Watershed Updates

Upper Mattagami Watershed Statistics April 17, 2026 Update 150 150 MRCA

Upper Mattagami Watershed Statistics April 17, 2026 Update

Watershed Update – April 17, 2026

  • Generally, snow depth and water content conditions for this time of year are above normal.  Water content variances are 191% to 254% above normal through the entire Upper Mattagami Watershed.
  • Current forecasts over the coming week show daytime temperatures ranging from +9°C to -3°C with ~15mm of precipitation expected over the next 5 to 7 days.
  • Inflows at OPG reservoirs have started to increase while all reservoirs are currently drawn down.
  • Town Creek, Crawford Creek and other area watercourses are flowing well.  All watercourses will continue to be closely watched by Authority and Municipal staff.
  • The next Update will be issued on or about May 5, 2026

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View OPG River System Data / Water Levels and Flow

If you have any questions or comments, please contact the Conservation Authority at 705-360-2660 or via email at [email protected]

See our Upper Mattagami River Watershed Statistics page to download the current watershed statistics and for the full list of reports for 2026.

The information contained in this update has been gathered by Ontario Power Generation, the Ministry of Natural Resources and the Mattagami Region Conservation Authority. The summary highlights dam operations and storages as well as snow depth and water content in comparison to historical norms.  Watershed surveys will be conducted on the 1st and 15th of each month until the snow cover has disappeared. Updates will be issued until such time any flood threat has passed.

Upper Mattagami Watershed Statistics April 2, 2026 Update 150 150 MRCA

Upper Mattagami Watershed Statistics April 2, 2026 Update

Watershed Update – April 2, 2026

  • Generally, snow depth and water content conditions for this time of year are above normal. Water content variances are 130% to 220% above normal through the entire Upper Mattagami Watershed.
  • Current forecasts over the coming week show daytime temperatures ranging from -6°C to +1°C with some mixed precipitation expected over the next 5 to 7 days.
  • Natural inflows across the upper Mattagami watershed are slightly downward, with the exception of Peterlong, in response to the colder overnight temperatures experienced recently. No significant change is anticipated in the short-term forecast, with temperatures hovering around or below 0°C. Snow depth and snow water equivalent continue to increase since the last surveys due to ongoing snowfall. Reservoir drawdowns are nearing completion or have already been completed.
  • The enclosed portions of Town Creek and Crawford Creek are being closely watched by Authority and Municipal staff.
  • The next Update will be issued on or about April 17.

Sign up to have flood alerts sent to your email address.

View OPG River System Data / Water Levels and Flow

If you have any questions or comments, please contact the Conservation Authority at 705-360-2660 or via email at [email protected]

See our Upper Mattagami River Watershed Statistics page to download the current watershed statistics and for the full list of reports for 2026.

The information contained in this update has been gathered by Ontario Power Generation, the Ministry of Natural Resources and the Mattagami Region Conservation Authority. The summary highlights dam operations and storages as well as snow depth and water content in comparison to historical norms.  Watershed surveys will be conducted on the 1st and 15th of each month until the snow cover has disappeared. Updates will be issued until such time any flood threat has passed.

Upper Mattagami Watershed Statistics March 19, 2026 Update 150 150 MRCA

Upper Mattagami Watershed Statistics March 19, 2026 Update

Watershed Update – March 19, 2026

  • Generally, snow depth and water content conditions for this time of year are above normal. Water content variances are 114.7% to 214.6% above normal through the entire Upper Mattagami Watershed.
  • Current forecasts over the coming week show daytime temperatures ranging from -7°C to -1°C over the next 5 to 7 days. Total snowfall amounts over the next few days could amount to 5 to 10 cm, with some precipitation mixed in.
  • Inflows across the upper Mattagami watershed are being held. No significant decrease is anticipated with the forecast varying weather throughout the day. Snow depth and water content have increased significantly since the last surveys due to heavy snow and rain. Drawdowns are nearing completion or completed.
  • The enclosed portions of Town Creek and Crawford Creek are being closely watched by Authority and Municipal staff.
  • The Authority’s Flood Contingency Plan has been distributed to watershed stakeholders.
  • The next Update will be issued on or about April 2.

Sign up to have flood alerts sent to your email address.

View OPG River System Data / Water Levels and Flow

If you have any questions or comments, please contact the Conservation Authority at 705-360-2660 or via email at [email protected]

See our Upper Mattagami River Watershed Statistics page to download the current watershed statistics and for the full list of reports for 2026.

The information contained in this update has been gathered by Ontario Power Generation, the Ministry of Natural Resources and the Mattagami Region Conservation Authority. The summary highlights dam operations and storages as well as snow depth and water content in comparison to historical norms.  Watershed surveys will be conducted on the 1st and 15th of each month until the snow cover has disappeared. Updates will be issued until such time any flood threat has passed.

