Plans for a new Sonoma County courthouse are moving forward, but a scaled-down budget and a delayed schedule are expected to push construction back another year to 2015.

The revisions, driven by state funding woes, are expected to trim more than $15 million, or about 10 percent, from the construction budget, reducing the total estimated cost to about $166 million.

Design work was set to begin this year on the six-story, 173,500-square-foot facility on the county administration campus in Santa Rosa north of Steele Lane. Now it could begin next summer.

The revisions came as part of an endorsement the project earned last week from a panel of local and state judges tasked with deciding which court projects to fund statewide and which to shelve amid the state's fiscal crisis.

"It's a very difficult time for the courts," Sonoma County Superior Court presiding judge Rene Chouteau said Tuesday in an update to the Board of Supervisors on the project.

Court officials say the new facility, planned on the site of the former county jail, is needed to replace the 47-year-old Hall of Justice, which officials say is outdated, undersized and cannot be renovated to serve court needs. Those needs include modern security features, larger jury assembly and deliberation rooms, in-custody holding areas and adult and children's waiting rooms.

Chouteau and Supervisor Shirlee Zane were among several local officials who lobbied for the project in San Francisco last week during several days of hearings for the panel of judges, called the Court Facilities Working Group.

Of the 31 projects in the running, the panel recommended 23 projects go forward, including Sonoma County's courthouse. Seven others were recommended for indefinite delay and another project left to a separate advisory body to review.

A final decision is expected next month from the state's judicial council.

"At least at this point we have the green light to go forward," Chouteau said.

Superior courts are a state division, and the money to fund court renovation projects comes from bonds paid for with criminal justice penalties and fees.

Gov. Jerry Brown complicated that funding picture this year when he shifted $240 million of the $310 million available for court projects in 2012-2013 to help fill the state's budget gap. The same move spelled out future funding grabs of $50 million annually.

The reductions prompted the panel of judges to recommend a smaller number of projects for continued funding. The panel also recommended tighter budgets for each.

For Sonoma County, the $15.4 million reduction could result in fewer courtrooms, fewer holding cells for inmates or other changes in construction, court officials said.

Preliminary plans had called for 15 criminal courtrooms, 450 above- and below-ground parking spaces and consolidated criminal, traffic, juvenile dependency and probate proceedings.

The project architect is New York-based Richard Meier & Partners, the firm that designed The Getty Center in Los Angeles and the Barcelona Museum of Contemporary Art, among other notable structures.

Estimated design and engineering costs amount to more than $8 million, officials said.

The state purchased the 6.8 acre property from the county this year for the bargain price of $5.2 million. The purchase included the former jail site and two sites to be used for parking, the 3-acre county Fleet Building site on Ventura Avenue and a 1.3-acre parking lot on Russell Avenue.