Property owners in Sacramento's Natomas basin have voted overwhelmingly to pay higher taxes in order to finish a massive repair of levees protecting their community.

In results announced Friday, a proposed property tax increase passed with 84.5 percent approval in a vote-by-mail held by the Sacramento Area Flood Control Agency.

The assessment will cost the average homeowner about $60 a year for as long as 40 years. The money will support bond sales of $40 million to continue a levee improvement project that has been under way since 2007.

Commercial properties will see increases of about $41 per 1,000 square feet, while the increase for industrial parcels will average $26 per 1,000 square feet.

"I don't think it's a particularly popular thing to do to assess yourself," said Angelique Ashby, a SAFCA board member and Sacramento City Council member representing Natomas. "I'm extremely proud of my community for understanding the importance of this assessment."

About 12,400 ballots were received, representing 39 percent participation. Ballots were weighted according to parcel size, according to the rules of Proposition 218.

The entire Natomas project began in 2007 and will raise and/or widen 42 miles of levees surrounding the basin. The work was required after a study by the U.S. Army Corps of Engineers revealed a heightened risk of seepage through numerous levee sections.

The project will produce some of the strongest levees in the state, protecting about 80,000 Sacramento residents and infrastructure that includes an international airport, a sports arena and two interstate highways.

"This is the largest public safety project we have in the region," said Sacramento County Supervisor Phil Serna, also a SAFCA board member. "I'm delighted by the results."

The project's total cost is estimated at $780 million. That price tag has roughly doubled since 2007, SAFCA officials said, because of design changes mandated by the Corps of Engineers.

In 2008, the Federal Emergency Management Agency revoked the basin's 100-year flood certification, resulting in a flood-insurance mandate and a building moratorium that remain in place.

SAFCA hopes to get those requirements lifted in 2012 by satisfying a complicated federal formula. A key component is finishing 18 miles of levee repairs by the end of this year, and also demonstrating a local funding match for the work that remains.

That is one reason SAFCA officials said approval of the property tax increase is needed now, even though the additional assessment will not be imposed until the 2013-14 fiscal year.

The remaining 24 miles of levee upgrades will be completed under the direction of the Army Corps, but congressional approval is required before that work can begin.

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