Coalition for Equitable Water Flow

2021 Water Level Summary

At the end of December, the TSW resets its online water levels charts. In order to have a record of the 2021 water levels for all the reservoir and canal lakes, CEWF is making available screen shots from the TSW website as of the end of December 2021. These include the actual 2021 water level data as well as the multi-year average and historic extremes. The summary charts are organized alphabetically within each sub-watershed as per the Key Map.

To view the summary for 2021 - click here

(Note: this information will remain accessible under 'TSW Water Levels’ on right hand side of the CEWF website homepage. As you can see there are now 8 years of data available for comparison purposes).

Happy New Year from CEWF!

TSW Water Level Management Update - Dec 20/21

Trent-Severn Waterway - Water Level Management Update – Monday, December 20, 2021

Weather

The weather forecast for early next week is changing significantly from day to day. A 20 to 30 mm of mixed precipitation event is forecasted across the next 5 days. 

Outlook

Precipitation amounts for September to December 2021 have contributed to 100-125 % more precipitation relative to normal.  Rainfall and warm temperatures earlier in the month have generated active snowmelt, which, in combination with the above-normal precipitation amounts, resulted in raising the flows and water levels across the watersheds.  With currently forecasted air temperatures below zero, water levels and outflows are expected to crest and slowly recede at all locations. However, there is a measure of uncertainty associated with this.  Depending on the exact amounts of precipitation over the next 5 days, whether it falls as rain or snow and whether air temperature is above or below zero, local snowmelt and snowmelt runoff may occur, impacting the watershed response. Trent Severn Water Management team will be active, and the changing conditions will be closely monitored. Any watershed conditions updates will be released by your Conservation Authority or local Ontario Ministry of Natural Resources district. 

Ice on shorelines

The temperature variations around and above the freezing mark makes ice weak along the shoreline, which is then easily broken and moved by windy conditions. The areas subject to the greatest impact are those facing the primary wind direction. In the event of strong wind conditions, the public should be aware of possible onshore ice movement leading to shoreline damage.

Haliburton and Northern Areas 

All reservoir lakes remain at their respective winter set dam configuration. Water levels on the lakes, in general, are well above average and are beginning to level out. Flows on the Gull River and Burnt River are above average. Central Lakes levels are above average for this time of the year.

Kawartha Lakes and the Otonabee River

After the snowmelt and rainfall of last week, most of the Kawartha Lakes are above average; water levels on the Kawartha Lakes have peaked and are beginning to decline. Flows on the Otonabee River are higher than average for this time of year. 

Rice Lake and the Lower Trent

Rice Lake's water level is above the long-term average and is levelling off. Flows on the Lower Trent River are above average and are beginning to decline. 

Severn River

Lake Simcoe is above the long-term average water level, and outflows have been maximized. Flows on the Black River are above average. Flows on the Severn River are above average.

TSW Drawdown Forecast - Oct 12/21

The drawdown continues on all reservoirs.

To view the TSW Drawdown Forecast for the period covering Oct 12-26, 2021 - click here

Water Levels Remain High for early October

Note - There will be no drawdown forecast from TSW this week.

As a result of extreme rainfall over the last 4 months water levels remain exceptionally high throughout the Trent River watershed. Most dams in the reservoirs, except for those on the Lower Gull River, are already adjusted to their normal winter set levels in terms of logs in place. However the water levels are still declining as a result of recent rainfall events, and flows are higher than normal. For example, the current flow on the Gull River is 40 CMS (cubic meters per second) vs a normal flow for the date of 18 CMS. On the Burnt River the flow is 26 CMS vs a normal of 10 CMS.

On the main stream of the Gull river the TSW is actively managing flows from Twelve Mile Lake downstream to Balsam lake to pass higher than normal flows. In some cases, extra logs are out of the dams and winter set conditions at those dams will be delayed as water is passed downstream.

The extreme rainfall totals since June have not just impacted the reservoirs but also applied to the whole of the Trent River Basin. As a result the TSW water management team has had a very active summer and fall managing water levels and flows throughout the whole system within normal ranges.

As readers may be aware from news reports the Canal system has recently been closed to navigation downstream from Young’s Point to Trenton due to high water flows. TSW has focused on passing extra flow downstream to Lake Ontario to relieve high levels in the system. This has been an exceptional situation to close the canal in the final weeks of the season. The canal is scheduled to reopen tomorrow for the final 4 days of the season to allow boats to clear the system.

Levels throughout the reservoirs can be expected to continue declining towards normal winter levels with the timing dependent on rainfall amounts. We expect that TSW will post a final drawdown forecast by early next week.

TSW Drawdown Forecast - Sep 27/21

After the heavy rainfall events TSW is managing flows downstream resulting in a slower drawdown for many reservoirs this week. 

To view the two-week forecast covering the period Sep 27 - Oct 11, 2021 - click here

TSW Water Management Update

FROM THE TSW:

Weather

Significant rainfall occurred over past 2 days and resulted in total precipitation over that time period of about 60-100 mm which increased water levels and flows across the system.  Some rainfall forecast is expected today with a potential accumulation of 10-20 mm and higher in the areas of localized thunderstorm activity. 

Outlook

Due to the localized nature of the rain events some areas have received 150% of the normal monthly precipitation in September. The impacts from the above average amounts of precipitation received remain across the system. Flows and levels are above normal for this time of the year across all locations.

Trent Severn Water Management team will be active, and the changing conditions will be closely monitored. Any watershed condition updates will be released by your Conservation Authority or local Ontario Ministry of Natural Resources district.

Haliburton and Northern Areas

Water levels and flows remain high in northern areas. Most lake levels on the Gull River, Burnt River system, and Central Lakes are above average. Lake levels are monitored on a 24 hour basis and water management operations are being conducted based on the current watershed conditions, lake levels, estimated runoff amounts and forecasted rainfall. The flows on Burnt River and Gull River are above average and increasing and are expected to be sustained by the enhanced runoff from precipitation and operations in reservoirs. The flows on the Gull River are above average for this time of year.

TSW Drawdown Forecast - Sep 20/21

To view the two-week TSW drawdown forecast covering the period Sept 20 - Oct 4, 2021 - click here

TSW Drawdown Forecast - Sep 13/21

To view the two-week TSW drawdown forecast covering Sept 13-27 - click here

 

Note that the general rate of drawdown is increasing.

 

On many lakes the projected drawdown over the next two weeks exceeds 30 cm, or 1 foot. With many lakes still above their seasonal averages, TSW is working towards the planned annual low water level by mid-October to accommodate the spawning of our lake trout. 

 

 

TSW Drawdown Forecast - Sep7/21

To view the two-week drawdown forecast covering September 7-21, 2021 - click here

TSW Drawdown Forecast - Aug 29/21

The seasonal drawdown continues with many reservoirs projected to drop by more than 20cms over next two weeks. 

To view the two-week forecast covering Aug 29-Sep 12 - click here