Upper Mattagami Watershed Statistics March 3, 2026 Update 150 150 MRCA

Upper Mattagami Watershed Statistics March 3, 2026 Update

Watershed Update – March 3, 2026

  • Generally, snow depth and water content conditions for this time of year are above  normal. Water content variances are 105.8% to 156.75% above normal through the entire Upper Mattagami Watershed.
  • Current forecasts over the coming week show daytime temperatures ranging from -11°C to +6°C over the next 5 to 7 days with some minor precipitation expected.
  • Inflows across the watershed are holding above normal range for this time of year. Elevations are on track to meet targets as reservoirs continue with draw down, with the exception being Wawaitin, where reservoir elevation is currently holding until draw down commences in the coming weeks.
  • The enclosed portions of Town Creek and Crawford Creek are being closely watched by Authority and Municipal staff.
  • The Authority’s Flood Contingency Plan has been updated and will be distributed to watershed stakeholders in March.
  • The next Update will be issued on or about March 17.

Sign up to have flood alerts sent to your email address.

View OPG River System Data / Water Levels and Flow

If you have any questions or comments, please contact the Conservation Authority at 705-360-2660 or via email at [email protected]

See our Upper Mattagami River Watershed Statistics page to download the current watershed statistics and for the full list of reports for 2026.

The information contained in this update has been gathered by Ontario Power Generation, the Ministry of Natural Resources and the Mattagami Region Conservation Authority. The summary highlights dam operations and storages as well as snow depth and water content in comparison to historical norms.  Watershed surveys will be conducted on the 1st and 15th of each month until the snow cover has disappeared. Updates will be issued until such time any flood threat has passed.

Upper Mattagami Watershed Statistics May 16, 2025 Update 150 150 MRCA

Upper Mattagami Watershed Statistics May 16, 2025 Update

Watershed Update – May 16 2025

  • The majority of snow course sampling sites were absent of snow and the consensus among the surveying organizations is that no further snow course sampling is expected.
  • Current forecasts over the coming week show daytime temperatures ranging from +8°C to +24°C with minimal precipitation expected over the next 5 to 7 days.
  • Further Updates will be issued as required.

Sign up to have flood alerts sent to your email address.

View OPG River System Data / Water Levels and Flow

If you have any questions or comments, please contact the Conservation Authority at 705-360-2660 or via email at [email protected]

See our Upper Mattagami River Watershed Statistics page to download the current watershed statistics and for the full list of reports for 2025.

The information contained in this update has been gathered by Ontario Power Generation, the Ministry of Natural Resources & Forestry and the Mattagami Region Conservation Authority. The summary highlights dam operations and storages as well as snow depth and water content in comparison to historical norms.  Watershed surveys will be conducted on the 1st and 15th of each month until the snow cover has disappeared. Updates will be issued until such time any flood threat has passed.

Upper Mattagami Watershed Statistics May 2, 2025 Update 150 150 MRCA

Upper Mattagami Watershed Statistics May 2, 2025 Update

Watershed Update – May 2 2025

  • Generally, snow depth and water content conditions for this time of year are above normal. Water content variances are 235% to 314% above normal through the entire Upper Mattagami Watershed. The Shining Tree site is almost devoid of snow.
  • Current forecasts over the coming week show daytime temperatures ranging from +7°Cto +19°C with minimal precipitation expected over the next 5 to 7 days.
  • The next Update will be issued on or about May 15, 2025.

Sign up to have flood alerts sent to your email address.

View OPG River System Data / Water Levels and Flow

If you have any questions or comments, please contact the Conservation Authority at 705-360-2660 or via email at [email protected]

See our Upper Mattagami River Watershed Statistics page to download the current watershed statistics and for the full list of reports for 2025.

The information contained in this update has been gathered by Ontario Power Generation, the Ministry of Natural Resources & Forestry and the Mattagami Region Conservation Authority. The summary highlights dam operations and storages as well as snow depth and water content in comparison to historical norms.  Watershed surveys will be conducted on the 1st and 15th of each month until the snow cover has disappeared. Updates will be issued until such time any flood threat has passed.

Upper Mattagami Watershed Statistics April 16, 2025 Update 150 150 MRCA

Upper Mattagami Watershed Statistics April 16, 2025 Update

Watershed Update – April 16, 2025

  • Generally, snow depth and water content conditions for this time of year are above normal.  Water content variances are 133% to 177% above normal through the entire Upper Mattagami Watershed.
  • Current forecasts over the coming week show daytime temperatures ranging from +1°C to +8°C with 25mm of precipitation expected over the next 5 to 7 days.
  • Inflows at OPG reservoirs have started to increase while all reservoirs are currently drawn down.
  • Town Creek, Crawford Creek and other area watercourses are flowing well.  All watercourses will continue to be closely watched by Authority and Municipal staff.
  • The next Update will be issued on or about May 5, 2025.

Sign up to have flood alerts sent to your email address.

View OPG River System Data / Water Levels and Flow

If you have any questions or comments, please contact the Conservation Authority at 705-360-2660 or via email at [email protected]

See our Upper Mattagami River Watershed Statistics page to download the current watershed statistics and for the full list of reports for 2025.

The information contained in this update has been gathered by Ontario Power Generation, the Ministry of Natural Resources & Forestry and the Mattagami Region Conservation Authority. The summary highlights dam operations and storages as well as snow depth and water content in comparison to historical norms.  Watershed surveys will be conducted on the 1st and 15th of each month until the snow cover has disappeared. Updates will be issued until such time any flood threat has passed.

