Can the MNRF control major flooding?



It’s being referred to as the perfect storm. A few warm nights, a lot of rain and tons of snow in Algonquin Park has turned the spring of 2019 into a major flood event. In this region alone hundreds of property owners have been impacted by flooding, which coincidentally started in the middle of a public holiday.

The Muskoka River watershed, which flows from Algonquin Park to Georgian Bay with many lakes, rivers, wetlands, and communities in-between, contains 42 water control structures, or dams. Eleven of those structures are owned and operated by the hydro generation sector, one is owned and operated by the District of Muskoka, another is privately owned and operated and the remainder 29 dams are owned and operated by the Ministry of Natural Resources and Forestry (MNRF). So if the MNRF owns the majority of the dams, is it able to control flooding in the Muskoka watershed?

Not according to partnership specialist with the Ministry, Mara Kerry. “None of the dams on the watershed are flood control structures. None of them,” she said. “The dams that we have on the watershed were built quite a while ago, some of them a century ago.”

Kerry said that while the dams have been maintained and upgraded since then, they were built “to keep the lakes high during the summer for industry, for timber, and for boat navigation. So we can manage the levels and flows within a certain range, but if you get extreme weather or extreme precipitation, then you know, in order to stop flooding, you need some kind of a reservoir.”

She used the Red River Floodway in Manitoba as an example. “Think of the floodway they have in Winnipeg. It just diverts all the water away and floods out basically in Winnipeg all these farmers’ fields, so that’s the reservoir. So you would need to shift that water off somewhere else and store it in a big basin, and we don’t have that.”

Kerry likened the lakes in the Muskoka watershed to thousands of bathtubs made up of different shapes and depths located in areas from Algonquin Park to Georgian Bay and the dams operated by the MNRF being the drains. Even with the drains wide open, if the water flowing into the bathtubs is flowing in faster than it’s flowing out of the drains, eventually it’s going to overflow onto your bathroom floor, she noted.

“Every year prior to the freshet we lower the lake level because we know every year it’s going to warm up, the snow’s going to melt and it’s going to rain so we draw the lakes down to the low end of the normal operating zone so that we make room to accommodate the spring freshet. That was done,” she said but noted that the water started flowing quickly this spring, it was accompanied by warm temperatures, and there was a lot of snowpack in Algonquin Park.

Asked how the generation of hydro impacts water levels, Kerry said “they don’t have reservoirs either where they hold back water to be able to generate power in times of low flow. It’s basically a turbine that’s in the river and it’s generating energy when the water’s flowing, and if it isn’t flowing they’re not generating very much energy.”

What about drawing a lake even lower than the operating range spelled out in the  Muskoka River Water Management Plan (MRWMP), especially if a bad year for flooding is anticipated?

It’s a gamble, said Kerry. “You potentially could, but there are consequences to that. So if you, let’s just say, hypothetical situation, you emptied half the lake and then you don’t get any rain and you have a really low year with snowpack or the snowpack melts gradually, then what do you do in the summer? You’ve got a lake that’s half empty… and then you’ve stranded all the fish that live in the lake, all the trout that spawn in the fall…people’s water lines are out high and dry, there’s a lot of implications.”

She said the role of the MNRF through the water management plan is to balance economic, environmental and social interests in the watershed.

“Each of the lakes where there is a dam has what’s called a normal operating zone where we try to maintain levels within this zone, and it’s only when it gets too low that we run into troubles with rocks and people’s waterlines and so on, or when it gets too high. So within the normal range of variation, the water management plan is very effective,” she said. “But it is a balance. And when you have high water or low water, you have to spread that sort of pain out across the watershed,” she added. “We certainly can’t prevent flooding in extreme conditions, but you can manage it within a range.”

As for Huntsville, in particular, Kerry said there are a number of challenges. “There are buildings built on the floodplain that probably should never have been built there, but also there’s the geography of the area. So you’ve got the natural geography sort of pinching all the water coming out of Fairy Lake and [then]further upstream into the [Vernon] narrows. So it can only flow through there so fast, so it backs up. So it’s kind of a product of its location, unfortunately.”

On Tuesday, April 23, Kerry said that all of the dams in the system were open. “Nobody is holding back any water. Everything is running through the system as fast as it can. So what our crews are doing is making sure that there’s no debris blocking the dams, because when you get flows like this you can get people’s docks or trees or picnic tables… if they get caught up in the dams, they can obstruct the flows. So we’re checking them daily for debris, every single dam in the whole watershed and on the Magnetawan, as well as making sure that they’re structurally in good shape.”

