River
Nam Ngum
354 km from source to mouth · Laos.
LaosFlows into Mekong River2nd longest in Laos
In numbers
Length
354km
Average flow
670m³/s
Basin
16,808km²
Drop
882m
from 1,034 m to 152 m
Country
1
The journey
From source to mouth
354 km of river and 2 stops on the way: 0 towns and cities on its banks, dams, bridges and the tributaries that feed it.
- 0 kmSourceat 1,034 m
- 180 kmAngkep Nam Ngum437 km²
- 180 kmNam Ngum Dam
- 354 kmMekong Riverat 152 m
Water level along the river (RiverATLAS; the height is exaggerated). Towns: GeoNames and Wikidata; bridges, dams and tributaries: Wikidata.
River in Xiangkhoang Province and Viangchan Prefecture, Laos
At the mouth it carries 668 m³/s on average: an Olympic pool every 3.7 seconds. It drops from 1,034 m to 152 m, 2.5 m per kilometre on average. Its basin covers 16,808 km², about the size of SZ. 618,000 people live in it. Highest water: from August to September; lowest: from December to March. Dams and reservoirs hold back a large share of its water (33% of a year's flow).
Where to start
- RattanawapiA town on its banks
- Wattay International Airport (VTE)Nearest airport with scheduled flights, 70 km from the cityCar hire at VTE airport (Vientiane)Discover Cars · Affiliate link↗
- On the water27 ferry piers, marinas, boat rentals and boat ramps along the river (OpenStreetMap)
- From November to MarchThe best months to visit
Nam Ngum, month by month
Highest water: from August to September
Lowest water: from December to March. Best months to visit: from November to March.
From about 86 m³/s in the lowest month to 1,800 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
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The basin
Nam Ngum: the basin in numbers
16,808 km² of land send their water to this river. This is what lives on it.
- 618,000people live in the basin
- 38/km²people per km²
- 718maverage altitude of the basin
- 2,109mmof rain a year (basin average)
- 22.8°Caverage air temperature
- 6%protected areas
- 2.8%covered by lakes
- 7.0km³held in reservoirs
What covers the basin
- 10% Forest
- 3% Cropland
- 7% Pasture
- 1% Towns and cities
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
Nam Ngum: what you find on the way
- 2Weirs
- 1WaterfallsTad Vangluang
- 26Ferry piers
- 1Marinas
From OpenStreetMap, within 1.9 km of the river. Not mapped is not the same as not there.
Cross-checked with our atlases
Nam Ngum in our other atlases
What our sister atlases know about the waterfalls on this river, the lakes it flows through, the beaches at its mouth, the mountains where it rises and the islands off its mouth.
1lake on its wayLakeyas
2mountains at the sourcePeakyas
Lakes and reservoirs (1)
Lakes it flows through, by Lakeyas
- Angkep Nam Ngumkm 186437km²
Lakeyas is coming soonOpen Lakeyas ↗
Mountains at the source (2)
Within 15 km of the source, by Peakyas
- Phou Douk9.9 km away
- Phu Keng3.1 km away
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.
Tributaries
Where it flows, and what flows into it
It flows into
Mekong River
Vietnam4,350 km15,000 m³/s
CambodiaNearby
Rivers nearby
Laos448 km390 m³/s232 km awayMa RiverVietnam512 km640 m³/s342 km awayChi River
Thailand765 km290 m³/s371 km awayRed RiverVietnam1,149 km900 m³/s434 km awayYom RiverThailand600 km430 m³/s393 km awayMun RiverThailand673 km720 m³/s406 km awayKok RiverLaos285 km2,800 m³/s389 km awayPing RiverThailand800 km260 m³/s418 km awayWhere these numbers come from
| Name, length, places | Wikidata (Q666581) · CC0 |
|---|---|
| Course, profile, basin | RiverATLAS v1.0 (HydroATLAS, Linke et al. 2019) · CC BY 4.0 — followed along the river network from the point 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 |
| Our other atlases | Lakeyas, Peakyas — Wikidata · CC0; © OpenStreetMap contributors · ODbL; GeoNames · CC BY 4.0; HydroLAKES · CC BY 4.0; NOAA OISST |
Every source and licence is on the data sources page.
The family
Do you prefer beaches, lakes, mountains, waterfalls, islands, rivers or canyons?
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