Tenn. Code § 69-5-928
If in any year, on account of the delinquent assessments, and the incidental delay in enforcing their collection, the funds are insufficient to pay the bonds and interest, or bonds or interest maturing for payment in that year, the board of directors of the district has the power to borrow the necessary money to make up the deficiency and prevent default, and may make a note or notes, in the name of the drainage district, or drainage and levee district, signed by the board officially. For security, the board may pledge or bind, for the payment of the note or notes, the delinquent, or unpaid assessment, for the particular year. The delinquent assessments, when collected, shall constitute a fund for the payment of the money borrowed. The amount so borrowed by the board of directors shall be paid to the trustee of the county to be used by the trustee as other funds are used in the payment of the bonds and interest maturing.
T.C.A. § 69-5-928