It has to be mindful of our climate and man-made beaches require a lot of science to maintain quality and viability. It's more than just dumping a bunch of sand.
You're talking an expansive beach. I'm talking something very small, and there's already some inlets from the lake into coves. I know, because when I walk the Big Black Lab across the waterfront, Ont Place is the only place I can find to allow him to dip into the water to get soaked. It's not drinking water dogs need to deal with the heat so much, it's getting soaked to stay cool. Cherry Beach dog park takes next to no upkeep, and it's sand on fill. There are no ponds or pools for dogs in the core that I'm aware of. It's Toronto, and too abstract a concept for here.
But beyond making that point, it appears that beaches already exist....or did. The West Island is mostly inaccessible right now, but looks like it hosts an extensive one, and as per "Echo Beach" no-one I've talked to down there seems to be aware of its existence. What I was doing (although the Lab is now aging, he's nine and half and it's unwise to walk him more than 10 kms or so even soaked) was literally walking from the east end of the city to the west along the waterfront trying to stick to the water's edge...very difficult especially in the core section. We'd enter from the 'East Entrance' get him soaked from where the grass merges into the water almost dead centre of the map, and then exit across the most western bridge. From there to Sunnyside, there's no other place to wet a dog, let alone a kid.(Edit: In the Lake) It's concrete barrier across the Waterfront. How absolutely absurd for a "world class city" hosting an agency specifically called "Waterfront Toronto".
Lots of facilities for yachts though...
And now I Google, I realize why I'd missed the "beach":
Toronto Echo Beach
Outdoor medium sized venue at Ontario Place, downtown Toronto, Canada
Venue is next to and managed by the Toronto Molson Amphitheatre - Live Nation
Venue websites:
http://www.ontarioplace.com/echo-beach
http://www.livenation.com/venues/14914/td-echo-beach
But look here!
https://www.google.ca/maps/place/To...23555502ab4c477!8m2!3d43.653226!4d-79.3831843
Wouldn't you know it? Closed off to the public...I always wondered what's behind that gate on the path/road and the chain-link fence keeping out mere mortal taxpayers.
Great place for a gambling casino...and a ferris wheel. Maybe a monorail? And more berths for the filthy rich to park their yachts...
Post Edit: It's a safe assumption that there's more dogs than children in the lower central core of the City, and there are some fairly good dog parks, but none with wading or swimming pools for dogs to get soaked in. Toronto has catered well to splash pads for kids for generations, but dogs are not allowed in them (for understandable reasons) and I can accept the reluctance to provide dog dips in the past, but with so many condo dwellers with dogs, it's well past time to start. And providing access to the Lake, even in a modest way, makes more sense than fixed splash pads for dogs in terms of the water circulating.
Just as we need to provide amenities for humans to stay healthy and exercise, so it is with dogs. And as average temperatures continue to rise, that's not an amenity. It's a necessity. Healthy dogs inspire healthy people, and vice versa.