BELLE GLADE, Fla.--Beyond the brown grass of South Florida's cities and subdivisions, beyond the tattling over illegal sprinkling, residents of the tiny towns rimming Lake Okeechobee are worrying about their livelihoods, not their lawns.

Through a combination of management and Mother Nature, the lake has sunk close to its record low this winter, with little rain in the long-term forecast.

And while Okeechobee is Miami-Dade and Broward counties' backup -- feeding water into canals that bolster South Florida's storage areas -- its receding level is crippling the local farming and fishing industries whose fortunes are intertwined with the health of the lake.

."It's like an insurance policy for Miami," said Tom MacVicar, former deputy director of the South Florida Water Management District, "but it's the economy for those areas."

Throughout its evolution from unbound lake to regulated reservoir and fishing paradise, Okeechobee has blessed and cursed the people of towns at the southern foot of the towering levee built 70 years ago to tame the lake.

In the 1920s, hurricanes blasted lake water through what then was a small muck dike, killing thousands of people. Farmland runoff has been steadily polluting the lake for decades, tainting the direct water supply for some lakeside towns and driving away wildlife. And this year, significant rainfall is not expected until summer.

"It's like a wild horse that's been broken," MacVicar said. "You can put a saddle on it and ride it, but that doesn't mean it won't kick you once in a while."

At Slim's Fish Camp in Belle Glade, the ramp from land to the floating dock was level a year ago. Now it descends eight feet from land to water.

"It's going to get worse before it gets better," said Gordon Corbin, co-owner of Slim's. "It's been a slow season. We're not doing near what we should be doing."

Fewer people are coming out to fish. Some cannot even get their boats into the lake without running aground, much less troll their favorite fishing spots.

"Everywhere I fished last year is about a mile from the water now," said William Fletcher, a professional fisherman from Memphis who was in town recently for a tournament in the legendary bass breeding grasses.

At 730 square miles, Okeechobee touches five counties. The only way to see all of it at once is to fly high above it. From the surface of the lake, the horizon can range from a stunning sunset to an endless bed of lilies to a line of leafless skeletons of melaleuca trees --non-native invaders the district is systematically killing because they crowd out natural plants.

Fishing and boating at Okeechobee bring in close to $100 million to the state economy, although that figure may be lower this season and possibly in the future if regulars, wary from this year, do not return.

At Roland Martin's Marina in Clewiston, revenue is down 30 percent compared to last year, even with hundreds of professional fishermen arriving regularly for tournaments.

Next door at Anglers Marina, nearly one-fourth of the boat slips are too shallow for a boat to dock.

Tables sit empty at the grand Clewiston Inn, a white-columned shrine to Big Sugar listed on the National Register of Historic Places. "Our dining-room business from the marinas is down quite a bit," Manager Chris Hill said.

The water management district has dramatically restricted the amount of water that sugar and citrus growers can use. "Not being able to water your lawn or wash your car except for two days a week is quite a different restriction than not being able to water your crops," said Judy Sanchez, spokeswoman for U.S. Sugar, based in Clewiston and one of the Big Sugar companies that, collectively, own more than 420,000 acres in the area.

But as crucial as are Okeechobee and the economies of the towns around it, they may not be on the maps of many South Floridians, whose geographical grasp of the region rarely goes west of Florida's Turnpike. "You mention Lake Okeechobee and they say, `What state's that in?' " said Corbin, the owner of Slim's Fish Camp.

Dr. Alan Steinman, director of the water management district's Lake Okeechobee program, said the massive levee, while essential to making the lake a manageable resource, also prohibits the sort of relationship many people in South Florida expect to have with the water. "Whether you're in Boynton Beach or Miami Beach, there's a certain disconnect from the lake," Steinman said. "The fact that there's a levee around it and you don't see it every day -- you don't have that visceral connection with it."

Things are different for those at its edge. "They may not fish on it, but they draw their water from it. And if that water stinks, then it's a drag," Steinman said. The drought currently vexing Florida is only one reason the lake is so low.

Last spring, the district took the controversial step of lowering the lake by a foot, responding to concerns that consistently high water levels -- more than 15 feet above sea level -- were killing underwater plant life crucial to the lake's long-term health and to fish populations. Some say the move backfired. Rainfall has been lighter than expected, and the lake has sunk below 11 feet and could go below nine feet, even as plants and wildlife around the lake seem revived.

The dire situation was dramatized last week when thousands of acres of lake bottom burned and smoke filled the sky like a summer storm. But lake experts said the fire likely helped the lake by clearing out melaleuca and other non-natives, allowing desirable plants to reestablish themselves. While farmers and some in the fishing business may grumble, some say they see another bright side to their current troubles, including expectations for increases in fish spawning in flourishing grass beds.

"It's had a devastating effect on the economy around the lake, but I will say this: We have been needing this for years, the low water," said Mary Ann Martin, who owns Roland Martin's Marina. "If it's going to get low, let's just take it all the way down."

That kind of extreme action could devastate the big cities to the south, which depend on the lake most at the driest part of the dry season, just before summer rains replenish the local aquifers that Broward and Miami-Dade rely on throughout the year. This year, for the first time, the district has installed pumps that can force water down the concrete canals to the urban counties if necessary. In the past, the lake has been high enough that simply opening the fortress-like locks would send water south.

The journey to Okeechobee is 90 miles long and a century old, beginning in earnest with a brazen agricultural magnate, Hamilton Disston, who helped reroute the headwaters of the Everglades and convert the soggy swamps south of Okeechobee to farmland. While Okeechobee has defied settlers since they first tried to collar it, South Florida has always relied on the looming levee as much as the water behind it. Follow the canals Disston first dug: north from the cities, west of the terra-cotta rooftops, through the sugar cane to the crest of a 35-foot man-made levee -- the Herbert Hoover Dike -- which was built in the 1930s to prevent the lake from flooding towns and fields when waters rise. The decade before, hurricanes in 1926 and 1928 killed close to 2,500 people when water broke through an early levee of piled muck at the south end of Okeechobee.

"They didn't need the dike every year, but they sure needed it when they needed it, "MacVicar said. "Those communities would not exist without the dike."