

📢 Want to Place a Featured Banner Ad?

Link directly to your product, services, or booking page on our platform.

Connect via WhatsApp 💬

Create & Explore Tourism Destinations Around Nepal

Koshi Barrage (कोशी ब्यारेज)

Explore Local Stories & Expert Travel Guides

Koshi Barrage (कोशी ब्यारेज)

Claim "Koshi Barrage (कोशी ब्यारेज)"

Explore Local Stories & Expert Travel Guides

Sign In..

Sign up to create your account