D.C. Code § 9-107.53

(a) There is established as a nonlapsing fund, separate and apart from the General Fund of the District of Columbia, the Transportation Infrastructure Improvement Fund. The Chief Financial Officer shall deposit into the Transportation Infrastructure Improvement Fund the GARVEE Revenues and any other funds specifically designated by statute for deposit in the Transportation Infrastructure Improvement Fund. All funds deposited into the Transportation Infrastructure Improvement Fund shall not revert to the unrestricted fund balance of the General Fund of the District of Columbia at the end of a fiscal year, or at any other time, but shall be continually available for the uses and purposes set forth in subsection (b) of this section without regard to fiscal year limitation, subject to authorization by Congress.
(b) The Mayor may pledge and create a security interest in the funds in the Transportation Infrastructure Improvement Fund, or any sub-account or sub-accounts within the Transportation Infrastructure Improvement Fund, for the payment of the Debt Service on the GARVEE Bonds without further action by the Council as permitted by § 1-204.90(f) , such payment to be made in accordance with the provisions of the Financing Documents entered into by the District in connection with the issuance of the GARVEE Bonds.