The L.A. City Council on Friday approved a five-year, $2 billion project labor agreement that requires contractors on nearly 100 current and future public works projects to hire union workers.

The agreement, the largest in L.A. city history and one of the biggest in the nation, also requires contractors to hire 30 percent of their project workers from local communities. It applies to 98 Department of Public Works projects, including massive sewer repair and construction and street repairs.

The 12-0 council vote, which came after 45 minutes of favorable comment with no dissenting voices, is a major victory for building trades unions that have been pushing for the agreements. In exchange for requiring contractors to hire workers from union hiring halls, the unions promise no labor disruptions.

But the agreement represents a blow to non-union contractors who have been trying to stop the spread of the labor agreements. They contend the pacts make bidding on contracts prohibitively expensive by requiring them to pay into a special fund that provides health and pension benefits for project workers, even if the contractor already provides benefits.

A statewide coalition of non-union contractors has won voter approval for bans on project labor agreements in the San Diego County cities of Chula Vista and Oceanside and is considering whether to push for similar bans in L.A. County.