Mountain View's top fire official, who ushered in greater cooperation among the hodgepodge of South Bay emergency agencies, announced last week he would retire after five years on the job. Fire Chief Brad Wardle informed the city's administration last week that he needed to end his 29-year firefighting career in order to move to Utah and take care of his infirm mother.

The 51-year-old Wardle joined the city's fire department in 2010, at a time when cities across the South Bay were reeling from recessionary budget cuts. But the belt-tightening also presented a "perfect storm" for changing long-held practices among the fire departments, Wardle said.

Up until recently, firefighters would respond to incidents outside their jurisdiction only in major cases, such as a large fire or accident. City fire crews each had marching orders to take care of lesser incidents only within their own boundaries.

Wardle gained a position to elicit some change in 2012 when he was selected as president of the Santa Clara County Fire Chiefs' Association. He helped broker an agreement among the cities to have their individual fire departments respond to smaller incidents outside their boundaries if units were nearby.

Before he joined the Mountain View Fire Department, Wardle served as fire chief in West Jordan, Utah, where such partnerships were more commonplace. Its wasn't a hard sell; many other Santa Clara fire chiefs were receptive to working together more, Wardle said.

"Throughout Santa Clara County all the fire chiefs embraced this to a certain level," he said. "We've essentially dissolved the borders between our cities, and we're working seamlessly together and sharing resources."

Additionally, fire departments made an agreement to phase out incompatible radio equipment operating on different frequencies. Many departments are in the process of purchasing newer models that can use a wider radio spectrum.

Wardle described leaving Mountain View as a "bittersweet pill to swallow" because he came to appreciate the community as well as the professionalism of the city's workforce.

"I really enjoyed my time in Mountain View, but family is what's important and that's what's taking me back to Utah," Wardle said.

In the coming weeks, Mountain View will begin scouting for a new fire chief to fill Wardle's position. The city will hire a public-sector search firm to find suitable candidates, said City Manager Dan Rich in an email. The process will likely take six months.

In the meantime, Deputy Chief Juan Diaz will take the helm. Diaz, 49, was hired by Mountain View last year after a 25-year career in firefighting, mostly at the San Jose Fire Department.

Speaking to the Voice on Tuesday, Diaz said he hoped to continue the effort to bring "inter-operability" to South Bay fire departments.

"We're not 100-percent finished, but we're heading in the right direction," he said. "My vision is to continue the initiatives that were started by Chief Wardle."