The Contra Costa County Board of Supervisors decided Tuesday to allow 95 percent of future revenue from a sales tax passed by voters in November to fall under the purview of a 17-person community advisory committee, instead of the 50 percent proposed by one supervisor.

The still-to-be-named committee would only offer recommendations to the board, but the jump in scope was still significant, considering Measure X, the countywide half-cent increase in sales tax, is expected to generate at least $81 million annually over 20 years, beginning April 1.

Measure X passed in November by an approximate 58-42 percent margin.

The funds are slated to keep “Contra Costa’s regional hospital open and staffed; fund community health centers; provide timely fire and emergency response; support crucial safety-net services; invest in early childhood services; protect vulnerable populations; and for other essential services,” according to the measure’s wording.

After Supervisor John Gioia found board support to raise the committee’s share of advisory power from 50 to 95 percent, Supervisor Karen Mitchoff went along with her four colleagues. She initially said it was fair for community groups to trust the board to decide what to do with 45 percent of the money, but in the end wanted to minimize complaints.

“We get criticized and I get tired of it,” Mitchoff said.

The other 5 percent of Measure X funds will be set aside in a special interest-earning account for unanticipated needs, to be decided by at least four-fifths of the board.

The new committee will oversee an annual assessment of county needs, focusing on the priorities laid out by Measure X. It will also keep lists of the county’s top 10 service gaps. It will also provide annual reports on the funds’ impact.

The board directed county staff to come up with an official process for soliciting applications for the committee by its Feb. 9 meeting, with the goal of having it in place by mid-March. A separate oversight committee will also be assembled to make sure the funds are correctly collected as dispersed but won’t be discussed until May or June.