More than two-thirds of District government employees are in line to receive pay raises totaling 13 percent over four years, Mayor Vincent C. Gray announced Wednesday.

Gray’s administration has agreed to the raises for about 13,000 unionized employees working in about 30 city agencies, plus about 10,000 nonunionized workers. Police officers, firefighters and teachers are among those workers whose unions continue to negotiate contracts with the city.

City officials did not detail how much the raises would cost, but Gray (D) set aside $56 million in his recent budget proposal to fund potential raises through September 2014.

On Wednesday, the mayor said the new contracts will “meet the demands of a 21st-century government and a 21st-century workforce” and will help normalize relations with employees after many gave up raises in recent years as the economic slowdown battered the city budget.

“I call it righting an injustice that has been done over these last several years,” Gray said.

D.C. Mayor Vincent Gray (Sarah L. Voisin/The Washington Post)

Geo T. Johnson, leader of District Council 20 of the American Federation of State, County and Municipal Employees, praised Gray at a news conference held to announce the deals.

“When he made a commitment to make sure public employees were treated fairly, he meant that,” said Johnson, whose union represents thousands of city workers and was among the unions strongly backing Gray during the 2010 election campaign. “Hasn’t crawfished once on that.”

Johnson said the raises, while modest, are meaningful. During the recession, “most people did not get anything,” he said. “These people are ahead of a lot of people in the United States at this time.”

The first of four 3 percent raises — totaling 13 percent with compounding — is expected to become effective this month. But workers will not see additional money in their paychecks until the D.C. Council ratifies the eight contracts announced Wednesday.

Natasha Campbell, Gray’s labor relations director, said the new contracts will generally give management more flexibility in scheduling and will change the role of seniority in promotions and other personnel actions. Contract language, she added, strengthens the city’s right to declare a “reduction in force” if budget pressures or other factors make layoffs necessary.

Other provisions, Campbell said, include a “zero tolerance” policy on workplace violence and tougher restrictions on school bus drivers, who have come under scrutiny after recent incidents in which children were improperly transported.

Although the agreements announced Wednesday cover most of the city workforce, police, firefighters, medical staff members and school employees are among those who have yet to consummate agreements.

City officials portrayed negotiations with teachers and principals as nearing a close, but talks remain contentious between police and fire unions and the Gray administration.

The city recently entered mediation with the Fraternal Order of Police unit representing D.C. police officers, Campbell said, and mediation with the firefighters recently closed, with several matters headed for binding arbitration.

“There are more than one or two items” at issue, she said.

Ed Smith, leader of International Association of Fire Fighters Local 36, said his union and the administration are at odds over compensation and other issues — including whether the fire department can pursue a controversial change to its shift schedule.

Smith also said 3 percent-a-year raises are meager for employees who have gone seven years without signing a contract and who agreed to a two-year pay freeze.

“We’ll sit down and talk about anything,” he said. “But we need to get caught up, someway, somehow.”