Singer-songwriter Gordon Lightfoot paid homage to the lake in the song "Couchiching".

The Couchiching Institute on Public Affairs holds its annual conference on the shores of the lake every August.

The Trent-Severn Waterway enters Lake Simcoe by the Talbot River and exits this lake by the Severn River which empties into Georgian Bay.

In a 2012 study, the lake showed a microalgae density of 2.4 × 10^7/cm^2, with a high species diversity.

The lake showed low total phosphorus and high organic carbon content, when compared to Lake Simcoe.