UPDATED LOW WATER LEVEL ADVISORY
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Further to the CEWF alert of August 19th, the latest TSW 2-week drawdown forecast puts our lakes at 2 to 4 weeks ahead of a 'normal' year, with the drawdown continuing.
This means we are currently experiencing water levels similar to what we would usually see in mid to late September.
Shallow passages, docks, and boat ramp usage/access could be affected. Depending on your individual circumstances you may want to take action much earlier than usual. Such actions may include taking your boat out early or checking your foot valve for appropriate clearance.
This suggestion is particularly important for seasonal folks who may not be at their properties between Labour Day and Thanksgiving.
The TSW drawdown forecast can certainly change with significant rainfall over large areas however, recent localized rainfall is unlikely to make any discernible change in the current levels situation.
The reasons for the unusual drawdown include no significant rain all summer and accelerated evaporation from high temperatures in addition to the maintenance of minimum flows for downstream water requirements such as agriculture and the proper management of drinking water and effluent systems.
CEWF appreciates the many enquiries received of late. We’ve assembled the most common enquiries in the 9-point FAQ below.
We will continue to monitor conditions and keep you informed as necessary. The most up to date information is on our website at www.cewf.ca where you can also subscribe to get our e-alerts. We also respond to emailed questions at cewfca@gmail.com
FAQ
1. Where the heck is my water?!
Your lake is part of the Trent River basin. The Trent River basin encompasses some 218 lakes in the Haliburton Highlands region, 35 of which are "reservoir lakes" that are directly controlled by Waterway dams. These 35 lakes have been "reservoir lakes" since 1905 when our communities and needs were very different than they are now.
Water from the reservoir lakes flows south via a number of river systems, into the lake system in the Kawartha Lakes region and ultimately, into Lake Ontario at Trenton. The Trent River basin drains more than 12,000 km² of land in Central Ontario!
En route to Lake Ontario, our water supports several downstream uses including agriculture, drinking water systems and sewage systems for larger communities. Our water also travels through the Trent-Severn Waterway, a National Historic Site involving a 386km waterway that was first opened in 1922 to connect Lake Ontario and Georgian Bay.
The dams that control the levels in our reservoir lakes are operated by the Trent Severn Waterway (TSW), which is a department of Parks Canada. Managing the reservoir system's dams is a complex job, and CEWF works directly with TSW to ensure the needs of the reservoir lakes are an ongoing part of TSW’s decision making.
This summer's unusual weather has affected the lakes more dramatically than it has in a long time. The last time the water was this low in August was 2012, when there were widespread issues with foot valves, boats, and access points.
To see the map of how our water gets to Lake Ontario, go here.
To learn more about the Trent Severn Waterway National Historic Site, go here.
- They take our water for boating on the Trent Severn Canal
Not quite. The TSW does, indeed, take water to maintain flow levels that support the pleasure-boating needs of the Trent Canal however, our water is also used to support agricultural needs, and community drinking and sewage systems along the way e.g. the Peterborough and Trenton water systems.
Importantly, the minimum flow of water required to properly operate the Peterborough drinking and sewage system is the same flow of water required to safely operate the Trent Canal.
So, while our water does get used to support pleasure boating in the Canal, there are other important considerations for the water along the way, and our lakes are not drawn down only for boaters on the Canal.
- TSW could keep our water here, they just don't want to
Not true. TSW manages the entire system through what's called "integrated watershed management". This means that the requirements for water throughout the entire system are considered in water management decisions.
There are priorities for water, as noted above; and in drought situations like we have now, all demands for water are reduced to minimum levels.
How much a lake is drawn down is calculated on the storage depth that’s available in a lake. Storage depth is typically based on the dam configuration at the outlet, in particular, the number of stoplogs. And while lakes are different in terms of storage depth, the integrated management model calls for lakes to be drawn down “equitably”; that is, they are reduced by as similar a percentage as possible.
For example, if all lakes are being drawn to 50% full, 1 metre of storage depth on Lake A means a 0.5 metre drawdown, but if Lake B has 3 metres of storage depth, it will have a 1.5 metre drawdown. So, while the percentage drawdown is equitable across all lakes, it may not feel like the results are.
