The Forked Deer River system is the main drainage of the central portion of West Tennessee.

The Forked Deer consists of various streams designated "Forked Deer" and their tributaries. Much of the Forked Deer basin was initially wetlands; however much of this area has been drained and most Forked Deer tributaries have been channelized for agricultural In the mid 20th century much of this was done under the auspices of the Obion-Forked Deer Basin Authority, a Tennessee state agency. Environmental concerns have led to the cessation of channelization on a widespread basis; the federal government's "no net loss" policy regarding wetlands means that further channelization must be offset by creating new wetlands, called "mitigation lands", elsewhere.

Much of the channelized flow is routed into the Obion River just above the mouth of that river into the Mississippi, other streams related to the system have their own mouths into the Mississippi. It should be noted that in some areas where the historic channels are left in place even after the bulk of the flow has been routed into new ones that the historic channels at times still demonstrate considerable flow, especially after heavy rains.