Rideau Marina permanently closed several years ago due to a fire. Homestead Land Holdings wanted to build apartments on this site, but (as of 2020) this was tied up in municipal planning objections: https://www.thewhig.com/news/local-news/homestead-drops-appeal-to-rideau-marina-lpat-decision-in-kingston

Unless there's any new news to report, this should either be "brownfield" or deleted. There is no marina on this site.