There is authorized to be appropriated to the Secretary of Transportation for capital costs incurred in the planning, design, engineering, and construction of the project authorized by section
76q–1 of this title (including roadway improvements related to the North and South Interchanges and construction of the John F. Kennedy Center Plaza, but not including construction of any buildings on the plaza) a total of $400,000,000 for fiscal years 2003 through 2010. Such sums shall remain available until expended.