Between 1988 and 1990, the Park Avenue Tunnel was rehabilitated. An amendment to the Metropolitan Transportation Authority (MTA)'s 1982–1986 Capital Program in 1983 provided $46 million in additional funding for the project. As part of the project, structural steel, aged wiring conduits, and the roadbed were replaced, the side walls and waterproofing were repaired and a new drainage system was installed. The contract for the project was awarded in December 1986 and construction on it began in mid-1987, at which point the project's cost reached $105 million. The project was completed in June 1992, ten months after its anticipated completion date of August 1991, resulting from issues with the project design. The tunnel roof's design was changed from being pre-cast to being cast-in-place after wood pilings were discovered in the tunnel, avoiding the need to spend an additional $20 to $30 million. In addition, the concrete ties for the tunnel were defective and were replaced by wood ties, and other costs were underestimated. In the end, the project cost $144 million (equivalent to $ million in ).