SANTA ROSA -- The city of Santa Rosa’s urban growth boundary could be extended for more than two decades if voters approve a measure backed unanimously by the City Council.

Earlier this month, the council agreed to seek voter approval in maintaining the current boundary to 2035. It doesn’t expire until 2016, but the council proposed the extension so that the boundary would be in line with the city’s General Plan, which also expires in 2035.

The boundary is a means for cities to designate what it is urban versus rural, and limits the city from appropriating portions of property beyond city limits. Development projects beyond city limits typically need voter approval, and expansion of services such as water and sewer services are limited.

Placing the issue on the ballot will cost between $20,000 and $40,000, the council said.

Meanwhile, Petaluma has a similar measure on the November ballot. Its urban growth boundary, approved by voters in 1998, would extend through 2025, the same year as the city’s General Plan.

And Cloverdale, the only Sonoma County city without an urban growth boundary, is also seeking a similar measure for the November ballot after months of debate.