Before equal percent drawdown was introduced, lakes were more or less drained from top to bottom, like a series of bathtubs. If your lake was at the top of the watershed (the Hawk Lakes), your lake lost upwards of 11' of water before Halls Lake saw too much of a difference – and so on down the system. That sure wasn't popular!
The history of public objection to older water management models is long and storied. It's the good work over many years of lake associations, citizen scientists and organized groups that have resulted in the fairer integrated management model.
However, extraordinary weather like we've had this year makes the TSW's complex job more complicated. If there's any so-called good news, it's that the equal percent drawdown means every lake is feeling the pain to some extent ...
Please know that CEWF is in touch with TSW several times a week to receive and share important information about the reservoir system, which we pass along to the public.
- Why am I paying waterfront taxes if my water is going to vanish?
We hear you - we're all waterfront property owners, too!
We pay property taxes to our municipalities for the services they provide which, unfortunately, has nothing to do with Parks Canada and the 120-year-old reservoir system.
On the upside, CEWF works hard to maintain its direct working relationship with the TSW on your behalf. And we’re the only organization that does so. In fact, when we send out information releases, the municipalities within the Trent River basin are part of our distribution list.
Many elected officials are subscribers to our e-alerts so that they can stay abreast of what CEWF is working on. Our e-alerts are ONLY about water levels and flows. You can subscribe too. Go here.
- How do I know how much my lake will go down?
The TSW manages a terrific interactive map where the levels at each dam are posted daily. The easiest way to see your levels is to look at the graph of the gauge associated with your lake. To see that, go here , click on the map with all the blue pins and scroll around for your lake.
To dig a little deeper on understanding the graphs and charts, CEWF has provided a short How To. It may take a bit to get your head around it, but once you do, it's easy-peasy. After that, receiving our e-alerts via subscription means the latest info pops into your Inbox and you'll be in the know sooner than most.
To see the How To, go here.
- The TSW mandate is very outdated!
The mandate of the TSW, as per the Federal Government, is:
- Mitigate flooding/protect infrastructure/public safety (this means operate the dams well)
- Manage municipal drinking and agricultural water supplies
- Provide for navigation in the Trent Severn Waterway ("the Canal")
- Protect natural environments
- Optimize recreation (eg. docks, boats, tourism)
- Optimize waterpower generation
Modifying this mandate - and lobbying the federal government to do so, has been exhaustively discussed by many groups for decades. It's simply not a priority for the federal government and for now, the CEWF's preference is to work WITHIN the relationships it's built with the TSW in order to continue to share important information with the public.
- Who is the CEWF and what do you do?
The CEWF is a group of citizens who are watching the water for you. We have a strong, working relationship directly with the TSW decision-makers.
Our Executive Committee members are engineers, scientists and university professors - with a landscaper and a historian thrown in for good measure. Each is a waterfront property owner within the system. We meet monthly, year-round, to discuss a range of issues related to our water levels and flows – even in winter!
CEWF's membership comprises 32 lake associations across the Trent River basin but because not all lakes or people belong to lake associations, the CEWF represents the interests of an estimated 30,000 waterfront property owners - even if they don't know we're doing it!
See more about who we are and what we do here
- I've heard people talk about flow through lakes, what are those?
A "flow through lake" is one that doesn't have a dam controlling it. In the Haliburton region, each of Cranberry, Pine Green, Maple and Beech lakes are flow through lakes. This series of lakes is referred to as "the Maple chain". The closest dams for these lakes are at Eagle Lake and Twelve Mile.
Together, the reservoir and flow though lakes are often referred to as "the RaFT lakes".
To see where the dams are, go to this map.
- This year was weird, I’d like to learn more
The CEWF annual communications meeting is taking place Saturday, September 6, 2025. You can attend in person or via Zoom.
In person: 10am at the Highland Hills United Church in Minden
Via Zoom: please get the link from your lake association or by emailing cewfca@gmail.com