River
Mahakam River
940 km from source to mouth · Indonesia.
IndonesiaFlows into Makassar Strait2nd longest in Indonesia
In numbers
Length
940km
Average flow
300m³/s
Basin
80,000km²
Drop
498m
from 498 m to 0 m
Country
1
The journey
From source to mouth
940 km of river and 8 stops on the way: 3 towns and cities on its banks, dams, bridges and the tributaries that feed it.
- 0 kmSourceat 498 m
- 629 kmLake Jempang124 km²
- 691 kmTanjung Sarai Lake3.2 km²
- 698 kmKenohan Semayang105 km²
- 827 kmKutai Kartanegara Bridge
- 854 kmLoa Janan212,816 people
- 864 kmMahakam Bridge
- 868 kmSamarinda831,460 people
- 896 kmMuarajawa13,182 people
- 940 kmMakassar Straitat 0 m
Water level along the river (RiverATLAS; the height is exaggerated). Towns: GeoNames and Wikidata; bridges, dams and tributaries: Wikidata.
River in East Kalimantan, Indonesia
At the mouth it carries 300 m³/s on average: an Olympic pool every 8.3 seconds. It drops from 498 m to 0 m, 0.5 m per kilometre on average. Its basin covers 80,000 km², about the size of CZ. 1.5 million people live in it. Highest water: from December to January and from April to May. No large dam holds it back: it is one of the world's free-flowing rivers.
Where to start
- SamarindaLargest city on its banks · 831,460 people
- Aji Pangeran Tumenggung Pranoto International Airport (AAP)Nearest airport with scheduled flights, 18 km from the cityCar hire at DPS airport (Kuta, Badung)Discover Cars · Affiliate link↗
- On the water51 ferry piers, marinas, boat rentals and boat ramps along the river (OpenStreetMap)
- From January to February and from June to AugustThe best months to visit
Mahakam River, month by month
Highest water: from December to January and from April to May
Best months to visit: from January to February and from June to August.
From about 2,100 m³/s in the lowest month to 3,500 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
Mahakam River: the basin in numbers
76,429 km² of land send their water to this river. This is what lives on it.
- 1.5millionpeople live in the basin
- 20/km²people per km²
- 338maverage altitude of the basin
- 2,922mmof rain a year (basin average)
- 24.9°Caverage air temperature
- 4%protected areas
- 0.5%covered by lakes
What covers the basin
- 54% Forest
- 17% Cropland
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
Mahakam River: what you find on the way
- 30Ferry piersPenyeberangan Loa Pari, Samarinda and 28 more
- 21MarinasDermaga Long Iram, Pelabuhan Tering, Pelabuhan Melak and 18 more
From OpenStreetMap, within 2.3 km of the river. Not mapped is not the same as not there.
Cross-checked with our atlases
Mahakam River 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.
3lakes on its wayLakeyas
2mountains at the sourcePeakyas
6islands off the mouthIslandyas
Lakes and reservoirs (3)
Lakes it flows through, by Lakeyas
- Lake Jempangkm 557124km²
- Tanjung Sarai Lakekm 6123.2km²
- Kenohan Semayangkm 617105km²
Lakeyas is coming soonOpen Lakeyas ↗
Mountains at the source (2)
Within 15 km of the source, by Peakyas
- Bukit Lasantuyan10 km away
- Bukit Lasantobong7.3 km away
Islands off the mouth (6)
Within 30 km of the mouth, by Islandyas
- Lalukena Island8.8 km away28km²
- Kerbau Island2.7 km away25km²
- Perangatan Besar Island10 km away22km²
- Kayumajarang Island21 km away19km²
- Muaraulu Island14 km away12km²
- Perangatan Kecil Island16 km away14km²
Islandyas is coming soonOpen Islandyas ↗
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
Mahakam River in pictures
Tributaries
Where it flows, and what flows into it
Tributaries (1)
Also: Lawa River
Nearby
Rivers nearby
Where these numbers come from
| Name, length, places | Wikidata (Q328396) · 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, Islandyas — 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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