The Peel River joins the Mackenzie in the Mackenzie Delta. However, a distributary of the Peel is the headwater for a channel that later collects distributaries of the Mackenzie. This means that a channel can be followed for a longer distance downriver until it, itself, disseminates into the shared delta. This arguably adds a greater length to the Peel River.
Steven Kokelj, a specialist in permafrost, has documented significant changes in the balance of dissolved ions in the river's water as the region's permafrost starts to melt.[6]
Ions of elements like calcium and sulphur dissolve easily when the permafrost thaws.