Latest Bulletins

  • Frequently Asked Questions 2019

    Posted on Thursday, October 24, 2019

    We are providing a series of answers to questions that were often asked during the spring flood of 2019. In the weeks to come, we will continue our review of the 2019 spring flood and will be preparing a summary document similar to the document we had prepared following the 2017 flood.

    Frequently Asked Questions 2019

     

    Posted by Ottawa River Regulation Secretariat

  • Open house sessions in the Outaouais Region for those interested in knowing more about river flow and reservoirs management

    Posted on Wednesday, October 23, 2019

    Are you interested in knowing more about the management of flows and reservoirs in the Outaouais Region? Experts in this field will be available to meet with you at several open house sessions that are organized by Hydro-Québec in partnership with the Ottawa River Regulation Planning Board:

    • on November 4th at L’île-du-Grand-Calumet (more info)
    • on November 5th at Campbell’s Bay (more info)
    • on November 6th at Gatineau, Aylmer and Hull areas (more info)
    • on November 7th at Gatineau, Masson-Angers and Buckingham areas (more info)
    • on November 11th at Grenville (more info)
    • on November 12th at Chelsea (more info)
    • on November 13th at Saint-André d’Argenteuil (more info)

     

    Posted by Ottawa River Regulation Secretariat

  • Lowered water levels on the Ottawa River between Hull and the Carillon dam

    Posted on Tuesday, October 15, 2019

    In the coming weeks, Hydro-Québec will carry out drilling work downstream of the Carillon generating station spillway. The river’s upstream water level was lowered by about 25 cm to allow for the work to be carried out. This decrease, combined with low precipitation in recent weeks, has resulted in a lower-than-normal water levels in the Ottawa River for this time of the year.

    The work consists of drilling in the riverbed in front of the spillway and is a common aspect of managing a facility such as the Carillon generating station. The water level in the river must be lowered to ensure a safe work environment for our employees.

    We will be lowering the water level once again in the Ottawa River between October 15 and November 1 on weekdays.  On the weekends, it will return to seasonal norms.  The drilling work will be finished by November 1.

    The current level of the Ottawa River is already 10 to 12 cm lower than the average seen over the past 10 years. This is primarily due to lower precipitation recorded in western Québec since the summer. We recommend that river users and boaters exercise caution when on the river.

    For information:

    Please call our Info-project line and leave us a message

    1 800 465-1521, ext. 6022

    Posted by Hydro-Québec

  • 2019 Spring Flood – Tables of Forecast Peak Levels

    Posted on Thursday, July 11, 2019

    From April 19th to June 7th the ORRS placed on the ORRPB website a table of forecast peak levels for multiple sites along the river with a general description of expected river conditions within the basin. This document was used by agencies and citizens to prepare for expected flood peaks. The 64 tables have now been consolidated into one document, which is available at http://www.ottawariver.ca/current-press-releases.php .

    Posted by Ottawa River Regulation Secretariat

  • Limits to the Regulation of the Ottawa River – 2019 Spring Flood Overview

    Posted on Thursday, July 11, 2019

    The following presentations were made by the Ottawa River Regulation Secretariat at recent public meetings:

    2019-07-04 – Mattawa Public Meeting

    2019-07-09 – Constance Bay Public Meeting

    Posted by Ottawa River Regulation Secretariat

  • Limits to the Regulation of the Ottawa River – 2019 Spring Flood Overview

    Posted on Friday, June 28, 2019

    The following presentations were made by the Ottawa River Regulation Secretariat at recent public meetings.

    June 22 – Pembroke Public Meeting

    June 23 – Westmeath Public Meeting

    June 23 – Arnprior Public Meeting

    Posted by Ottawa River Regulation Secretariat

  • Des Joachims – Refill Strategy

    Posted on Friday, May 31, 2019

    With inflows on the decline, the current strategy at Des Joachims will be to raise water levels approximately 5-10 cm per day over the next two weeks and refill towards an elevation of 152.00 m.

