GREENVILLE, Miss. — Stephanie Park, 70, waited with the body of her neighbor for two hours before the Washington County coroner could make it to his house here in the Mississippi Delta. Rigor mortis had set in.

About 15 miles to the southwest, Lori Gower, 57, had to drive her Dodge Charger through a nearby farm field swamped by heavy rain to get to her house after work. The car’s engine flooded and her husband, Mack, 64, had to tow her out. Mack, for his part, couldn’t get his diabetes medication delivered.

Just 50 miles north, Rives Neblett, 75, a Delta farmer, has watched the production cost for each bushel of soybeans increase by more than seven cents because his harvest truck has to take circuitous routes.

The source of all four Mississippians’ troubles: Bridges that were closed. And not temporarily closed because of accidents or flooding, but closed because of old age, splintered supports, or cracked concrete.

Mississippi, a relatively poor state, has never been known for its gleaming transportation network, but the situation today is worse than ever. Across the state, residents now have to circumvent nearly 500 closed bridges that have been declared unsafe, according to the Mississippi Office of State Aid Road Construction. Another 1,742 are posted with specific weight limits because of structural deficiencies. Combined, that accounts for more than 20 percent of the county and local bridges in the state.

While the bridges have closed, more money to address their inadequacies has not been made available, because increasing taxes is a non-starter for the Republican-controlled state government.

Without a solution, county workers tear up the asphalt just ahead of the bridges here and put up florescent orange signs to warn oncoming drivers that the crossing is out. The new roadblocks force many people throughout this state to drive dozens of miles out of the way to get to work or even drive their car through the flood-prone dirt at the edge of a farmer’s planted field.

In Mississippi, many concrete crossings used by heavy automobiles and tractor-trailers depend on wood supports. These timber pilings of southern pine are hardly ever seen or noticed, but over the years, many have become cracked and weathered by the ever-moving water table and baked by the pudding-thick Mississippi heat. These bridges may only connect roads over a small ditch or a dried creek bed, hardly noticeable for the few feet of support they provide, but those gullies are commonplace in this floodplain.