The Mayor of the District of Columbia is authorized to construct grade crossing elimination and other wholly District construction projects or those authorized under § 8 of the Act of June 16, 1936 (49 Stat. 1521), and § 1(b) of the Federal Aid Highway Act of 1938, in accordance with the provisions of such acts. Pursuant to this authority, the Mayor may make payment to contractors and payment for other expenses in connection with the costs of surveys, design, construction, and inspection pending reimbursement to the District of Columbia by the Federal Highway Administration, Department of Transportation, or other parties participating in such projects.