Renovation work is going on at Nassau Coliseum in Uniondale...

Renovation work is going on at Nassau Coliseum in Uniondale on Tuesday, Jan. 10, 2017. Coliseum developers have shelved plans to have a minor league hockey team play home games at the renovated arena when it reopens in April, despite agreeing to do so in their contract. Credit: Newsday / J. Conrad Williams Jr.

Nassau County Executive Edward Mangano is counting on a power-play goal. Big time.

He’s putting aside some terms of a lease that should provide significant revenue to the county in exchange for the unlikely possibility that the New York Islanders will return to Nassau Coliseum.

When Mangano and developer Bruce Ratner first announced their deal to redevelop the arena and the surrounding area in 2013, they highlighted promises of a minor-league hockey team, a few regular and preseason Islanders games, as well as retail shops and restaurants guaranteed to be finished just a few months after the arena was completed.

For now, although the arena is scheduled to reopen in April, none of the other promises will be a reality. The county is choosing not to enforce several clauses in its lease with Nassau Events Center, the group led by Ratner and Brooklyn Nets owner Mikhail Prokhorov that’s developing the Coliseum and the area around it. That’s a risky move.

The way Mangano sees it, it’s not county money he’s risking; the county will still earn the minimum rent of $4 million a year. He is counting on the idea that the Coliseum can thrive without an anchor tenant. The arena will be reopening without one, although the lease requires a deal with an American Hockey League team. (The Long Island Nets, an NBA Development League basketball team, isn’t enough of a draw to make money and fill dates.) And the arena will open without a deal to have the Islanders play games there, again contrary to lease terms, although there’s a payment Ratner can make instead.

What’s more, Mangano is allowing a delay in construction of attractions on the arena plaza, such as a movie theater and an indoor skydiving facility, despite an agreement that they be completed just after the arena. Now, he’s thinking of adding housing. Hempstead Town zoning allows for up to 500 units. A lawsuit between Ratner and Blumenfeld Development Group regarding who has control over the plaza’s development is complicating matters, despite public promises from Ratner and Blumenfeld representatives that it wouldn’t affect the plans.

It’s troubling that a county legislature-approved document, which the county, legislature, and taxpayers relied upon when Nassau Events Center was chosen, means so little now. An attorney for Nassau County says the lease allows Mangano to make changes without legislative approval. However, it would have been appropriate for Mangano to discuss the changes he was considering far earlier. The minor-league team deal, for instance, was supposed to be done more than a year ago, before it became clear the Islanders were unhappy in Brooklyn and looking for a potential new home. But little was said about it until now.

Economists and other experts say a suburban arena without an anchor tenant would have trouble surviving. Mangano and Nassau Events Center officials insist that concerts already scheduled show the arena will be a financial success. Taxpayers need more concrete information to be assured the Hub will be an economic center, and not the site of a waiting game. Perhaps Mangano knows something more, and has a definitive plan to make the Islanders the arena’s anchor and to add new development. But if not, the county can’t just rely on hopes and dreams. — The editorial board