Skating on Cootes Paradise; It’s the next best thing to flying!
By Barb McKean, Head of Education, Royal Botanical Gardens.
If you visualise your favourite places and experiences at RBG, chances are you’re picturing them against a warm and sunny backdrop. Among my own favourite RBG experiences though, is one that only takes place in winter. Sadly, sometimes the season goes by without it being accessible, but like local strawberries, its ephemeral nature makes it all the more anticipated and enjoyable. I’m talking about outdoor skating.
Gliding across Cootes Paradise is pure magic when the entire marsh turns to a sheet of glassy ice. On those special days when the stars align, it’s hundreds of acres of exhilarating and unique skating experience. So why isn’t the ice jam-packed? Despite our hockey culture, the number of Canadian children who can skate is declining: 11% fewer children skate now than a generation ago. Even fewer skate on natural ice, because many adults perceive outdoor skating as a high-risk activity – perhaps another symptom of our society’s disconnect with nature.
People no longer understand how to be safe on open ice – how ice forms, how thick it needs to be to safely bear weight and how it behaves in changing weather. For those who don’t know, here’s a quick primer:
What Makes Perfect Freezing Conditions?
Under ideal cold, calm conditions, lake ice starts as a network of floating crystals that eventually coalesces and thickens into tightly packed vertical columns. Called black ice or blue ice, it is clear, glassy and strong; skating on this ice is sublime (and if you’re being pushed along by a good breeze, it really does feel like flying).
However, into everyone’s life, a little rain (well, snow) must fall. On a body of water the size of Cootes Paradise, a few centimetres of snow adds up to a lot of weight. This strains and depresses the ice and as it deforms under the pressure, cracks (called leads) open up. Water rises through the cracks into the snow’s base to form slush and when the slushy layer freezes, it creates air-filled (therefore less dense) white ice. This flooding/freezing process continues as long as air temperatures are cold enough (though a heavier snowfall will slow or even stop it).
The process becomes a little more complicated when a few other variables enter the picture. In a body of water as shallow as Cootes, ice often freezes onto the bottom. On a sunny day, the sun’s rays travel through the snow and ice and are absorbed by the dark mud on the bottom, causing the lower layer of the ice to melt. This is one reason why areas around the edge of the marsh (even those without a spring seeping from them) are often wet.
Overall, the marsh is shallow but it’s important to remember that water is always flowing under the ice in deeper areas, and the more water flowing, the more complex the ice sitting on it. Currents caused by water flowing from Chedoke, Westdale and Spencer Creeks means riskier (inconsistent) ice in those areas, and the entire area within a 200-metre radius of the Fishway is very dangerous.
Extra caution is needed after warm weather or rain when meltwater/stormwater floods under and over the ice and pushes the entire ice surface around. Leads and pressure ridges form when the ice moves and breaks, often in huge plates that cover dozens of acres. While water flows into the base of the cracks and refreezes the gap if the temperature is cold enough, air pockets may form, and the trace of the crack remains and can catch a skate blade. And once things partially thaw and refreeze, the ice becomes much more difficult to read. The most dangerous time to be on lake ice is towards the end of the season. Even when the ice layer appears thick, it is brittle and not reliable.
Where Can I Get Started?
Treated with respect, the marsh is a great place for winter recreation, and a local winter tradition. Treating the area with respect includes staying off the islands and the shoreline banks along the wetland edge. The dry silty banks erode easily, even in winter. Belted Kingfishers and Bank Swallows tunnel into these slopes to nest each summer, but winter visitors can cause the slopes to collapse.
Natural Lands staff monitor ice thickness, and post information at Princess Point (and at rbg.ca/onthetrails) when the ice reaches a safe depth of 10cm/4”. Heed these signs (and the warnings and out-of-bounds areas noted) while enjoying the ice. Who knows? Maybe you find a whole new reason to fall in love with RBG.