Klahanie residents may be voting themselves into Sammamish in less than three months.

The Sammamish City Council on Tuesday night unanimously passed a bill requesting an annexation vote for the planned community and its associated neighborhoods on the April 28 special ballot. If the King County Director of Elections accepts the ballot, the city will be on the hook for the cost of a local ballot for Klahanie residents and the printing of an informational pamphlet, as well as the appointment of pro and con committees.

Tuesday’s vote was the culmination of a year of formal preparation by the city — and perhaps more than a year of informal preparation by council members.

“This has ben a long, long process,” City Manager Ben Yazici said.

Klahanie, an unincorporated planned community on the Sammamish Plateau, was once claimed by the city of Issaquah’s annexation area. But after Klahanie residents narrowly rejected annexation for the second time in the Feb. 2014 special election — a similar vote failed in 2005 when Klahanie residents said “yes” to joining Issaquah but “no” to joining into its debt — Issaquah city officials hashed out a deal in April to transfer annexation rights to the Sammamish.

In the run-up to the Feb. 2014 election, members of grassroots neighborhood organization Klahanie Choice lobbied for Sammamish officials to fight to bring the area and its 4,000 households into the fold. Choice member Mark Seely, speaking at a Sept. 2013 Sammamish council meeting, argued Klahanie’s culture had more in common with Sammamish — geographically, economically and culturally — than Issaquah.

Councilman Ramiro Valderrama-Aramayo said it was fellow Councilman Don Gerend who took that argument to heart.

“While the success of getting here has many fathers … one member in particular kept this going and that was Councilmember Gerend,” Valderrama-Aramayo said. “One year ago he did envision this going forward.”

Klahanie is home to nearly 11,000 people and nearly 4,000 households, meaning Sammamish’s population will grow by more than 20 percent if Klahanie residents approve annexation.

Sammamish is currently taking applications for pro and con committees to write statements for the ballot.

In a press release sent Friday, Yazici made the case that an affirmative annexation vote would be beneficial to current Sammamish citizens’ commutes.

“Many of our residents have a tough commute along Issaquah-Fall City Road,” Yazici said. “Improving that corridor has been on our radar for a long time. Fortunately, if the Klahanie area votes in favor of annexation, the added revenue we’ll receive will make those improvements very affordable.

“The estimated cost for the initial improvements is $23 million. If the annexation goes through, we have committed to using $3 million of our current reserves for preliminary engineering and permitting costs. But the remaining $20 million could be paid for with the new revenue we’d receive from annexation.”