San Pablo officials are rightly concerned about the future of emergency medical response residents receive from the county's largest fire district, but the city's unilateral proposal is premature and poorly conceived.

That's why voters should reject Measure K on the June 3 ballot, a proposed permanent quarter-cent sales tax increase for emergency medical services. It would raise the city's sales tax for the second time in three years, this time from 9 percent to 9.25 percent, making it one of the highest in the East Bay.

To be sure, San Pablo City Manager Matt Rodriguez and the City Council deserve credit for their proactive attempt to protect timely emergency response. And their notion of a separate medical squad at the city's only fire station merits serious consideration -- especially because Doctors Medical Center, located in the city, could close soon.

But San Pablo is part of the much-larger financially struggling Contra Costa Fire Protection District, which must revamp its fire and medical response model for its entire service area. The vast majority of calls are for medical aide, rather than fires. That's why the idea of separate medical squads at fire stations is part of that districtwide discussion, although the cost-savings remain uncertain.

The biggest problem facing the fire district is its exorbitant salary and benefit costs. San Pablo's plan could perpetuate that because it would rely on highly compensated firefighters and captains staffing the medical squads.

The sales tax plan also presents financial problems for the city. Measure K would raise an estimated $600,000 a year. But the promised emergency medical team would cost roughly double that, perhaps even more. The city would have to make up the shortfall out of its fragile general fund.

Two years ago, city officials convinced voters to hike the sales tax a half-cent on the dollar to help bolster that general fund. We supported that ballot measure. Now the city essentially would need half or more of that earlier tax hike and the entire new one to fund the emergency medical services proposal.

It's a huge commitment that might make sense at a different time. But the city should not be making a permanent promise to residents when it has not even hammered out the details of an agreement with the fire district to provide the emergency medical service. It has no assurance the district will use the money efficiently.

We recommend city officials bring back a temporary tax proposal for the November ballot with clear restrictions on how much the emergency medical service will cost and how it fits into the yet-to-be-seen fire district reforms.