The price tag for what was a $7.2 billion package of major new regional highways has risen by millions in the past year, leaving planners for a fall ballot measure searching for what to pursue and what to abandon.

The exact increase hasn't been calculated because a list developed a year ago didn't clearly define what projects would be built in the Interstate 405 and state Route 167 corridors. New cost estimates can't be compared with the original list in those cases, one state official said.

But new estimates circulated last week showed increases of more than $1.1 billion for just six of the biggest projects the Regional Transportation Investment District has on its list for King, Pierce and Snohomish counties.

The increases come as officials in South King and Pierce County are pushing the district to not cut back key projects and even increase amounts put into some of them.

The package, intended to supplement state highway spending, is expected to be on the November ballot and needs approval of voters in at least the urban areas of the three counties. The higher costs aren't expected to change the estimated $107 per-household cost of new taxes to help finance the projects but the higher costs could at least scale some projects back, if not eliminate any.

"We're trying to do as much as we can," said Julia Patterson, a King County councilwoman and a member of the district's executive board.

Costs have risen because of increases in the prices of steel and concrete, spurred by international construction booms, complex traffic and environmental requirements, and other issues.

The biggest individual cost increase was to upgrade the Ebey Slough Bridge on U.S. Route 2 east of Everett with a new lane and interchange improvements at Homemakers Road and state Route 204. The cost was estimated at $333 million three years ago but state engineers now think it would cost $847 million. Snohomish County is now suggesting a less costly project of ramp improvements to the trestle, but that, too, would cost more than the original project, said David Hopkins, regional coordination director for the state Department of Transportation.

Building a new state Route 509 connection to I-5 south of Sea-Tac Airport would cost $318 million more than thought in 2005, a 30 percent increase according to the latest state estimate.

The cost of a proposed cross-based highway at Fort Lewis is up $119 million since 2005, and the cost of widening state Route 162 between Sumner and Orting rose $106 million, or more than 50 percent.

Other examples include a $47.5 million increases in the price of widening and improving intersections on state Route 524 between Lynnwood and Bothell, and a $28.6 million increase in the cost of widening and improving intersections on a segment of state Route 531 east of Smokey Point. The state said the cost of widening state Route 9 from Clearview to Lake Stevens could be reduced by starting construction by 2010.

The costs of projects on I-405 and the state Route 167 segment between Edgewood and Renton also increased dramatically but the district has not specified the work to be done on those corridors and exact comparisons can't be made to last year's list, Hopkins said. The state has identified more than $2 billion in project on 405 but said $361 million in work could be delayed and other state money could be sought to get to the $1.3 billion total the district proposed spending on 405.

Similarly, the state now says it will cost more than $1.5 billion to add one lane in each direction to state Route 167 between Sumner and Renton but the district has proposed spending $420 million within that corridor. Cost estimates have increased dramatically for the Alaskan Way Viaduct and Evergreen Point Bridge, as well, but the district anticipated raising $800 million toward the Evergreen Point Bridge and $800 million for a tunnel replacement for the viaduct.

The district is considering scaling back the work on 167, and Patterson said if the viaduct is replaced with another elevated highway and the $800 million isn't needed "we have some money to spend elsewhere."

Last week several South King County and Pierce County officials urged the board not to cut money for projects such as 509 and 167, but to make sure they can be completed entirely. Several critics of the cross-base highway, at the same time, said the district should abandon the $453 million project because it will do environmental damage and create security issues at Fort Lewis and McCord Air Force Base.

Patterson and Shawn Bunney, Pierce County councilman and executive board chairman, said they expect projects to be cut back but not eliminated, since the list includes improvements to congested highways such as 405 and 167 and contributions to the cost of replacing Seattle's Alaskan Way Viaduct and the Evergreen Point Bridge.

'I don't see any projects being dropped," Bunney said. Using the 167 improvements as an example, he said: "How do you not do that?"

District board members, who are elected county council members in the three counties, expect on April 26 to approve a preliminary list of projects for public comment.