Harrison Lake is much longer than it appears when you look at it from Harrison Hot Springs, at 60 kilometers long it covers over 200 square kilometers. While it is now a freshwater lake thousands of years ago it was not a lake at all, but an arm of the sea. It varies in depth from just a few feet to a maximum depth of 279 m. (916 ft.). It supports a rich bio-diversity of both seasonal and permanent animal species including: Cutthroat trout, Rainbow trout, Dolly Varden, Pink, Chum, Coho, Sockeye, and Chinook Salmon, Sturgeon, Harbor Seals, Canadian Geese, Herons, and too many different types of water fowl to list.
A word of warning: it is a large, 60 kilometer long, glacier fed lake and the water can be very cold. As well, storms can make the lake a dangerous place to be, so exercise caution and common sense.
The view from the lakefront is dominated by Breckenridge Glacier in the distance and by Echo Island, so called because there is a sensational echo on its western flank. The south end of the lake is very shallow, almost out to the island. Beyond that, the depth drops off to more than 900 feet.
For a great short video of a drive up the east side of Harrison Lake check out this Youtube video.