Next time you complain about paying 44 cents for a stamp, consider the process that takes a piece of mail to its destination.
A letter that starts at your mailbox or a blue U.S. Postal Service box on the curb travels first to the Charleston Processing and Distribution Plant on Cross County Road. There, in a cavernous assembly line with a dizzying network of pipes and ducts, everything coming from ZIP codes starting with 294 begins a journey.
First, the mail enters a purple feed machine that the workers affectionately call "the Barney system." From there it heads to another conveyor belt that squeezes air out of the mail and tests it for anthrax -- at the rate of 25,000 letters per machine every hour.
Then it's on to the computers that electronically read where the mail should go. They take photos of illegible addresses and send them to Greensboro, N.C., where
workers manually interpret our lousy handwriting.
More computers tag the letters by destination, then send them to sorters that process and prepare the mail for trucks and planes. All the while, federal inspectors watch from catwalks above the plant, taking in the operation from two-sided mirrors better identified with police interrogation rooms.
"A letter may be considered a low-tech item these days, but the way we sort and deliver it, it's definitely not low-tech," said Columbia-based communications coordinator Harry Spratlin.
Yet despite its own technological advances, the centuries-old Postal Service faces its greatest challenges ever. In 2000, only 5 percent of Americans paid their bills online, according to Spratlin. Now, 50 percent do.
Tack on union requirements that the Postal Service can't meet financially, and it becomes an American institution with an unknown future.
Postmaster General Patrick Donahoe told a U.S. Senate committee this week that the agency faces default unless lawmakers enact change this month. The Postal Service must make a $5.5 billion payment to pre-fund retiree health benefits, but it lacks the money to do so.
Donahoe asked for a law that would resolve that requirement and return retirement system overpayments. He wants the Postal Service to determine how often it delivers mail and how it structures its health care.
The Postal Service cut $12 billion in costs and 110,000 workers over the past four years, but it needs to reduce its annual costs by an additional $20 billion and another 220,000 people over the next four years to become profitable again.
The Postal Service also needs Congress' help to make those workforce cuts, otherwise prohibited under union agreements.
The processing plant in North Charleston is one of four operations across the state. Those places are safe. What aren't are the smaller, rural post offices with lower revenue and lower volumes of mail.
A study that began in July will look at keeping or closing 20 post offices across the state, including some in the Lowcountry: Cordesville and Russellville in Berkeley County, Grover in Dorchester County and Williams in Colleton County.
First-class, single-piece mail in the greater South Carolina district fell about 13 percent in the first three quarters of this year, according to Spratlin, and the future looks no better. Mail volume peaked nationally in 2006 at 213 billion pieces, he said, but that number should fall to 150 billion pieces in the coming years.
The North Charleston plant handles outgoing mail from 4 p.m. to midnight and deals with incoming letters from 9:30 p.m. to 6:30 a.m. With that incoming mail, the plant's workers and machines create "walk sequences" for letter carriers, meaning they can walk down the street and drop letters into mailboxes in perfect order.
That's virtually the first time the mail touches human hands these days, despite the buzzing, honking factory and the 925 workers who make it run.
"We do almost nothing by hand," said Operations Support Specialist Victor Gibson. In fact, according Spratlin, the Postal Service would need 600,000 more employees to accomplish the daily dance without machines that handle tens of thousands of pieces of mail every hour.
Reach Allyson Bird at 937-5594 or on Twitter at @allysonjbird.