The Sonoma County Board of Supervisors Tuesday formally approved a $1.37 billion budget for the 2013-2014 fiscal year that begins July 1.

The 5-0 vote affirmed the board's discussion and preliminary endorsement Monday of the spending plan. It increases overall spending by 6 percent and grows county staffing by 4.7 percent, largely in health and human service and public safety departments.

It maintains about $16 million in county discretionary spending on road upkeep and supports two long-proposed computer system upgrades but postpones investment in many other program areas. Spending in most county departments is set to remain flat or see minimal growth.

The budget, including a $398 million general fund, is the first in five years to project a rise in discretionary spending. It assumes a .75 percent increase in property tax revenue and a 3 percent increase in county sales tax receipts.

Board Chairman David Rabbitt called it a "cautious budget."

"I'd certainly rather stay on the conservative side than roll the dice," Rabbitt said. "It is putting us in a stronger fiscal position."