Windsor voters overwhelmingly approved a 22-year extension to the town’s urban growth boundary, endorsing a plan established in the 1990s to limit sprawl and focus development inside core areas.

Measure H won with 74.8 percent of the ballots cast in Tuesday’s election, which was conducted entirely by mail.

The measure expanded the area for development, adding three parcels totaling 22.5 acres and zoned for light industrial use. The additional parcels will allow existing businesses to expand their operations within the boundary, said Windsor Mayor Debora Fudge.

“This vote means that the boundary for Windsor will remain for the next 22 years,” Fudge said.

Fudge said the urban growth boundary is a necessary tool to protect local agriculture and to maintain the region’s rural quality, which she said gives Sonoma County its high quality of life.

“The last thing people up here want is to become another Silicon Valley, where the cities run into each other without any green spaces,” she said.

In 1998, Windsor voters approved Measure A, which established the 20-year urban growth boundary. The move was an effort to focus future development in existing developed areas of the town.

Measure A actually reduced by 300 acres the boundaries established when the town was incorporated in 1992. Fudge said the 22.5 acres added for development by Measure H still puts the town far below its original boundary.

“We’re really, really proud that the urban growth boundary is holding for 42 years,” Fudge said.

It was set to expire Dec. 31. Even if Measure H had failed, the policies establishing the current UGB would have remained in place. However, these policies could have been amended by a majority vote of the Town Council.

Passage of Measure H ensures that only a vote of the public can amend the UGB.

In other local election news, a parcel tax to fund education services in the Wilmar Union School District west of Petaluma was losing late Tuesday. Measure F, which would have imposed a $65 parcel tax for up to eight years, was supported by 64.3 percent of voters in preliminary results. It needed two-thirds for approval.

The parcel tax would raise $70,980 annually for the one-school district.