    Posted by Ontario Power Generation

  • Seasonal water level regulation on the Ottawa River

    Posted on Sunday, May 12, 2019

    Ottawa-River-Graph-Freshet-2019

    Posted by Ontario Power Generation

  • Background on OPG operations on the upper Ottawa River during High Flow Water Conditions

    Posted on Sunday, May 12, 2019

    Upper Ottawa River Update
    Renfrew – OPG understands that high water is a concern for communities located along the Upper Ottawa River who are experiencing flooding this spring. High amounts of rainfall plus significant snow pack have resulted in very high water levels within the river system. OPG has been working closely with municipalities and organizations including the Ottawa River Regulatory Planning Board, the Ministry of Natural Resources and Forestry and local conservation authorities on water management. OPG is doing everything we can to mitigate impacts from these events. Public Safety remains our top priority.

    In the spring, the amount of runoff increases causing lakes and rivers to swell, which naturally increases the water levels throughout the river system. The speed of the river is partially determined by the slope, where as the steeper slope allows the water to flow faster. As the water levels increase and rivers widen, so too does the speed at which the river flows. The combined increase of water elevation, volume and speed create a significant gradient/slope in the river and therefore the river’s profile becomes much steeper from one dam to another in the system.

    In relation to the conditions observed within the area of Otto Holden and Mattawa, it should be noted that many of the facilities on the Ottawa River have a limited holding capacity. At certain times of the year, the upstream reservoir does not have sufficient storage to hold upstream water as it arrives at the station. Presently this is the case at the Otto Holden generating station as at this time it must pass the upstream flows from the Timiskaming area.

    While the flow rate within the river can be relatively constant over a specific timeframe, the cross-sectional area will vary throughout the river as the elevation and width changes. Water speed will also vary due to irregularities caused by rocks and the existence of natural gradients, i.e. variation in the slope of the river.

    Due to the characteristics within a river that are applicable to variations of gradient/slope, depth, width and restrictions, a backwater effect can occur over several kilometres and extend upwards of more than fifty kilometres. Backwater occurs when the flow of a river slows due to reaching a narrow section, flat area or obstruction. Under very high flow conditions water begins to ‘pile up’ raising upstream water levels. Within the reach between the Otto Holden G.S and Des Joachims G.S (near Rolphton, ON) facilities, a natural restriction exists from Mattawa to Klock. During spring periods where high water flows exist, this backwater effect will extend upstream to Mattawa.

    OPG strategically maintains a lower elevation at the Des Joachims dam in order to minimize this effect. In doing so, the elevation at Deux Rivières is low and thus the gradient/slope maximized across the reach from Otto Holden GS to Des Joachims. Simply stated, as the river flow increases, OPG maintains a low elevation at Des Joachims to minimize flooding upstream into the Mattawa area. Maintaining lower water levels limits the amount of backwater effect created and subsequently assists to provide upstream flood mitigation. Once river flow declines to a point where the natural rapids no longer creates a “backwater effect” that places Mattawa at risk of flooding, OPG will raise the water levels at Des Joachims to the typical operating levels.

    The Upper Ottawa River is expected to stabilize and the water will return to its natural level in the summer.

    Go to Seasonal water level regulation on the Ottawa River message for additional details.

    Posted by Ontario Power Generation

  • HISTORIC FLOOD RISK ON THE OTTAWA RIVER: Abitibi-Timiskaming region and Mattawa down to Lac Deschenes

    Posted on Thursday, May 9, 2019

    OTTAWA/GATINEAU, Thursday May 9, 2019 — The Ottawa River Regulating Committee warns that most reservoirs in the Abitibi-Timiskaming region are now filled and that excess waters from these areas are now flowing through the downstream river system. With significant rainfall of 25 to 45 mm forecast to begin today over much of the watershed, water levels on the Ottawa River between Mattawa and Lac Deschenes are expected to continue to increase over the next few days and reach a peak that may exceed previous historic record levels. People living along the Ottawa River are encouraged to closely follow changing conditions and to take necessary measures. The Regulating Committee will be reassessing forecast conditions and providing hydrological condition updates on its website daily at http://www.ottawariver.ca/forecast.php. Read the full press release on the webpage «Documentation – Current Press Releases ».

