OAKLAND -- Several times in recent months, police have been unable to radio their dispatchers from numerous "dead spots" across the city, including major intersections like MacArthur Boulevard and Seminary Avenue, or the trauma ward at Highland Hospital, where shooting victims are often sent.

That changed over the weekend with the official switch Sunday to a new radio system for police and fire departments called Platform 25, or P25. Top Oakland officials hailed the upgrade as a stride forward for the city and a major step in coordinating the entire Bay Area for when -- not if -- the next natural disaster strikes.

Dead spots still exist in the city, and one of the city's three major radio towers is yet to be upgraded, officials cautioned, but the change is "a huge improvement," said Lt. Carlos Gonzalez, who heads the police department's radio room.

"For our officers, they can use their existing radios," he said. The equipment changes are all in central communications locations, rather than in individual patrol cars.

"They just have to switch to a new channel, so it's a seamless transition," Gonzalez said.

The police radio system had come under fire after a series of highly publicized communication breakdowns. A two-hour breakdown in April forced officers in the field to get their dispatch information on their cellphones.

Though repairs were made quickly each time, the problem kept recurring. Until now, a blanket fix was tricky, Oakland Mayor Jean Quan said, because the causes of the problem kept changing and "nothing was consistent except it was a very old system."

The new system uses digital sound, an upgrade from the existing analog equipment, and has stronger antenna service, technicians said. Perhaps most importantly, it can be accessed by anyone using a similar system.

Oakland joined forces with other local agencies, including the Alameda County Sheriff's Office and agencies in San Francisco, San Jose and Santa Clara County, to transition together to P25, but is the first city in the area to make the change, Oakland Emergency Services Director Renee Domingo said. Two towers were fully upgraded and a third, in the Oakland hills, will be upgraded in the next six to 12 months, she added.

The new infrastructure and equipment, much of it purchased years ago, cost about $18 million total, and installation was funded by federal grants, according to Quan.

Oakland is the first city to get the system installed, she added, because "we started sooner," having begun to lay groundwork for P25 after the 1991 Oakland firestorm and the 1989 Loma Prieta earthquake.

Quan said the plan is to get all Bay Area cities using the system by 2013. Every city or agency that adopts the system can be in real-time communication with any other, making coordination in the event of a disaster much easier, she said.

For now, the city is working on a two-to-three-week period of "refinements and adjustments," Oakland Information Technology Director Ken Gordon said.

He said the city is also still trying to map where radio "dead spots" remain, with hopes of eventually getting rid of them entirely.

Contact Sean Maher at 510-208-6430.