SALEM — The state announced plans yesterday to build a $106 million court complex on Federal Street that will keep Salem the judicial center of the North Shore for years to come.

Standing in a spitting rain outside a pre-Civil War courthouse, Lt. Gov. Kerry Healey told an enthusiastic crowd of city officials, judges and local business leaders that the state is making a major commitment to rebuild its decaying court system.

"We are very proud to be able to make this investment not only in Salem, but throughout the commonwealth," Healey said of the $350 million the state plans to spend over the next five years to build and renovate courthouses in Salem, Fall River, Lowell and Taunton. Projects are already underway in Worcester and Plymouth.

The news was greeted enthusiastically in the city, no more so than at The Salem Partnership, a local business lobby that has campaigned for new courts for more than a decade.

"It secures Salem's downtown for the next 100 years," said Joseph Correnti, president of the Partnership.

In Salem, where nearly one-third of the state funds will be spent, a mega-courthouse will be built next to the First Baptist Church, which is at the end of Federal Street near North and Bridge streets. The state plans to incorporate the church into the courthouse. The large court building would hold the Superior, District, Juvenile and Housing courts and have 16 courtrooms.

As part of the project, the church would be acquired along with three houses on Federal Street. The Baptist Church had been for sale but was taken off the market more than a year ago. In a recent interview, a church official said state officials had not spoken with them, but the church would consider an offer if it provided enough money to buy a new church building.

The state will acquire additional land by reconfiguring the traffic interchange at the corner of North and Bridge streets.

The Probate and Family Court, which is next to the Baptist Church, will be renovated. The Registry of Deeds, which currently shares the building, will be moved out, to an undesignated location, to provide more space for the Probate Court.

Two of the city's busiest court buildings — Superior Court on Federal Street and District Court around the corner on Washington Street — will be sold for redevelopment. The superior and district courts will be housed in the new court complex, along with the Juvenile Court, which now occupies rented space in the Shetland Park office complex near Pickering Wharf. The Housing Court, which is a circuit court that moves around to different courthouses in the county, will get a permanent courtroom in the new complex.

Although a timetable has not been finalized, the state hopes to begin construction next year and finish by 2009, according to David Perini, commissioner of the Division of Capital Asset Management, the state agency in charge of construction.

The court project, he said, will be coordinated with the MBTA's plan to construct a 1,000-car garage at the commuter rail station. Of those spaces, 300 are expected to be reserved for court employees.

Yesterday's announcement was kept secret until the last few days. Mayor Stanley Usovicz sent out word on Sunday to city councilors and other local officials.

There was speculation a few days ago that Gov. Mitt Romney was going to announce the restoration of only $3 million in design funds, which had been announced last winter and then just as quickly taken off the table. When it became clear that this was the major funding commitment the city has been anticipating for more than a decade, there was a lot of excitement in the small crowd that gathered to hear the news.

Building a major new courthouse in the city is important, officials said, because the courts, law offices and related businesses provide more than 2,000 jobs and contribute millions of dollars to the local economy.

"It stabilizes an employer ... that is the second-largest in the city," Usovicz said.

"The courts are the heart and soul of the city," said state Rep. John Keenan, D-Salem.

State officials stressed that this is the final state approval needed and that the funding proposal does not have to go before the Legislature. The funds are part of the governor's $1.3 billion capital budget, which is drawn from bonding money that was previously approved by the House and Senate.

"It's a go," Perini said.