Tenn. Code Ann. § 7-36-123

All moneys of the authority, from whatever source derived, shall be deposited in one (1) or more banks or trust companies and, to the extent required of political subdivisions of this state, such accounts shall be continuously insured by an agency of the federal government or secured by a pledge of direct obligations of the United States or of this state having an aggregate market value, exclusive of accrued interest, at all times at least equal to the balance on deposit in any such account. Such securities shall either be deposited with the authority or held by a trustee or agent satisfactory to the authority. In lieu of any pledge of such securities, the deposits may be secured by a surety bond, which shall be in form, sufficiency, and substance satisfactory to the authority.