That loud noise you hear echoing from downtown is the trumpet call of New York’s biggest white elephant roaring back to life.

The “temporary” agency that won’t die — the Lower Manhattan Development Corp. — is pushing a new plan for a performing-arts center for the World Trade Center complex, The Wall Street Journal reports.

This one, officials say, will be “slimmed down” to $200 million, far below past budgets of from $400 million to $700 million.

Don’t believe it. Estimates for such projects are always lowballed — just look at what’s happened at the rest of Ground Zero.

But the biggest problem, as we’ve argued from the start, is that the idea makes no sense: The last thing Manhattan needs is another arts venue. It has dozens; new ones keep popping up — and most struggle financially, fighting for every available dollar.

Yes, the feds will contribute $160 million for construction costs — but the center would have to raise hundreds of millions to keep running. And as Michael Kaiser, former Kennedy Center president, told the Journal, “Each time [the project] changes, it’s hard to have faith that the board has a clear vision for what they are trying to create.”

But the LMDC — whose chairman proclaimed the agency’s mission “finished” nearly a decade ago — wants to spend that federal cash, no matter what.

Instead, the LMDC at its next meeting should: 1) Scrap the arts center; and 2) Vote to permanently dissolve itself.