Santa Cruz County has announced that it reached a tentative agreement on an 11.5% pay increase for its largest union, representing more than 1,800 employees including parks, roads and social workers.

The contract still requires approval by the Board of Supervisors and members of Service Employees International Union Local 521.

The cost-of-living pay would be phased in over the three-year life of the contract. It would be the highest general wage increase in almost 10 years, the union said The county will also contribute 90 to 95 percent of the cost of employee health care.

In addition, more than 700 SEIU members would see supplementary raises through adjustments to job classification pay scales aimed at bringing the positions in line with those in similar governments, the county said.

“We fought hard for fair wages, increased healthcare benefits, and secured wage equity adjustments that reflect the dedication and hard work of county employees to promote strong recruitment,” Max Olkowski-Laetz, the president of the Santa Cruz County union chapter, said in a statement Friday.

The county said it was pleased by the tentative agreement.

“We strongly believe this tentative agreement provides a framework to further strengthen a workforce that meets the needs of the community,” county Administrative Officer Carlos Palacios said in a statement.

The county said the union is expected to schedule a membership vote this week.