Marine Navigation Services - Water Level Information

St. Lawrence Ship Channel

Water Level Forecasts and Information Bulletin (No. 14-16)

Forecasts as of April 17, 2014 for the expected lowest water levels at the indicated stations in the St. Lawrence ship channel.

Expected Lowest Water Level Above Chart Datum
Station3 days
(18/04 - 20/04)
4 to 7 days
(21/04 - 24/04)
Week 2
(25/04 - 01/05)
Week 3
(02/05 - 08/05)
Week 4
(09/05 - 15/05)
Montreal 2.60m 2.20m 2.1m 1.8m 1.5m
Sorel 2.80m 2.30m 2.2m 1.9m 1.7m
Trois-Rivieres 3.10m 2.50m 2.4m 2.1m 1.9m


  1. These forecasts give the expected minimum water levels above chart datum at the indicated locations and at the specified times to assist commercial shipping in short term planning of operations (1 to 4 weeks).
  2. This bulletin is produced by the Hydraulic Engineering sector, CCG, Central and Arctic Region on Thursday of each week during the navigation season.
  3. It should be clearly understood that this information is a forecast of water levels which may be altered by short term hydrometeorological factors. The vessel master or officer-in-charge has the ultimate responsibility for the vessel safety at all times.

Pertinent Current Information

1. Lake Ontario :

Pertinent current information of Lake Ontario
  Level (m)
(Weekly average water level)
Level different from long
term average (m)
(Weekly average water level)
Outflow (m3/s)
(Outflow at the Moses-Saunders dam)
Difference from
previous week
(Outflow at the Moses-Saunders dam)
Last week 74.73 0.15 6500 -200 (-3%)
Current 74.9 0.17 6120 -380 (-6%)

2. Ottawa River Outflow :

Pertinent current information on the Ottawa River Outflow
  Outflow (m3/s)
(Total outflow at the Carillon dam)
Difference from
previous week
(Total outflow at the Carillon dam)
Outflow (m3/s)
(Outflow into Lake St. Louis)
Difference from
previous week
(Outflow into Lake St. Louis)
Last week 2060 800 (63%) 790 360 (84%)
Current 5270 3210 (156%) 2440 1650 (209%)

Additional information may be obtained from :

Frederic Filion, Eng.
Waterways Manager
Canadian Coast Guard
Central and Arctic Region
101 Champlain Blvd
Quebec, Quebec, G1K 7Y7
Phone : (418) 648-7493
Fax : (418) 648-4877