River

Rivière Eastmain

756 km from source to mouth · Canada.

CanadaFlows into James Bay

Follow the river Month by month

SourceMouth

The river and every tributary in its basin, drawn from RiverATLAS (CC BY 4.0).

In numbers

Length

756km

Average flow

1,000m³/s

Basin

46,400km²

Drop

552m

from 552 m to 0 m

Country

The journey

From source to mouth

756 km of river and 15 stops on the way: 0 towns and cities on its banks, dams, bridges and the tributaries that feed it.

552 m0 m

Sourceat 552 m0 km

Lac Fromont24 km²75 km

Lac Hecla15 km²145 km

Rivière Tichégamitributary294 km

Lac Gill0.8 km²443 km

Eastmain Reservoir519 km²503 km

Opinaca Reservoir929 km²557 km

Lac Kasapawatich0.4 km²611 km

James Bayat 0 m756 km

0200400600756 km

0 kmSourceat 552 m
0 kmLac Bréhat14 km²
75 kmLac Fromont24 km²
145 kmLac Hecla15 km²
294 kmRivière Tichégamitributary
443 kmLac Gill0.8 km²
503 kmEastmain Reservoir519 km²
557 kmOpinaca Reservoir929 km²
583 kmLac Kawisapuskaw0.8 km²
587 kmLac Kamisikamach0.5 km²
599 kmEastmain Bridge
611 kmLac Kasapawatich0.4 km²
655 kmChute Island
662 kmChute Talking
686 kmRivière à l'Eau Froidetributary
700 kmLa Pêche Rivertributary
756 kmJames Bayat 0 m

Water level along the river (RiverATLAS; the height is exaggerated). Towns: GeoNames and Wikidata; bridges, dams and tributaries: Wikidata.

Watercourse in Quebec, Canada

At the mouth it carries 1,022 m³/s on average: an Olympic pool every 2.4 seconds. It drops from 552 m to 0 m, 0.7 m per kilometre on average. Its basin covers 46,400 km², about the size of BT. Highest water, with the snowmelt: from May to July; lowest: from January to April. Dams and reservoirs hold back a large share of its water (26% of a year's flow).

Where to start

WaskaganishLargest city on its banks · 1,839 people
Moosonee Airport (YMO)Nearest airport with scheduled flights, 131 km from the cityCar hire at YMT airport (Chibougamau)Discover Cars · Affiliate link
On the water3 ferry piers, marinas, boat rentals and boat ramps along the river (OpenStreetMap)
Kayak and canoe73 put-ins and rapids mapped (OpenStreetMap)
From July to AugustThe best months to visit

Rivière Eastmain, month by month

Highest water: from May to July

Lowest water: from January to April. Freezing months (average below −4 °C): from November to March. Melting snow makes up much of its water. Best months to visit: from July to August.

490

-22°44 mmJan

490

-20°33 mmFeb

490

-13°41 mmMar

490

-4°38 mmApr

1,900

4°55 mmMay

1,900

11°83 mmJun

1,900

14°101 mmJul

1,200

13°102 mmAug

1,300

8°102 mmSep

1,300

2°78 mmOct

970

-6°68 mmNov

690

-17°48 mmDec

Water (estimated flow)Air (average) Rain (mm)Best months

From about 490 m³/s in the lowest month to 1,900 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

Car hire at YMT airport (Chibougamau)Discover CarsSee

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

Rivière Eastmain: the basin in numbers

46,090 km² of land send their water to this river. This is what lives on it.

Heavily regulatedReservoirs can hold 26% of a year's flow: dams shape its seasons.

546people live in the basin
386maverage altitude of the basin
809mmof rain a year (basin average)
-2.9°Caverage air temperature
13.8%covered by lakes
29%permafrost
8.5km³held in reservoirs

What covers the basin

50% Forest

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

Rivière Eastmain: what you find on the way

19DamsEastmain-1, Digue LE-9, Eastmain-1, Digue LE-8A, Eastmain-1, Digue LE-8 and 16 more
14WeirsEastmain-1, Seuil PK-207 and 13 more
3Waterfalls
73Rapids
3Boat ramps

From OpenStreetMap, within 2.2 km of the river. Not mapped is not the same as not there.

Cross-checked with our atlases

Rivière Eastmain 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.

2waterfalls on the riverCascadyas
9lakes on its wayLakeyas
1mountain at the sourcePeakyas

Waterfalls (2)

On the river, by Cascadyas

Chute Islandkm 668
Chute Talkingkm 675

Cascadyas is coming soonOpen Cascadyas ↗

Lakes and reservoirs (9)

Lakes it flows through, by Lakeyas

Lac Bréhatkm 014km²
Lac Fromontkm 7724km²
Lac Heclakm 14815km²
Lac Gillkm 4520.8km²
Eastmain Reservoirkm 513519km²
Opinaca Reservoirkm 568929km²
Lac Kawisapuskawkm 5940.8km²
Lac Kamisikamachkm 5990.5km²

1 more on LakeyasLakeyas is coming soonOpen Lakeyas ↗

Mountains at the source (1)

Within 15 km of the source, by Peakyas

Mont des Cris Perdus12 km away

Open Peakyas ↗

From space

The source and the mouth, seen from orbit

Rivière Eastmain: satellite view of the source — **The source**14 km across

Rivière Eastmain: satellite view of the mouth — **The mouth**29 km across

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

Rivière Eastmain in pictures

Eastmain River Dec 2005 — P199 · CC BY 2.5

Eastmain-River-shoreline-QFJAAWCCC — Daniel Horen Greenford · CC BY-SA 4.0

Eastmain River - panoramio — Rudy_P · CC BY 3.0

Riviere-eastmain — Jean-Marc Trepanier · CC BY-SA 3.0

Tributaries

Where it flows, and what flows into it

Tributaries (6)

Also: Rivière Opinaca, La Pêche River, Rivière Saffray, Rivière à l'Eau Froide, Rivière Tichégami, Rivière Misask

Nearby

Rivers nearby

Rivière Rupert

Canada763 km900 m³/s84 km away Rivière Nottaway

Canada225 km1,200 m³/s118 km away Harricana River

Canada533 km570 m³/s152 km away Albany River

Canada832 km1,400 m³/s214 km away Abitibi River

Canada540 km320 m³/s215 km away Attawapiskat River

Canada748 km630 m³/s275 km away Great Whale River

Canada726 km680 m³/s341 km away

Where these numbers come from

Name, length, places	Wikidata (Q1968809) · 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
Our other atlases	Cascadyas, 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?

Same idea, other landscapes: field atlases built on open data, month by month, in seven languages.

beaches

Find your beach: sea temperature, sun and swimming month by month.Visit

lakes

Every lake on Earth: water temperature, ice, depth and the shore.Coming soonVisit

mountains

Every summit in 3D: summit weather, the 0 °C line, huts and trails.Visit

waterfalls Cascadyas

Every waterfall: height, flow month by month and when it roars.Coming soonVisit

islands

Every island from the sea up: size, sea temperature, ferries and 3D.Coming soonVisit

rivers

Every river from source to sea: the journey, the flow and the basin in numbers.You are here

canyons

Every canyon cut to scale: depth to the floor, rim and floor temperatures, trails and viewpoints.Coming soonVisit