River
Sekong River
475 km from source to mouth · Cambodia, Laos and Vietnam.
Cambodia, Laos and VietnamFlows into Tonlé San1st longest in Cambodia
In numbers
Length
475km
Average flow
5,400m³/s
Basin
28,792km²
Drop
289m
from 337 m to 48 m
Countries
3
The journey
From source to mouth
475 km of river and 3 stops on the way: 2 towns and cities on its banks, dams, bridges and the tributaries that feed it.
- 0 kmSourceat 337 m
- 139 kmSekong20,116 people
- 228 kmAttapeu4,297 people
- 467 kmSekong Bridge
- 475 kmTonlé Sanat 48 m
Water level along the river (RiverATLAS; the height is exaggerated). Towns: GeoNames and Wikidata; bridges, dams and tributaries: Wikidata.
River in Vietnam, Laos and Cambodia
At the mouth it carries 5,400 m³/s on average: 2.2 Olympic pools every second. It drops from 337 m to 48 m, 0.6 m per kilometre on average. Its basin covers 28,792 km², about the size of AL. 326,000 people live in it. Highest water: from August to September; lowest: from January to April. No large dam holds it back: it is one of the world's free-flowing rivers.
Where to start
- SekongLargest city on its banks · 20,116 people
- Pakse International Airport (PKZ)Nearest airport with scheduled flights, 104 km from the cityCar hire in Ubon RatchathaniDiscover Cars · Affiliate link↗
- On the water17 ferry piers, marinas, boat rentals and boat ramps along the river (OpenStreetMap)
- From November to FebruaryThe best months to visit
Sekong River, month by month
Highest water: from August to September
Lowest water: from January to April. Best months to visit: from November to February.
From about 140 m³/s in the lowest month to 2,800 m³/s in the highest. An estimate: the monthly flow is modelled from the lowest and highest months of WaterGAP (RiverATLAS, 1971–2000) and the rain and snow along the river (WorldClim). Dams change the real rhythm. The chip is the average air temperature; below it, the month's rain.
Plan the trip
Plan the trip: boat trips, a bed by the river, a car
Some links above are affiliate links: if you book through them we may earn a commission, at no extra cost to you. It never changes what the data on this page says.
The basin
Sekong River: the basin in numbers
28,792 km² of land send their water to this river. This is what lives on it.
- 326,000people live in the basin
- 12/km²people per km²
- 558maverage altitude of the basin
- 2,664mmof rain a year (basin average)
- 23.9°Caverage air temperature
- 25%protected areas
- 0.1%covered by lakes
- 0.6km³held in reservoirs
What covers the basin
- 59% Forest
- 2% Cropland
- 5% Pasture
RiverATLAS (HydroATLAS v1.0, CC BY 4.0): land cover, people, protected areas, glaciers and dams over the whole basin upstream of the mouth.
Along the river
Sekong River: what you find on the way
- 1WaterfallsTad Faek
- 17Ferry piers
From OpenStreetMap, within 2.1 km of the river. Not mapped is not the same as not there.
From space
The source and the mouth, seen from orbit
Sentinel-2 cloudless 2016 by EOX IT Services GmbH (contains modified Copernicus Sentinel data 2016), CC BY 4.0. The glowing line is the river as drawn by RiverATLAS.
Photos
Sekong River in pictures
Tributaries
Where it flows, and what flows into it
It flows into
Tonlé SanCambodia372 km2,900 m³/sTributaries (1)
Also: Xe Kaman River
ThailandWhere these numbers come from
| Name, length, places | Wikidata (Q2228176) · CC0 |
|---|---|
| Course, profile, basin | RiverATLAS v1.0 (HydroATLAS, Linke et al. 2019) · CC BY 4.0 — followed from the source to the mouth given by Wikidata |
| Flow | WaterGAP (RiverATLAS), 1971–2000 · CC BY 4.0 |
| Climate along the river | WorldClim (RiverATLAS), 1970–2000 · CC BY 4.0 |
| Towns, bridges, dams | Wikidata · CC0; GeoNames · CC BY 4.0 |
| Along the river | © OpenStreetMap contributors · ODbL |
| Images | EOX Sentinel-2 cloudless 2016 · CC BY 4.0; Wikimedia Commons |
Every source and licence is on the data sources page.
The family
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