After this dry summer little is flowing in east Tennessee. I know little about the large lakes which are impoundments of the Tennessee River, the Cumberland River or the Caney Fork River. I would expect them to have considerable motor traffic.
There are a couple of excellent rivers fairly close to Crossville but whether they will be boatable in October depends on whether there is considerable rain between now and then or not.
Crossville is basically where US Rt 127 crosses I 40. If you drive a short distance north on 127 from Crossville you will come to upper Clear Creek in the Obed/Emory watershed.
Upper Clear Creek is a wonderful Class II overnight trip from Rt 127 down to Barnett Bridge but it requires considerable water. One or two rapids might rate a Class III but they are easily portaged. It is rather too long for a day trip, so it requires leaving a vehicle at the intended takeout and vandalism is always a possibility. It also requires carrying some gear in the boat(s). It is unlikely that upper Clear Creek will be doable this October, but it is worth keeping an eye out on the levels as your trip approaches.
If you drive south along Rt 127 from Crossville you will enter the Sequatchie Valley and come to and drive along the Sequatchie River. Ordinarily some 70 miles or so of the Sequatchie is boatable but this year could be an exception. The Sequatchie is all Class I but a very scenic and pleasant float. It would again require some type of shuttle.
The Middle and/or lower Caney Fork might also be a possibility.
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