The Sonoma County Board of Supervisors on Tuesday approved spending up to $22.4 million to replace the county's 28-year-old accounting and budgeting system.

Supervisors said the costly upgrade to new computer software and hardware was needed to better manage the county's $1.28 billion budget.

"This is an investment for the future," said Supervisor Mike McGuire.

The upgrade will begin next month and is expected to be mostly finished by July 2015.

The spending includes: $946,000 for the new PeopleSoft program from Oracle; a $5.5 million implementation contract with Ciber, a Colorado-based firm; $6.2 million of county staff costs; $4.3 million in license fees, maintenance, training and hardware; $1.7 million in project management, legal services and audit oversight; and the remainder in contingency funds ($2.7 million), financing costs (up to $994,000) and administrative and supply costs ($778,000).

Financing from Oracle will cover at least $1.3 million this fiscal year, along with $3.9 million in county one-time funds. Future year costs could come from a combination of available funds, including departmental budgets and financing from the county treasury and Oracle.