The state Senate on Wednesday voted to raise the state gasoline tax by 9.5 cents a gallon and levy new weight fees on passenger vehicles to pay for an $8.6 billion spending plan over the next 16 years.

The vote was 26-22 in favor of the tax package and 31-17 for the project list.

Both bills, SB 6103 and SB 6091, now go to the House, where their prospects are uncertain. But Sen. Dan Swecker (R-Rochester), one of the chief proponents of the tax-and-build plan, said the seven Republican senators who voted in favor of the higher taxes would not have done so without private assurances that the House would follow suit.

“What swayed them was (Rep.) Helen Sommers saying she’d hold the House hostage until they passed the transportation bills,” Swecker said.

Sommers (D-Seattle) is chairwoman of the House Appropriations Committee, which writes the state’s $26 billion operating budget. She has said repeatedly that she and her fellow Seattle lawmakers can’t go home without a sizeable amount of state money to help rebuild the Alaskan Way Viaduct on Seattle’s waterfront.

The project bill passed by the Senate does include $2 billion for the viaduct, a project whose overall cost is estimated at $4.1 billion. The balance would have to come from regional taxes, federal funds and tolls. The Senate bill also earmarks $500 million for the $3 billion Evergreen Point floating bridge project, $992 million for Interstate 405 in East King County and $435 million to widen Interstate-90 across Snoqualmie Pass and protect the roadway from avalanche blockages.

Rep. Ed Murray (D-Seattle), chairman of the House Transportation Committee, said he has between 33 and 35 House Democrats in favor of the gas tax and project list, but still needs 15 to 17 Republican “yes” votes.

“It’s always more of a challenge to get votes in the House,” he said.

He said he hopes to have a vote later this week. The Legislature is scheduled to adjourn Sunday.

The Pierce County delegation in the Senate voted against the gas tax, some to protest what they considered too little money for projects in their communities, others because they wanted a public vote on the tax increases. Pierce County would receive about $500 million of the $7.2 billion that would be spent on state highway projects.

Sens. Mike Carrell (R-Lakewood), Rosa Franklin (D-Tacoma), Jim Kastama (D-Puyallup), Bob Oke (R-Port Orchard), Marilyn Rasmussen (D-Eatonville), Pam Roach (R-Auburn) and Debbie Regala (D-Tacoma) all voted against the gas tax measure. However, Rasmussen later switched her vote to “yes” when it appeared the gas-tax bill would fall short of passage.

Regala, as well as Sen. Tracey Eide (D-Federal Way), the Senate floor leader, voted against the taxes but in favor of the projects that would be built with the money.

In Pierce County, there would be $180 million to buy property for an eventual extension of Highway 167 from Port of Tacoma to a new interchange on Interstate 5, $125 million for car-pool lanes on I-5 in Tacoma, $146 million for car-pool lanes on Highway 167 between Puyallup and Auburn and $10 million for the Cross-base highway between Frederickson and Lakewood.

Sen. Don Benton (R-Vancouver) tried to persuade his colleagues to put the tax package on the ballot.

“Washington voters should have the final say on such a huge tax increase,” he said.

That motion was defeated on a 15-33 vote.

Benton also tried to get rid of the bill’s emergency clause, which said the bill takes effect as soon as it is signed into law. That provision insulates the bill from referendum, a signature drive that would seek to put the measure to a public vote.

“There is no emergency,” Benton said. “This is about stopping a referendum on this bill. That’s all it’s about.”

Sen. Erik Poulsen (D-West Seattle) disagreed.

“The viaduct slips every day,” said Poulsen, noting that 110,000 cars a day travel on the elevated structure that has been damaged by earthquakes. “This is a real threat. Lives are at risk and I don’t want that blood on my sleeves.”

Benton’s effort failed on an 18-30 vote.

how it would work

The current 28-cents-a-gallon state gas tax would rise by 9.5 cents to 37.5 cents a gallon by July 1, 2008 – 3 cents this year, 3 cents next year, 2 cents in 2007 and 1.5 cents in 2008.

Cities and counties would receive 1 cent of the new tax and share about $32 million a year.

New annual weight fees for passenger cars and trucks would take effect this year – $10 on vehicles under 4,000 pounds (Toyota Camry), $20 for 4,000 to 6,000 pounds (Ford F-150 truck), $30 for 6,000 to 8,000 pounds (Hummer) and $75 for motor homes.

New taxes will raise a total of $12.4 billion over the next 16 years, with $8.6 billion available for state and local projects.

Joseph Turner: 253-597-8436

joe.turner@thenewstribune.com