Overview
Since October 2003, the Centre d'expertise hydrique du Québec (CEHQ) has been disseminating water level and flow data from certain hydrometric stations operating by telemetry, commonly called "real-time stations".
In addition to this information, it is possible to obtain the complete history of daily (650 stations) and instantaneous (280 stations) water levels and flows measured at the hydrometric stations operated by the Ministère du Développement durable, de l'Environnement et des Parcs (MDDEP), an agent of the Government of Quebec, whether they are closed or open. In addition, monthly statistics (minimum, average, median and maximum) on the hydrometric stations for which validated data exist are available.
Provider’s contact information
Direction de l'expertise hydrique
675, boul. René-Lévesque Est, aile Alexandre-Taschereau, 4e étage
Québec (Québec) G1R 5V7
Phone: 418 521-3993
Fax: 418 643-6900
Email: expertise.hydrique@environnement.gouv.qc.ca
More information can be found at: https://www.environnement.gouv.qc.ca/eau/hydrique-barrage/index.htm (French)
Licensing and citation
The data are made available without any liability and at the user's own risk.
The description of the conditions of use can be found: http://www.cehq.gouv.qc.ca/hydrometrie/historique_donnees/info_validite.htm
“The Centre d'Expertise Hydrique du Québec and its employees assume no responsibility for the use of this data or for any errors it may contain. Furthermore, the CEHQ and its employees cannot be held responsible for any damages, losses or direct or indirect expenses resulting from the use of this data, for any reason whatsoever.”
(Currently French only Nov 2021)
Variable name and units
Historical hydrometric station runoff data are in (m³/s) and can be obtained as
- Daily mean
- Monthly mean
- Monthly median
- Monthly minima
- Monthly maxima
Spatial coverage and resolution
The station network expands over southern and central Quebec. See download page for an overview map.
Temporal coverage and resolution
The available hydrological series contain at least three years of records for a "flow" station and at least one year for a "level" station. The oldest daily data go back to 1910 (daily data) and up to 1997 for the majority of the 280 stations with instantaneous data.
Information about observations (number, homogeneity)
Various data from more than 650 hydrometric stations, of which more than 200 are still in operation, are accessible. Note that some stations are not available online. Please contact CEHQ for information about those stations.
Methodology
DEH/CEHQ operates a network of approximately 230 hydrometric stations, almost all of which transmit data on a continuous basis, 24 hours a day, 7 days a week. Data recorded every 15 minutes by the measuring instruments are transmitted hourly to an integrated telemetry data collection system via a telephone or satellite link. On a daily basis, it is therefore possible to obtain data on water levels or flows, in particular to monitor spring floods or summer droughts, to optimize the management of dams or to know the level of certain bodies of water for outdoor activities.
Information about the technical and scientific quality
For each hydrometric station, a validation date or a message mentioning that all data are preliminary is written in the header of the data file, except for instantaneous data which are not subject to any systematic validation process. Data after this validation date is preliminary, meaning that it has not yet gone through the full-validation process and therefore changes can still be made. It should also be noted that data prior to the validation date may also be subject to change (error detection, periodic data revision, etc.). Users should ensure that they have the most recent data before using it by downloading the data they want from this website. The monthly statistics files contain only data for validated periods.
Note that a monthly statistic is not calculated when:
- five or more data are missing in the month;
- three or more consecutive pieces of data are missing in a month.
Data from active stations are validated and updated. Most recent data provided within a few days of the observations are preliminary until validated.
Limitations and strengths for application in North Canada
CEHQ maintains a comprehensive network of hydrometric stations and provides access to their data free of charge. Validation and quality flags are delivered with the data.
The dataset covers mainly southern Quebec with fewer station in the North. Note that some of the northern stations may not be available over the website.
The watershed contours and other characteristics are also made available.
References to documents describing the methodology and/or the dataset
CEHQ data access web page:
https://www.cehq.gouv.qc.ca/hydrometrie/historique_donnees/index.asp
Other data like watershed contours, flood and drought information as well as real-time data and forecasts can be found at https://www.cehq.gouv.qc.ca/hydrometrie/index.htm
Link to download the data and format of data
Data access page: https://www.cehq.gouv.qc.ca/hydrometrie/historique_donnees/default.asp
Data are in provided as ASCII files.
Publications including dataset evaluation or comparison with other data in Canada
The data from CEHQ have been used in many hydrological studies on a watershed basis. While no global comparison or evaluation is available, the data have been extensively used in the production of the Quebec Hydroclimatic Atlas.
Quebec Hydroclimatic Atlas interactive version:
https://www.cehq.gouv.qc.ca/atlas-hydroclimatique/index.htm
Quebec Hydroclimatic Atlas PDF version 2015 (English): https://www.cehq.gouv.qc.ca/hydrometrie/atlas/Atlas_hydroclimatique_2015EN.pdf