Located on Ordovician bedrock over the Oak Ridges Moraine, the forest attains elevations between 122 and 152 m, increasing westward.

The majority of the area is composed of overburden of ice-contract stratified drift of sand, gravel and silt of varying origin (kame, outwash or collapse).

To address the issue, in 2007 the township passed a bylaw mandating that all concession roads in the forest be closed,[7] and erected fences around the property[8] to eliminate access to ATVs.

The Nature Conservancy of Canada (NCC) has a long-term goal to protect 500 acres (2 km²) of Happy Valley Forest.

[11] In May 2013, NCC announced that 90 acres of conservation lands named Love Mountain in the Happy Valley Forest Natural Area were donated by a family that acquired the land in 1930, and funding for its conservation was obtained from private parties, the Government of Canada, and the Regional Municipality of York.