Tennessee Code Title 7. Consolidated Governments and Local Governmental Functions and Entities § 7-51-2802

(a) If a political subdivision of this state determines that an offsite public infrastructure improvement is necessary as part of a development project to service future development, then the political subdivision may require the developer to construct or pay for the construction of such offsite public infrastructure improvements subject to a cost-sharing arrangement between the developer and the political subdivision.  Such cost-sharing arrangement must be based upon the proportionate utilization or impact the development for which approval is sought from the political subdivision has on public infrastructure.

(b) A political subdivision has sixty (60) days from the date on which the approval is requested of the political subdivision by which to make a determination.

(c) The political subdivision's share of the offsite public infrastructure improvement costs may be provided through impact fees collected from other developments, bond proceeds, or unencumbered tax revenues.