FORT LAUDERDALE, Fla. – With inviting beaches that run for miles along South Florida’s shores, it is easy to put sand into the same category as turbo air-conditioning and a decent mojito – something ever present and easily taken for granted.

As it turns out, though, sand is not forever. Constant erosion from storms and tides and a rising sea level continue to swallow up chunks of beach along Florida’s Atlantic coastline. Communities have spent the last few decades replenishing their beaches with dredged-up sand.

But in South Florida – Miami-Dade, Broward and Palm Beach counties – concerns over erosion and the quest for sand are particularly urgent for one reason: there is almost no sand left offshore to replenish the beaches.

In these communities, sand is far from disposable; it is a precious commodity. So precious, in fact, that it has set off skirmishes among counties and has unleashed an intense hunt for more offshore sand by federal, state and local officials who are already fretting over the next big storm. No idea is too far-fetched in this quest, not even a proposal to grind down recycled glass and transform it into beach sand. The once-shelved idea is now being reconsidered by Broward County.

The situation is so dire that two counties to the north – St. Lucie and Martin – are being asked to donate their own offshore sand in the spirit of neighborliness.

"You have counties starting wars with each other over sand," said Kristin Jacobs, the Broward County mayor, who has embraced the recycled glass idea as a possible stopgap. "Everybody feels like these other counties are going to steal their sand."

St. Lucie and Martin counties are none too keen to sacrifice their sand for the pleasures of South Florida. The last time the idea was mentioned, in 2006, it engendered accusations of subterfuge and raised so much ire that it was dropped.

If a recent spate of public meetings on the issue held by the Army Corps of Engineers is any measure, little has changed, despite a new study by the corps that says the two counties have enough offshore sand for at least 50 years.

"What happens in 50 years when all that sand is gone?" asked Frannie Hutchinson, a St. Lucie County commissioner. "Where are we supposed to go then? I told them to take their sand shovels and sand buckets and go home and come up with a better plan."

In a state where the lure of pristine beaches is pivotal to a robust economy, hoarding sand is not unlike stocking the basement with toilet paper, water and peanut butter. One never knows when the next storm could sweep away a beach and wreak havoc on beach communities.

"When we got hit with back-to-back hurricanes, we had no beach in front of our infrastructures: A1A was wiped out," Hutchinson said, referring to storms that engulfed a busy beachfront road.

The reason for all this agitation is straightforward: Miami-Dade County is officially out of offshore sand, which is environmentally sound and easily accessible. The last piles will be depleted in February, when sand replenishment is completed on the beach of the affluent village of Bal Harbour.

Broward County is not much better off; its offshore sand is nearly depleted. And Palm Beach County’s stocks are dwindling rapidly.

The reasons for the disappearing supply of sand are various. For one, these counties have been refurbishing their beaches for decades. The problem has also been worsened by sea-level rise and the number of jetties, or cuts to build seaports, that have proliferated, which causes sand to pile up on one side of the jetty but not the other.

The scarcity of sand is also a function of geography. There are three reef tracks running alongside Miami-Dade and Broward, which make dredging difficult. And the continental shelf narrows greatly here, meaning that the ocean gets too deep too quickly.

So while erosion is a problem along all beaches on the Eastern Seaboard, other counties and states to the north have large areas of ocean they can use to dredge sand. In South Florida, the slice is relatively minuscule.

"We are just limited in the actual amount of sand that’s available to us," said Stephen Blair, who is in charge of beach restoration for Miami-Dade. "They have a much bigger area in which to look for sand."

In South Florida, offshore sand has been essential in bolstering constantly eroding beaches, and healthy beaches are vital to tourism. Guests who routinely pay $400 a night for a Miami Beach hotel room come with expectations. One of them is sand to frolic on.

"They are not inclined to come if there are no beaches to lay on," said Jason Harrah, the Army Corps project manager overseeing Miami-Dade beach restoration.

Broward County faces the same problem. "There is pressure from everybody – governments, the chambers of commerce," said Eric Myers, who is in charge of Broward County beach restoration.

Beaches also safeguard the health of the high-priced cities and towns that abut them. Wide beaches, preferably with dunes and vegetation, protect buildings and roads by serving as buffers to waves churned up by large storms.

"These beaches, people think they are recreational, but they are storm damage reduction," Harrah said. "They are meant to sacrifice themselves for the loss of property or life. In the event we have that kind of storm, we wouldn’t have the means to replenish them."

Offshore sand has always been the first choice to counter beach erosion. It is inexpensive and does not disrupt reefs or marine life. This is why the Army Corps and the state are hoping that Martin and St. Lucie counties will come around and free up some of their sand, which could then be dredged and shipped farther south.

The only other option at the moment is buying sand from mines in Central Florida and trucking it in, which is what Broward County is doing for a stretch of its beaches. Doing so is more expensive, reserved for low-volume projects, logistically difficult and largely disliked.

"There would be 20,000 trucks going through South Beach in tourist season, so you can imagine that," Harrah said.

A third option is buying sand from countries in the Caribbean, possibly the Bahamas. Under U.S. law, the Army Corps must show that domestic sand is not available for economic or environmental reasons before it can use foreign sand.

Broward County is exploring the cost of recycling glass to fill small gaps in its beaches – it is more costly than offshore sand, but it is not yet clear by how much. Broward would also have to find a nearby facility to process the glass and must complete the final phase of its environmental study. Other states have used recycled glass before, but mostly for small projects like golf courses.

For now, the idea remains on the table. It is creative, said Jacobs, the Broward County mayor. It could promote a market for glass, she added.

The county is now looking to finance the last part of its environmental study, and will then weigh the costs. The sand has so far proved an excellent mimic of regular sand, which comes from glass, after all. "If we could generate our own sand," Jacobs said, "it would be fantastic."

© 2013 The New York Times Company