A proposed $6.9 billion Roads and Transit ballot measure will include a comprehensive study on linking the Burien, SeaTac, Tukwila and Renton by light rail.

An amendment by King County Councilwoman Julia Patterson, D-SeaTac, which recently was approved by the council, added the study to the Roads and Transit plan.

Funding for the road improvements plan would come from a one-tenth of 1 percent sales tax and a vehicle license fee of eight-tenths of 1 percent.

Proposed road improvements over the next 20 years are coordinated with a transit plan for investments in light- and commuter-rail, high-occupancy vehicle (HOV) pool lanes, park-and-ride lots, and express and local bus service.

Earlier, the Sound Transit board approved placing a $10.9 billion request on November ballot to fund the transit component, including expanding light rail north to Everett, south to Tacoma and across Lake Washington to the Eastside.

"We need better east-west connections in South King County," said Patterson, who serves as a member of the Sound Transit board of directors.

"As the cities of Burien, SeaTac, Tukwila and Renton continue to grow, improving travel between these cities becomes even more important. We need to make it easier to get around South King County, in addition to making it easier to get to major job centers like Seattle and Bellevue."

It will evaluate alternative light rail routes, stations, terminals and maintenance facilities connecting Burien, SeaTac, Tukwila and Renton. Additionally, the study will examine cost and ridership estimates for each of the route alternatives.

The Roads and Transit package would also fund construction of a transit center Burien.

Potential light rail alignments would connect the planned Burien Transit Center, the light rail station currently under construction in Tukwila at South 154th Street, the Tukwila Sounder commuter rail Station and the Renton Transit Center.

The Burien/Renton light rail segment could also connect directly to the Central Link Light Rail line, currently being constructed between downtown Seattle and Sea-Tac International Airport.

"With the information from these studies and the Roads and Transit investment in the Burien Transit Center, Southwest King County is well poised for future light rail extensions," said King County Councilman Dow Constantine, D-West Seattle, who serves as a member of the Sound Transit Board of Directors.

"Once light rail serving SeaTac Airport and downtown Seattle opens in 2009, the region will want to move as quickly as possible to add to the network."

"This comprehensive study means we are one step closer to fast and reliable transit service that will make it easier to get around South King County," Patterson added.

She also said the Roads and Transit plan, if approved by voters, would "make the most significant regional transportation investments since the freeway system was built 50 years ago.

"For years the citizens of this region ... have said, 'We are tired of Band-Aids and quick fixes. We want a vision for how the Puget Sound region is going to make real improvements to its transportation system."

Patterson called the Roads and Transit plan "the comprehensive approach to transportation that will make it easier for millions of people to move around this region whether you are in a bus, a train, a car pool, on a bike or driving alone. This is the plan voters have been demanding."