What if all the dams and weirs in the system were removed and we simply stopped controlling water flows?

“That’s an interesting question to ask the public, it certainly has implications. What you will get then is a more natural watershed for sure, which has some advantages, but you’ll be prone to extremes—really high water and then really, really low water, and everything in-between.”

Muskoka Lakes Mayor Phil Harding has been particularly critical of the MNRF on social media. He accused the Ministry of not drawing down the system enough, given the amount of snow accumulation in the region.

“Back in March the MNRF admitted they have higher than average snowpack with water content at 171mm. And yet they left Lake Muskoka water levels higher then they did in 2018 (with lower snowpack). Were they anticipating blow (sic) average temperatures and no rain whatsoever from April – July this year? If they anticipated “average” temps – Lake Muskoka should have been drawn down lower than last year,” he posted on his Facebook page on Thursday, April 25.

Harding also questioned why the MRWMP has not been updated since 2006, and taken climate change into account.

John Yakabuski, Minister of Natural Resources and Forestry, in a statement issued on Sunday, April 28, 2019, said that his Ministry has been monitoring the snowpack in Muskoka since last December.

“By February, the Ministry had removed all logs in the south dam to allow maximum flow through the system. In fact, Lake Muskoka was drawn down to one of the lowest levels in recent years to account for the rain and warm weather expected through April,” he noted in the release. “Our government understands the environmental changes facing Muskoka, including increased developmental pressures, severe flooding and weather events. That’s why in August of 2018 we provided $5 million to support the Muskoka Watershed Conservation and Management Initiative, led by the Ministry of Environment, Conservation and Parks, to help us develop a more comprehensive approach to watershed management in Muskoka. We are committed to working with the local community to protect this vital area.”

You can check out the Muskoka River Water Management Plan at this link. You can also go to, developed by the District of Muskoka, to learn more about this area’s watershed.

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  1. Anne Collins on

    In addition to the websites noted, if you wish to have a better understanding of the Muskoka Watershed; it’s values, it’s challenges and what we can do to help, visit the Muskoka Discovery Center’s “Watershed Wonders” Exhibit in Gravenhurst.

  2. Henk Rietveld on

    At last. A government spokesperson telling it the way it is, and not pulling any punches. All we can do is accept the inevitable, and plan for the future. The so-called hundred year flood was based on historical climate events (Hurricane Hazel is still remembered). We’re in a new reality, and need to come to grips with it. Mistakes made have to be acknowledged, and amended where possible/feasible. But, any new development has to recognize the realities, and be strictly controlled for vulnerability to future flooding. Certainly flood mapping needs to be updated. The data bases are there in government maps and surveyors’ notes. They need to be integrated to provide clear “Designated Use Zones”, including, no building below a defined maximum flood line…2019 might provide a guideline.

  3. years ago when I built my cottage and received all the approvals. The Ministry advised me what kind of shoreline to build and what exactly they preferred. I made a mistake listening to them, as I now have 2 expensive repairs since, including this past flood.
    Their own house is not in order yet my house is damaged twice. My next repair will be done in a manner to protect and floodproof my land using common sense. I received bad advice and I should be compensated.

  4. This is a great article giving a reality check on our current ability to manage effects of climate change and land management in our watershed and I appreciated Mara’s descriptions. We need a comprehensive watershed management strategy that looks at how our headwaters, forest and wetland resources (our natural infrastructure) and human infrastructure relate to the water that ends up rushing down our rivers. An update to the MRWMP will only treat the symptoms and only for the short term. Lowering levels even further in the winter will have ecological and social risks. We need to build resiliency into the entire watershed. Anything short of a watershed strategy would be shortsighted and piecemeal.

  5. The Ministry is misleading the public. “It’s a gamble, said Kerry. “You potentially could, but there are consequences to that. So if you, let’s just say, hypothetical situation, you emptied half the lake and then you don’t get any rain and you have a really low year with snowpack or the snowpack melts gradually, then what do you do in the summer? You’ve got a lake that’s half empty… and then you’ve stranded all the fish that live in the lake, all the trout that spawn in the fall…people’s water lines are out high and dry, there’s a lot of implications.”

