Walter S. Orlinsky, Baltimore City Council president for 11 years and a towering figure in liberal reform causes here, was sentenced today to six months in prison for taking thousands of dollars in bribes.

Choking with emotion, Orlinsky stood before U.S. District Judge Norman P. Ramsey in a courtroom crowded with friends and family and acknowledged his public career is now a "heap of ashes consumed by my own fires."

Ramsey imposed a prison sentence of four years but suspended all but six months. He then ordered Orlinsky to be placed on four years probation and provide a year's supervised "community service" after he gets out of prison.

Orlinsky, currently free on bond, must report to prison by Jan. 3.

Already stripped of his council presidency and disbarred from his law practice, Orlinsky does not know what he will do in the future, defense attorney Michael Kaminkow told Ramsey.

"Whatever I do with the balance of my life," said the 44-year-old Orlinsky, ". . . I will always be a convicted extortionist. . . so my dreams have died."

Orlinsky, customarily jovial and ready with a few quips for the press, slipped out a side door of the courtroom with his family, took a back elevator to the basement of the federal courthouse and left the underground garage by car.

He was originally indicted on charges of accepting more than $10,000 in kickbacks in exchange for using his influence to help Modern-Earthline Companies, a Philadelphia firm, obtain a contract valued at up to $47 million to haul Baltimore sewage sludge to Garrett County in western Maryland. The contract was cancelled because of objections by Garrett County officials.

On the eve of his trial last month, Orlinsky agreed to plead guilty to one count of extortion involving a cash payment to him of $2,532 in June, 1981--one of four such payments by Modern-Earthline lobbyist Edward J. Russell.

At his guilty plea hearing he acknowledged participating in the broader scheme, including his expectation of sharing almost $1 million in kickbacks with unnamed persons if the contract had gone through.

FBI officials say investigation of Modern-Earthline's dealings with the city is continuing.

At Orlinsky's sentencing today, three witnesses -- a black civil rights leader, an academician and a state judge -- spoke on his behalf.

Orlinsky was in the forefront of the civil rights movement in the 1960s, helping to tutor inner city youths and setting up athletic scholarships for them, said Lenwood Ivey, executive director of the Baltimore City Urban Services Agency.

Louis L. Kaplan, former president of Baltimore Hebrew College and founder of Beth Am Synagogue, to which Orlinsky and his family belong, said Orlinsky has already endured enormous public humiliation. His punishment should be guided "not by vindictiveness but by justice and mercy," Kaplan said.

Charles E. Moylan, a judge of the Maryland Court of Special Appeals, praised Orlinsky as a proud family man dedicated to public service.

With Orlinsky's parents, his wife and his son looking on, Moylan, described Orlinsky as a hero in a Greek tragedy -- "an otherwise true hero brought down by a tragic flaw."

Countering Orlinsky's array of witnesses, Assistant U.S. Attorney Stephen J. Immelt argued that Orlinsky's acts amounted to the "most unseemly sort of public corruption."

He recommended 15 months in prison and a $1000 fine.

The focus on his personal tragedy "tends to obscure the public tragedy -- his breach of public trust," Immelt said.

"This is not a victimless crime. All of us suffered."

Ramsey, in setting the six-month prison term, agreed Orlinsky should serve some time, but said he must also "return his talents to the community."

Thus, the judge said, he would require Orlinsky to submit a proposal to federal probation authorities for giving 2,080 hours -- 52 40-hour weeks -- of community service in Baltimore upon his release from prison.