Vashon voters are being asked to approve a modest property tax increase to replace the region’s aging emergency radio network.

The tax, if approved, would raise property taxes in King County by 7 cents per $1,000 in assessed value for 9 years. The projected $273 million raised would allow a consortium of emergency responders in King County to replace the radio network used by police, firefighters and other first responders.

The measure has broad support and is endorsed by a range of officials, including King County Executive Dow Constantine, Sheriff John Urquhart and the mayors, police chiefs and fire chiefs of cities and towns across King County.

On Vashon, the radio network is used for the dispatch of and communication between firefighters and medical responders with Vashon Island Fire & Rescue, as well as deputies with the King County Sheriff’s Office.

“Everybody supports the fact that we need new and upgraded emergency radios,” said Rex Stratton, a commissioner at Vashon Island Fire & Rescue (VIFR) who is familiar with the projects as a member of the executive committee of the King County Fire Commissioners Association.

Stratton and other proponents of the measure say King County’s current emergency radio network is badly in need of replacement because it is over 20 years old. Those familiar with the network say the system of radio towers, personal radios and other infrastructure works well now but is at greater risk of failing as it ages and won’t be easy to repair in the future. The vendor that supplies replacement parts for the network, Motorola, will no longer do so by the end of 2018.

The system was also designed when King County had a smaller population, and its capacity can be strained at times.

While VIFR Chief Hank Lipe said law prohibits him from promoting the measure, he noted he has been aware that the system is aging and will need replacement. The King County Fire Chiefs Association, which Lipe is a member of, did formally endorse the measure.

“A radio system that does not have a high level of reliability puts responders in a very difficult position,” he said.

Stratton said that while VIFR’s commissioners support the measure, they do take issue with how King County has planned the project. Small fire district such as VIFR were not invited to give input, he said. And had VIFR given feedback, officials there likely would have expressed concern over the county’s funding mechanism, which, if approved, will allow King County to raise the limit on property taxes it can collect by 7 cents, possibly cutting into tax funding needed by local agencies.

Authors of the statement against the measure in the voter’s guide echo the same concern, saying that if property values suddenly drop, some fire districts may find themselves unable to raise their tax rates and be forced to lay off staff.

Stratton said this would potentially affect just two or three fire districts in the county, and the county has provided some protections against it. Both he and Lipe said that because VIFR collects far less in taxes than it legally could, Vashon’s fire district is not at risk.

“That would not be a concern here,” Lipe said. “We’re not at our maximum cap.”

Still, Stratton said funding the radio system with a bond rather than a levy may have alleviated the concern altogether.

“I don’t mind taking 7 cents away from our money, but I want to have a voice in it,” he said.

King County Council-member Joe McDermott, who represents Vashon, said the county considered the effect of the new tax on small fire districts, but doesn’t believe property values will drop enough in the next nine years to pose a problem. He said the county needs to get moving soon on replacing the system, which will be built by Motorola and owned by a nonprofit governed by representatives of King County, the City of Seattle and the Valley Communications Center.

“Not doing anything would have grave consequences,” McDermott said. “We want our fire, police and other first responders to be able to communicate with each other.”

VIFR’s commissioners declined to sign an interlocal agreement formally approving of the measure to express their unhappiness with the process, but Stratton said they still hope voters will say yes.

“We need to get it done,” he said.

King County Elections will mail ballots this week. The measure, Proposition No. 1, requires a simple majority of over 50 percent to pass.