Upper Mattagami Watershed Statistics April 3, 2025 Update 150 150 MRCA

Upper Mattagami Watershed Statistics April 3, 2025 Update

Watershed Update – April 3, 2025

  • Generally, snow depth and water content conditions for this time of year are above normal.  Water content variances are 139% to 191% above normal through the entire Upper Mattagami Watershed.
  • Current forecasts over the coming week show daytime temperatures ranging from -6°C to +7°C with some mixed precipitation expected over the next 5 to 7 days.
  • Inflows at OPG reservoirs are currently holding at slightly higher than normal levels while reservoirs are continuing to be drawn down.
  • Portions of Town Creek, Crawford Creek and other area watercourses are flowing well.  All watercourses will continue to be closely watched by Authority and Municipal staff.
  • The next Update will be issued on or about April 17.

Sign up to have flood alerts sent to your email address.

View OPG River System Data / Water Levels and Flow

If you have any questions or comments, please contact the Conservation Authority at 705-360-2660 or via email at [email protected]

See our Upper Mattagami River Watershed Statistics page to download the current watershed statistics and for the full list of reports for 2025.

The information contained in this update has been gathered by Ontario Power Generation, the Ministry of Natural Resources & Forestry and the Mattagami Region Conservation Authority. The summary highlights dam operations and storages as well as snow depth and water content in comparison to historical norms.  Watershed surveys will be conducted on the 1st and 15th of each month until the snow cover has disappeared. Updates will be issued until such time any flood threat has passed.

Upper Mattagami Watershed Statistics March 19, 2025 Update 150 150 MRCA

Upper Mattagami Watershed Statistics March 19, 2025 Update

Watershed Update – March 19, 2025

 

  • Generally, snow depth and water content conditions for this time of year are above normal. Water content variances are 101.5% to 126.7% above normal through the entire Upper Mattagami Watershed.
  • Current forecasts over the coming week show daytime temperatures ranging from -9°C to +6°C over the next 5 to 7 days. Total snowfall amounts over the next few days could amount to 20 to 40cm, with some precipitation mixed in.
  • Inflows across the Upper Mattagami watershed slightly increased since the last report due to rain and above average temperatures. Inflows are currently holding at slightly higher than normal levels but are anticipated to decrease with the return to cooler weather. Reservoirs are currently being drawn down.
  • The enclosed portions of Town Creek and Crawford Creek are being closely watched by Authority and Municipal staff.
  • The Authority’s Flood Contingency Plan has been distributed to watershed stakeholders.
  • The next Update will be issued on or about April 2.

Sign up to have flood alerts sent to your email address.

View OPG River System Data / Water Levels and Flow

If you have any questions or comments, please contact the Conservation Authority at 705-360-2660 or via email at [email protected]

See our Upper Mattagami River Watershed Statistics page to download the current watershed statistics and for the full list of reports for 2025.

The information contained in this update has been gathered by Ontario Power Generation, the Ministry of Natural Resources & Forestry and the Mattagami Region Conservation Authority. The summary highlights dam operations and storages as well as snow depth and water content in comparison to historical norms.  Watershed surveys will be conducted on the 1st and 15th of each month until the snow cover has disappeared. Updates will be issued until such time any flood threat has passed.

Upper Mattagami Watershed Statistics March 6, 2025 Update 150 150 MRCA

Upper Mattagami Watershed Statistics March 6, 2025 Update

Watershed Update – March 6, 2025

  • Generally, snow depth and water content conditions for this time of year are above and below normal, depending on the station.  Water content variances are 73.3% to 140.5% when compared to normal through the entire Upper Mattagami Watershed.
  • Current forecasts over the coming week show daytime temperatures ranging from -10°C to +1°C over the next 5 to 7 days with some minor precipitation expected.
  • Inflows across the watershed are holding within the normal range for this time of year.  Elevations are on track to meet targets as reservoirs continue with draw down, with the exception being Wawaitin, where reservoir elevation is currently holding until draw down commences in the coming weeks.
  •  The enclosed portions of Town Creek and Crawford Creek are being closely watched by Authority and Municipal staff.
  •  The Authority’s Flood Contingency Plan has been updated and will be distributed to watershed stakeholders in March.
  • The next Update will be issued on or about March 18.

Sign up to have flood alerts sent to your email address.

View OPG River System Data / Water Levels and Flow

If you have any questions or comments, please contact the Conservation Authority at 705-360-2660 or via email at [email protected]

See our Upper Mattagami River Watershed Statistics page to download the current watershed statistics and for the full list of reports for 2025.

The information contained in this update has been gathered by Ontario Power Generation, the Ministry of Natural Resources & Forestry and the Mattagami Region Conservation Authority. The summary highlights dam operations and storages as well as snow depth and water content in comparison to historical norms.  Watershed surveys will be conducted on the 1st and 15th of each month until the snow cover has disappeared. Updates will be issued until such time any flood threat has passed.