Residents in parts of south Charlotte could experience later mail deliveries beginning this week, with some areas possibly seeing deliveries after 8 p.m., the president of the local letter carriers union said.

John Walden, branch president of the National Letter Carriers Association, said changes in routes and the delivery process could eventually affect as many as 50 percent of Charlotte residents.

On Saturday, the U.S. Postal Service's Minuet Station, 430 Minuet Lane, cut 14 of its 67 routes, according the Postal Service. It's consolidating the remaining routes.

A note from an area mail carrier to his customers said the consolidation was "due to the deficit of the USPS budget and other changes in the post office."

Monica Robbs, spokeswoman for the Postal Service in Charlotte, denied that the changes were related to budget problems and said any adjustments were to make the post office more efficient.

Postmaster General Patrick Donahoe told U.S. lawmakers last week that the Postal Service could see a $10 billion net loss this fiscal year. An increase in competition and email use have resulted in the Postal Service delivering 20 percent less mail in 2010 than it did four years ago.

Robbs said the changes in Charlotte's delivery are because of the post office's new sorting system for magazines and large letters and its program to adjust routes to changes in a neighborhood.

The program is a nationwide effort between the Postal Service and the National Association of Letter Carriers to react to development in a neighborhood or changes in a neighborhood's mail volume.

If a neighborhood saw a decrease in population or mail, for example, the post office could extend the carrier's route to cover more addresses.

"There are some growing pains, and there will probably be some continuing adjustment as a result," Robbs said.

Robbs said that if deliveries are pushed back several hours, the post office will send postcards to its customers notifying them of the change.

Meanwhile, the Postal Service also has added a new automated sorting machine, which organizes larger envelopes and magazines by where they will be delivered.

The machine has allowed post office officials to extend delivery routes because some carriers are spending less time sorting mail by hand.

But the Postal Service is eliminating too many routes and overextending others, said Walden, the association branch president.

He said the Postal Service recently cut around seven routes from its Carmel Road station, located near Pineville Matthews Road.

"They did have carriers out until 9 at night because the routes were so screwed up," Walden said.

Because the new sorting system will affect mail going to about 50 percent of Charlotte's residents, he said those in other parts of the city could expect the same delivery changes, at least until the Postal Service returns some of its eliminated routes or reconfigures some of its consolidated ones.

But that could take several months. After 60 days of delivering the mail by the new routes, the Postal Service will review the delivery data, including carriers' time spent in the office and on the street, and possibly make changes.

"It should get better, but it might not get better for a while," Walden said. "It's something they'll have to work through."