The Canadian Hydrographic Service Central and Arctic Region

The Tides Currents and Water Levels Section is a unit within the Technical Services Division. The Section is responsible for the collection of tide, current and water level information in support of CHS hydrographic survey and charting responsibilities and of marine navigation in the region. The Section operates a permanent network of tide and water level gauging stations throughout the Great Lakes, Hudson Bay and the Arctic.

To the left of this screen are links to some of the data and information products available from this unit. If more detailed information is required, please contact :

Toll Free:
1-877-CHS-LINK (877-247-5465)

or by e-mail at

Committee This symbol is used throughout these pages to indicate data or references prepared under the auspices of the binational Coordinating Committee on Great Lakes Basic Hydraulic and Hydrologic Data.

the GLIN                  hydrology section Looking for the latest data on water levels in the Great Lakes? Don't miss the new hydrology section on the Great Lakes Information Network. Thanks to a partnership between the Great Lakes Commission and the Coordinating Committee on Great Lakes Basic Hydraulic and Hydrologic Data, the GLIN hydrology section has been greatly enhanced to provide a centralized means to access hydrology information from the many different agencies responsible for its collection and dissemination. Interactive maps provide the most recent water levels data for the different gauging stations; some as often as every six minutes. The site also links to forecasted and historical data, and includes overviews on various hydrologic topics from experts on the Coordinating Committee.

Great Lakes-St. Lawrence Hydrology

Water Levels