    They know EXACTLY how large the snowpack is. They can calculate the size of the freshet very accurately. the only variable is the amount of rain, and that is predictable. Any agency with any forethought would have run down the lakes to record lows in late Feb early March in anticipation of the coming flood. Frankly the mismanagement of the water table is a risk to taxpayers as the Ministry should be sued for it’s management of the water levels. If this management was returned to locals the flooding risk would be greatly lowered. Queens Park is NOT the place to manage the Muskoka watershed.

  6. David Sculati, Bala on

    This is the best article on the flooding aspect of the watershed that I have seen. Another good read is the article in the current (May 2019) issue of Unique Muskoka magazine entitled “Understanding Muskoka’s Watershed” by Dawn Huddlestone.

    I think that it is counterproductive for politicians to take public pot shots at the MNRF. As the article points out, they are working as best they can with a system that was never designed for primary flood control. What we do need is constructive criticism as well as better guidance for any construction along our watershed. We could also benefit from suggestions on what tweaks could be made to the system that might be helpful.

    As an example in my area, the Moon River is the major drain from Lake Muskoka. However, before the flowing water can reach the next structure in the system, (Ragged Rapids dam), it has to pass through narrow chutes originally blasted out to move logs through the system. During flood events, the water level below the chutes is actually below normal levels because the chutes act as a choke point. Perhaps the chutes choke point could be modified to allow more water to pass through more quickly reducing water levels on the main part of the river.

  7. And Premier Ford’s initial budget cut the funding of Conservation Authorities by 50%; in the face of the Timmins Flood Plus: Why are we attempting to shift the blame to the MNRF, whose budget was also drastically reduced? These catastrophic events are occasioned by climate change; they require study in each sub-watershed; land must be purchased (If provincially-owned land is not satisfactory); reservoirs must be excavated (and the retained water bled back into the system, after the spring freshet is over).
    Each reservoir functions as a stormwater management pond; such as are required for developments with large expanses of asphalt. Frozen/saturated ground is impermeable; similar to asphalt. Unfortunately, in Muskoka, it is highly possible that blasting would be required to construct these ponds. The personnel, who could have located less expensive alternatives in the field, have been let go; leaving the remaining engineers/technologists to proceed on a “best guess basis” from topographical maps.
    Never let a multi-millionaire set a budget. Filling a few sandbags is probably the only practical action he’s taken in years.

  8. It would be really, really useful to update all those dams, so that their function can include not just retention but release. A good scheme with work for locals and results for this century, not the last one.

    Our forefathers were wise enough to build ’em. Are we wise enough to adapt?

  9. Brian Tapley on

    In Lake of Bays case this year they lowered it as low or lower than I’ve ever seen it. This is not a huge amount of course, being less than 4 feet lower than “normal but that is due to many features, not least of which is that the control dam in Baysville does not have the ability to go much lower than about 5 feet, or so I am led to believe. I think this may be correct because the dam itself ceases to be the controlling factor when you get down near the lower limits and the channel leading to the dam does become the controlling item so you could possibly completely remove the Baysville dam and not end up with significantly lower water levels than they achieve this spring.

    The other item, that was touched upon is that of water intakes. I have 4 that supply my various buildings. The shoreline where I am located is shallow so most of these reach out over 200 feet into the lake. If the spring water level was to drop significantly more than it did this year, then with normal ice cover I would experience problems with water supply. Of course I could build changes to my systems to accommodate such a drop, but it would take time and money and to consider this I’d need to know how far and how often the powers that control the water level would plan to go in this direction. Nobody talks about this so far.
    Not everyone has the funds to just drill another well like our local township can do and even then, in the case of the Dwight office the water is not fit to drink and they need to rely on bottled water. One would not think this with the largest wetland in the immediate area just across the highway but such is the way with wells. What you see on the surface is often now what you get when you drill.

    On the bright side, generally Muskoka is blessed with an abundance of good clean water and very rarely, for a few weeks, a bit too much. There are an awful lot of places who would trade places with us in a flash as they simply don’t have the water at all! Maybe we complain too much?

    • sylvia purdon on

      Thank you for this rational explanation of your waters. I fear not all the discussions will be so well thought out and based on reality.

  10. I am shocked that the municipalities still allow filling in wetlands; holding areas, water purification zones. Look at all the wetlands filled in around Port Carling.

  11. Bill Beatty on

    The answer to the question is no.Triple the MNR budget wouldn’t have prevented the massive damage that took place…The blame game after the fact is pointless…We have altered the Terrain and now it alters us !

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