The Goose in question is not a snow goose. It is a domestic goose. It appears to have leucistic (washed out) traits. It primaries are grayish brown and not black as in Snow Geese, The neck has black striping where there should not be any.
Also from the pictures it appears to be foraging for bread/corn handouts. Wild Snows avoid people. Especially this time of year.
The thing about Lasalle marina park is that it attracts and holds exotic waterfowl all year long. The late winter tend to be the best time. Here my list of exotics seen at Lasalle marina over the last 10 years, Whooper Swan, Chloe Wigeon, bar-headed geese(multiple), egyptian goose, barnacle goose, Greylag goose, Chinese Goose, and several strains of domestic Mallards ranging from slightly different to big, white, and fat. I never know what exotic I will see that has arrived for the easy meals that are put out several times daily.
Also domestic goose/canada goose hybrids are regularly found along the Lake Ontario waterfront. And they come in a widerange of shape, sizes and plummage.
As for current exotics Keep an eye out for a Black Swan it has been roaming the lakeshore in Durham region for several months now.
Cheers
Tyler