The District government plans to sell more than 1,400 privately owned properties, including vacant lots and occupied houses, at public auction next month because landowners have failed to pay bills for such things as sewer and water service and city-ordered cleanup work.

According to city officials, the July 21 real estate auction will be the first to be held for reasons other than delinquent property taxes.

More than half of the properties listed yesterday in the classified advertising section of The Washington Post had liens placed against them under the city's tough, year-old Clean It or Lien It program, which was designed to force property owners who own vacant lots to maintain them and to force those who own abandoned buildings to secure them. When owners apparently failed to do so, the city's Department of Public Works sent crews to their properties to do the work on overtime and then billed the owners. If the bill was not paid, the city listed the property for public sale.

Although city officials maintained that all property owners had been properly notified of the violations and later of the money owed for the work, some owners contacted by The Post said they were surprised by their auction notices. Owners can pay off the liens before the auction, city officials said.

Ann Cahill, spokeswoman for Greater Southeast Community Hospital, said the first notice the hospital had received about the two vacant lots it owns on Robinson Place SE was through an inquiry from the press.

"We were unaware that there was a problem," she said. "The property was donated to us last year, and we thought it was clear of any liens. We are checking now to see what happened."

William Thurston works two jobs to pay the $1,000-a-month mortgage on his well-maintained row house, which is enhanced by a front yard rose garden in the Congress Heights neighborhood. Yesterday, he was at a loss to explain how his house ended up on the auction list for an unpaid bill of $34.92.

Alfred L. Richards, deputy chief for assessments of the Finance and Revenue Division, said Thurston and several of his neighbors had been billed for "basic cleaning of a lot, removing weeds and trash."

"I might have missed a notice," Thurston said as he sat in his living room, which is filled with family pictures. "But I just don't understand. It never got so bad here that the city needed to come in here and clean up."

Thurston said he would pay the bill rather than lose his house.

The Coalition for the Homeless owns several properties in the District, including two on Anacostia Road SE that showed up on the city's list.

Coalition Executive Director Pat Makin said her organization had received a bill for cleaning up a property at 1320 Anacostia Rd. SE and an adjoining lot.

"We have our own staff to maintain our properties, so when we got the bill we thought it was an error," she said. "The Department of Public Works has been outstanding with this organization, and I am sure this matter will be resolved satisfactorily."

Some city residents are happy about the upcoming auction. Shaw resident Tom Bandy lives next to a vacant lot at 925 M St. NW that was listed yesterday. The owners of the lot could not be reached for comment.

"It has been a constant source of dirt," he said of the narrow lot sandwiched between his frame house and an alley. "People abandon cars there, and prostitutes use it at night.

"I was delighted when the city came in with a front-end loader and cleaned it," he said. "And the auction means I now have a chance to buy it. The first thing I will do is put a big fence around it."