The Port Authority has voted to build the World Trade Center Memorial and contribute $150 million toward its infrastructure costs.

Mayor Bloomberg and Governor Pataki last month issued a joint recommendation that responsibility for building the memorial be handed to the Port Authority, which owns the 16-acre former site of the World Trade Center. The recommendation was part of an effort to keep costs under $500 million. Some estimates had the memorial’s cost, including required infrastructure, approaching $1 billion.

The cost of the recently revised plans for building “Reflecting Absence,” designed by Michael Arad and Peter Walker, is $510 million, in addition to about $150 million for infrastructure costs and $80 million for a visitor’s center.

The Lower Manhattan Development Corp., through funds allocated by the federal government, will contribute $250 million to the memorial. The state has committed $80 million for the visitor’s center, and now the Port Authority has authorized additional money for infrastructure costs.

Previously, the task of constructing the memorial belonged to the World Trade Center Memorial Foundation, the non-for-profit corporation created to own and operate the memorial. Yesterday, the foundation launched a national television, radio, print, outdoor, and online advertising campaign to raise the remaining $170 million.

So far, the Foundation has raised about $130 million. Mr. Bloomberg yesterday said he had made a donation to the foundation, but he would not say how much he gave. The Port Authority also pledged an additional $45 million for contingencies, including cost overruns. The Lower Manhattan Development Corp. also will provide an additional $45 million for potential cost overruns.

Construction on the memorial could begin as early as next month, with the goal of opening on September 11, 2009.