    Posted by Ottawa River Regulation Secretariat

  • ONGOING FLOOD RISK ON THE OTTAWA RIVER Mattawa down to the Montreal Archipelago

    Posted on Friday, May 3, 2019

    OTTAWA/GATINEAU, Friday May 3, 2019 — The Ottawa River Regulating Committee warns that levels and flows on the Ottawa River from Mattawa down to Lac Coulonge are expected to increase again and reach another peak over the next week. Reservoirs in the Abitibi-Timiskaming area are filling rapidly with snowmelt and runoff from precipitation in that part of the watershed. Water released from the reservoirs is increasing and will cause water levels on the Ottawa River downstream between Mattawa and Lac Coulonge to increase. Flows and levels could rise rapidly at times between Mattawa and Lac Coulonge and will possibly exceed flood levels experienced earlier last month. People living along the Ottawa River are encouraged to closely follow changing conditions and to take necessary measures. The Regulating Committee will be reassessing forecast conditions and providing hydrological condition updates on its website daily at http://www.ottawariver.ca/forecast.php. Read the full press release on the webpage «Documentation – Current Press Releases ».

    Posted by Ottawa River Regulation Secretariat

  • Preventive measures for the Chute-Bell generating station

    Posted on Thursday, April 25, 2019

    According to studies done by Hydro-Québec, a dam break at Chute Bell will not affect river conditions on the Ottawa River downstream given that the volume of water retained behind the dam is small. Please refer to the press release issued by Hydro-Québec for more information.

    In French only:

    http://nouvelles.hydroquebec.com/fr/communiques-de-presse/1484/par-mesure-pr/

    Posted by Hydro-Québec

  • INCREASED FLOODING RISK ON THE OTTAWA RIVER – Mattawa down to Montreal Region

    Posted on Thursday, April 25, 2019

    OTTAWA/GATINEAU, Thursday April 25, 2019 — The Ottawa River Regulating Committee warns that levels and flows on the Ottawa River from Mattawa down to the Montreal region are expected to exceed flood levels of May 2017 over the coming week end. Flows and levels are expected to rapidly rise over the weekend due to significant forecast rainfall. On Monday or Tuesday, flows and levels are expected to exceed those observed at the height of the May 2017 flood, depending on the amount of precipitation received. All areas along the Ottawa River that were impacted in 2017, and possibly additional areas, are at risk. People living along the Ottawa River are encouraged to closely follow evolving conditions and to take necessary measures. The Regulating Committee will be reassessing forecast conditions and providing hydrological condition updates on its website daily at http://www.ottawariver.ca/forecast.php. Read the full press release on the webpage «Documentation – Current Press Releases ».

    Posted by Ottawa River Regulation Secretariat

  • EXPECTING MAJOR FLOODING ON THE OTTAWA RIVER – Lac Coulonge down to Montreal Region

    Posted on Thursday, April 18, 2019

    OTTAWA/GATINEAU, Thursday April 18, 2019 — The Ottawa River Regulating Committee warns that levels and flows on the Ottawa River from Lac Coulonge down to the Montreal region are expected to rise extremely rapidly starting this Friday due to forecast rainfall and snowmelt runoff. Major flood levels are expected to be exceeded over the weekend.  Later on, flows and levels similar to those observed at the height of the May 2017 flood may be reached depending on the amount of precipitation received. All flood-prone areas along the Ottawa River from Lac Coulonge down to the Montreal Archipelago are at risk. Residents of flood-prone areas are encouraged to closely follow evolving conditions and to take necessary measures. The Regulating Committee will be reassessing forecast conditions and providing hydrological condition updates on its website daily at http://www.ottawariver.ca/forecast.phpRead the full press release on the webpage « Documentation – Current Press Releases ».

