The city of Roseville will annex some 3,800 acres west of its existing boundaries under a proposal before the Placer County commission charged with drawing political boundaries.

With a staff endorsement, and the backing of both Roseville and the county, the Placer County Local Agency Formation Commission is expected to approve the annexation at its meeting Wednesday.

Once developed, the Sierra Vista and Reason Farms neighborhoods, 2,075 acres and 1,754 acres, respectively, are expected to add hundreds of thousands of square feet of retail, 12,000 new housing units and 30,000 new residents to the city.

The annexations are facing opposition from one group of property owners, but an often powerful opponent of development will not stand its way.

"We are less interested in individual projects and more interested in the big picture," said Terry Davis of the Sierra Club's Mother Lode chapter.

The long-stalled annexations are on the fast track after the city and the county agreed on how to split revenue from future development.

The annexations are set for a 4 p.m. hearing Tuesday before the Placer LAFCO at the county supervisors chambers, 175 Fulweiler Ave., in Auburn.

Under a tax agreement approved unanimously in separate city and county votes, the county will receive 18.25 percent of future property taxes and at least 11.5 percent of sales taxes generated in the annexed areas. The share of sales taxes received could be adjusted to 16 percent, depending on the county's fiscal position in 2026.

According to County Executive Tom Miller, it could be as long as 30 years before the two areas are built out.

The annexations have been thoroughly studied and fit the commission's criteria for approval, said Kris Berry, executive officer of the Placer County Local Agency Formation Commission.

The commission looked to ensure that the annexations are a "logical growth area for the city," she said, noting that the city has the capability to provide services and the land was not prime farmland.

A commission analysis found that if Roseville continues to grow at its current rate, residential property will be built out in seven years, Berry said.

She noted that the majority of the land to be annexed has long been in the city's sphere of influence – or likely growth area. As part of the annexations, the 3,600-acre Sunset Industrial Park area will be removed from Roseville's sphere of influence.

Berry said she has received only one letter opposing the annexation in advance of the hearing.

A group of landowners has sued the city, asserting that all of the affordable-housing requirements for the Sierra Vista project have been allocated to their 81-acre parcel.

The Sierra Club's Davis said his group hopes to fight far fewer project-by-project battles. The Sierra Club has been working with the county on wider conservation plan. Once the plan is in place, the county would have a clear road map of where development would occur and environmentalists would get a protected contiguous wildlife area.

Davis said he hoped that Roseville would get on board with the plan. He said the Sierra Club was not opposing the annexation because it has long assumed Roseville would absorb the area.

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