The Recommended Boundary follows the Admin. Boundary shared between TRCA and CVC. This decision is justified by the relatively limited additional drainage area identified in the Model Layer along this edge (305 ha, or 1% of the total watershed area), and the fact that TRCA does not manage or regulate areas outside of this boundary.

An additional 43 ha falls between the Admin. Boundary and the Subwatershed Layer along the waterfront, and encompasses areas managed by TRCA (including parts of the Lakeview landform creation project in Mississauga) but not necessarily draining directly to Etobicoke Creek.

The Recommended Boundary follows the Model Layer along all other boundaries and includes the additional 16 ha Lost Creeks Study Drainage. In joining the Model Layer and Lost Creeks Study Drainage, an additional ~2 ha is added to the Recommended Boundary by infilling polygon gaps.