    Posted by Ottawa River Regulation Secretariat

  • Expected flooding in flood-prone areas along the Ottawa River

    Posted on Tuesday, April 16, 2019

    OTTAWA/GATINEAU, Tuesday April 16, 2019 — The Ottawa River Regulating Committee cautions that levels and flows on the Ottawa River from Lake Coulonge down to the Montreal region continue to rise due to precipitation received and ongoing snowmelt. With significant rainfall forecasted later this week, levels will exceed minor flood levels over the Easter weekend in flood-prone areas along the Ottawa River at Lake Coulonge, Chats Lake, Britannia / Lac Deschenes, Pointe-Gatineau, Ottawa / Cumberland, Rockland, Thurso and other vulnerable areas down to the Montreal Archipelago.  Based on the current weather forecast, levels could reach those observed during the period from April 18 to April 21, 2017.  They will however remain below the maximum levels that were reached in May 2017.  The Regulating Committee will be reassessing forecast conditions and providing hydrological condition updates on its website daily at http://www.ottawariver.ca/forecast.php.  Read the full press release on the webpage « Documentation – Current Press Releases ».

    Posted by Ottawa River Regulation Secretariat

  • Rising Ottawa River Water Levels

    Posted on Thursday, April 11, 2019

    OTTAWA/GATINEAU, Thursday April 11, 2019 — The Ottawa River Regulating Committee would like to inform watershed residents that levels and flows along the Ottawa River have begun increasing with the onset of the spring freshet period. It cautions residents along the shores of the Ottawa River, from Mattawa down to the Montreal region that during the spring period water levels can rise rapidly and cause minor flooding in low-lying areas. Based on the current snow cover, the Regulating Committee anticipates that the flow volume in the Ottawa River will be higher than average this spring. Further bulletins will be issued if flood risks increase. Read the full press release on the webpage « Documentation – Current Press Releases ».

    Posted by Ottawa River Regulation Secretariat

  • Beginning of Hydrologic Forecast for Spring Freshet 2019

    Posted on Monday, April 8, 2019

    Beginning today, a general four-day forecast will be provided at the following locations:   Ottawa River at Lake Timiskaming, Ottawa River at Pembroke, Lake Coulonge at Fort-Coulonge, Chats Lake at Arnprior, Lake Deschenes at Britannia (Ottawa-Gatineau) and Ottawa River at Carillon. During the spring freshet, forecasts will be updated on most days and will be made available before 4:00 p.m. Check out our Forecast webpage.

    Posted by Ottawa River Regulation Secretariat

  • Des Joachims GS

    Posted on Thursday, April 4, 2019

    The current strategy at Des Joachims is to pass inflow on a daily/weekly basis. The refill towards 151.00 m will start when the inflow increases. Balancing upstream versus downstream flooding may require adjustments to the current refill strategy.

    Posted by Ontario Power Generation

  • Hydro Quebec is preparing for the spring freshet

    Posted on Tuesday, March 5, 2019

    Video available in French only:
    https://www.facebook.com/hydroquebec1944/videos/2252068134856789/

    Posted by Hydro-Québec

  • Ottawa river levels temporarily lowered

    Posted on Tuesday, August 14, 2018

    Press release

    Posted by Hydro-Québec

  • Safety Boom Installations at Bryson Generating Station – Level Fluctuations

    Posted on Tuesday, July 10, 2018

    A press release is available in French only:

    ESTACADES-BRYSON.pdf

    Posted by Hydro-Québec

  • March 29, 2018 : Integrated Reservoir Management – Spring 2018

    Posted on Thursday, March 29, 2018

    Download this presentation to learn more about the integrated management of the principal reservoirs during spring freshets.

    Reservoir_Management_Spring_2018.pdf

    Posted by Ottawa River Regulation Secretariat

  • February 15, 2018 : Ottawa River – 2017 Spring Flood Summary

    Posted on Tuesday, March 27, 2018

    The Ottawa River Regulation Planning Board is pleased to announce the publishing of a special document regarding the 2017 Spring Flood, which is available at the following link:

    www.ottawariver.ca/docs/2017_Spring_Flood_Summary.pdf

    Posted by Ottawa River Regulation Secretariat