D.C. Code § 9-321: Michigan Avenue Viaduct — Use by street railway companies.

No street railway company shall use the viaduct or any approaches thereto authorized by § 9-320 for its tracks until the said company shall have paid to the Collector of Taxes of the District of Columbia a sum equal to one-fourth of the cost of said viaduct and approaches, which sum shall be deposited to the credit of the District of Columbia.