Trent River Watershed Flow Chart

Here is an interesting flowchart showing how all the TSW lakes are connected.

Note that area lakes Jack, Anstruther, and Eels are all TSW reservoir lakes.

It is true that Chandos Lake flows into the Crowe River, and that the Crowe River eventually enters the Trent River near Campbellford. There is a dam on the Crowe River at Marmora, that primarily controls the level of Crowe Lake. The operation of this dam has negligible effect on Chandos because the difference in elevations is about 130 metres, and between Chandos Lake and Crowe Lake there are many natural areas (wetlands, etc), to store water.

Low Water Everywhere!!

Iain Gorman forwarded me some correspondence he received regarding low lake levels in the region.

It is duplicated below, in Italics,

First though, an explainer….

TSW is the “Trent Severn Waterway”, that connects Lake Ontario to Georgian Bay

CEWF is “The Coalition for Equitable Water Flow”. It is a coalition of 32 Member Lake Associations (does not include CLPOA) which represents 91% of the Trent Severn Waterway’s (TSW’s) reservoir lake storage capacity and covers the sub-watersheds of the Gull, Burnt & Mississauga rivers plus Nogies, Eel’s & Jack’s creeks. In total, the Coalition represents the interests of 35,000+ shoreline property owners in the “Haliburton Sector” of the Trent watershed, which includes 35 reservoir and several flow-through (RaFT) lakes in Haliburton County and northern Peterborough County. The purpose is to provide an integrated approach to the management of lake levels. All these lakes are essentially “reservoir lakes”, that are used to maintain navigation levels in the Trent Severn Waterway. So draining any particular lake needs to be done “equitably”.

We are fortunate that Chandos is an unregulated lake (no dam), and is in the Crowe Valley watershed.

Here is Iain’s note:
LOW WATER LEVELS: (From Algonquin Highlands Mayor Carol Moffatt)

Egads! I’ve checked in with our friends at CEWF for details beyond what I know and:
* TSW last week added logs to many dams to capture the expected rainfall and runoff but if you were comparing your weather app with your weather window this weekend you know we didn’t get what was forecast;
* There’s been a 50% shortfall in spring rains so far with temperatures above normal;
* The freshet was almost non-existent, certainly in comparison with recent years!
* There have been some inconsistencies in usual runoff patterns meaning how lakes usually fill up isn’t happening;
* TSW captured the snowmelt runoff as evidenced by low flows through Minden for last several weeks but there was less freshet flow than normal and a very early peak.
* The Upper Gull (that’s us here in AH) is only 70% full
* Kennisis, Hawk and Kushog need water and dams are closed off but operations at Red Pine and Nunakani this week will see those lakes come up;
* The Maple chain (flow through lakes) is very low – and is one example of the inconsistent runoff patterns noted above;

* More folks being up north when they normally wouldn’t be means more eyes and more concerns BUT it’s 6 weeks until May 24th when it’s expected that the whole system will be full
* The forecast seems to be for more normal temperatures and rainfall so fingers crossed for that
* TSW is highly aware, monitoring it all very closely and working hard within some highly unusual constraints
Bottom line:

Lakes are unusually low.
Spring pulled a fast one in terms of historical melts and inflows.
Dams are closed up.
Rain is in the forecast.
There’s 6 weeks until May 24

Flat Creek returns to normal flow into Chandos April 3, 2021

The following is a post to the CLPOA facebook page….

Following up on Iain’s post of April 2, 2021 where he reports that the flow along Flat Creek is into the lake: –It seems as of April 3, the reverse flow has “reversed” and is back to a normal outflow from the lake. On March 25, the lake level was 1026′ 3″. The first log was pulled out of the Paudash dam on that day, with a log being pulled on March 26 and March 28. The Chandos lake level peaked around April 1 just over 1027′, and as of 3 April it is about 1027′ 0″. In 2020 the peak of 1027′ 6″ occurred about April 6. Unless there are some really crazy rains in the next week or so, we have likely passed our peak water for 2021.

In 2021 the ice should go out well ahead of its long term average date of April 18. Last year and this year it will be early, but in 2018 and 19, it was quite late. See graph. If you remember, 2018 and 2019 were high water years with great concerns over flooding.

When the ice goes out late, it seems like the spring melt occurs over a very short time period, thereby giving rise to flooding. Later means a lot more sunshine and warmer daily temperatures, thus turbocharging the melt rate. When the ice goes early, it is a sign the melt has started earlier, and usually at a slower pace, thereby allowing the Crowe to handle the increased flow in a more graceful manner.

The concern with an early melt is if we get a lot of rain, the frost is still in the ground and therefore any rain in the entire watershed becomes runoff, with very little being taken up by the soil. So this amplifies the effect of the rainfall on the lake level.

Chandos is rising!

From March 25 to March 30 Chandos has risen 7″. As reported earlier, water is flowing in from Flat Creek. It is still in reverse mode today, although it was a bit hard to tell as the wind was going straight north, thereby opposing the flow coming south, which created surface wavelets that appeared to be going in the direction of the wind. However, the flowmeter indicated about 0.5 m/sec flow into Chandos.

I confirmed with the CVCA that they had pulled logs from the dam on three days -the 25th, 26th, and the 28th. They believe Paudash has now peaked and they don’t expect to remove any more logs, unless there is a lot of rain.

Environment Canada Gauge Real time Data

Just north of Glen Alda on the Crowe River, Environment Canada operates a Water monitoring Station 02HK005. The results are available in real time on line. Here is a typical graph for the last 15 days:


It is obvious that the flow and level have significantly increased in the last couple of days. The question, which I will attempt to determine, is “has the CVCA taken logs out of the dam at Paudash, or is this totally due to rain and spring melt? ” (suspect both).

The CVCA operate a gauge at the culverts, but I am always wary of the data. The principle of the gauge is to estimate mass flow from the level. However, in a creek that reverses, this type of gauge is inadequate.

Spring Melt 2021

I have started to monitor the flows and levels in our area.

Measuring water level from top of culvert at Flat Creek
Measuring flow with a velocity flow meter at the Flat Creek Culvert

It seems that the melt is occurring later than last year. As of March 25, 2021 the water flow (cubic metres/sec) at the Environment Canada Glen Alda Station is about 8 m3/s, whereas last year about this time it was twice that. This gauge, on the Crowe River, measures the combined mass flow out of Chandos and Paudash.

The ice came out early last year, (April 11) about 8 days ahead of the long term average. This year we have had a lot of rain and some warm weather which no doubt will speed up Ice-Out,

The big question always is what will the spring peak water level be. There are a lot of moving parts, but in general, the more ice/snow that can vacate the water shed early, the longer the freshet will last, and so the lower the ultimate peak level will be.

Ice out Predictions

Every Year Cathy Burgess runs an Ice-Out prediction contest for some kind of prize. I don’t know what it is, or if it’s worth the effort, because I’ve never won. However, if you have a ouija board or a 6th sense foretelling capability, or just want to join the fun, you might want to enter.

Entries must be in by 13 March. You can email her at for details.