It is fed by Bonanza Creek and drained by the Slocan River.

In 1947, a Canadian Pacific locomotive was lost in the lake when a barge on which it was being carried sank.

The largest community on the lake is a village known as Slocan City.

In addition to Slocan City (officially now a "village", but usually referred to locally by its old name of Slocan City to distinguish it from Slocan Park and South Slocan), other towns and communities on the lake include the twin communities of New Denver and Silverton, midway up the lake's eastern shore, Rosebery slightly north of them at the mouth of Wilson Creek, and Hills at the lake's north end.

The Canadian Pacific rail line from Nakusp via Bonanza Pass now dead-ends at Rosebery Slip, on Slocan Lake, but originally ran into Sandon.