HOUSTON >> Indoor skiing. Amusement park. Water park. Sports memorabilia museum. Riverwalk, though there is only a bayou. And, most recently, a $217 million multipurpose facility.

There has been no shortage of proposals for how to save the Houston Astrodome.

Yet now, nearly 15 years after the last professional sports team left the so-called Eighth Wonder of the World to decay under the relentless Texas sun, voters rejected what some county officials had touted as the only way to save the prized dome from demolition.

A bond referendum would have turned the stadium, once home to MLB’s Houston Astros and the NFL’s Houston Oilers, into a convention and events center. Harris County voted against it, 53 percent to 47 percent.

Still, this might not be the stadium’s last inning.

“There’s a chance,” said Willie Loston, executive director of the Harris County Sports and Convention Corporation, caretaker of the Astrodome and the rest of the vast complex it’s part of, which also includes the Houston Texans’ Reliant Stadium. “The building’s still there. There’s no formal plan or authorization to demolish the building, and until somebody brings such a plan to fruition, there’s a chance.”

A decision is not on the horizon, though. County commissioners are in no rush to approve demolition and waver on other options.

“It’s up in the air,” said Harris County Commissioner Steve Radack. “The proposal was rejected by the voters. We’re back to where we were. Square one.”

The structure was a technological marvel when it opened in 1965, the first domed, air-conditioned stadium. But since 1999, the Astrodome has been a nostalgic symbol of a bygone era. The days when Mickey Mantle hit home runs on AstroTurf, Elvis Presley swooned and crooned and Billie Jean King took on Bobby Riggs in the “Battle of the Sexes” tennis match are faded memories. Even the dome’s most prominent recent residents — Hurricane Katrina evacuees — have been gone for years.

The county still pays some $2.5 million annually to maintain, power and insure the stadium. It’s also paying $8 million to remove asbestos, old ticket booths and exterior walkways. Though the building is structurally sound, the interior is decrepit. Last year, trash littered the aisles between torn, cushioned stadium seats once considered luxurious. A synthetic football field lay in a crumpled, dirty heap.

So what now?

— The Astrodome can remain standing, abandoned but a prominent part of the city’s skyline.

— The county can pay an estimated $78 million for demolition and add another $20 million to fill the gigantic hole left behind, creating an additional parking lot to add to the complex’s current 26,000 parking spaces. Other domes and stadiums have been demolished in recent years, including the Kingdome in Seattle, the old Yankee Stadium in the Bronx and Tiger Stadium in Detroit.

— Or, after demolition, the commissioners could fill the hole with water, creating a detention pond to help with flood control in a low-lying area that abuts a major medical hub.

— The commissioners can again review some of the 21 proposals submitted by the public after the county asked for ideas. Loston said they range from the “sublime to the ridiculous.” This, though, is unlikely because even the more serious proposals had no funding. Some of the others, such as one to collect rain runoff and use it to create indoor ski slopes, or another to transform the arena into a film studio and help Houston become “Hollywood South,” probably would not get the necessary backing.

— They could present a proposal similar to “The New Dome Experience” that was on Tuesday’s ballot, but with either private funding or a combination of public and private dollars.

— A private investor could offer to redevelop the dome, something the county would be open to, Radack said.

“I think we’re all open minded about it,” Radack said.

Some local groups have lobbied to save the dome, and the National Trust for Historic Preservation joined them in a failed campaign to garner support for the ballot measure. A few say they will continue.

Radack, though, notes that despite the media attention, Houston residents don’t seem riled up. Unlike other issues that brought in mail by the bagful — such as the now-abandoned policy of selling shelter dogs for medical research — he has received only two letters regarding the Astrodome.

And only about 13 percent of eligible Harris County voters bothered to cast a ballot.

Maybe, Radack mused, if the Houston Texans had won their game against the Indianapolis Colts on the Sunday before Election Day, the outcome would have been different.

“I think people are mad in general that complex has not produced World Series winners or Super Bowl winners,” Radack said.

But he warned against writing the dome’s obituary.

“I’m open for ideas. I’m open,” he said.