A Seattle Department of Transportation contractor has begun preliminary work to prepare the route for the streetcar that is planned to run from Pioneer Square to Broadway via First Hill planned when it is completed in 2013. The “geotechnical investigation” will involve short duration street closures at a series of locations as the contractor extracts soil samples along the planned route.

The $132.8 million project is currently planned to terminate near the light rail station at Broadway and Denny that will begin operations in 2016. SDOT is looking at options for funding an extension of the route farther north up Broadway.

SDOT says construction of the line is scheduled to begin in “late summer and early fall in selected locations.” The core samples will help engineers to evaluate the existing pavement condition, the composition of underlying soils, and reaction to “loading” (bearing weight) in order to develop the details of the track and roadway construction.

The roster of sampling locations is below. You might encounter one to three hour lane and parking closures along the route through January 26, according to SDOT.

Parking and travel lane closures detailed below will be limited to the hours of 9 a.m. to 3 p.m. during the week and will be for periods of 2-3 hours at most:

• E. Howell St. from Broadway to Nagle Pl.

• Broadway from Pike to Union.

• Marion Street from Broadway to Boylston.

• E. Columbia St. from Broadway to approximately mid-block between Broadway & E. Cherry St.

• Broadway from Cherry to James.

• Broadway from E. Spruce St. for 140 feet (to the north).

• E. Yesler Way from 12th Ave. S. to 13th Ave. S.

• 14th Ave. S from S. Main St. for 140 feet (to the north).

• Jackson Street from I-5 to 10th Ave. S.

• Jackson Street from 5th Ave. S. to mid-block between 5th Ave. & 6th Ave.

• 8th Ave. S. from King to Jackson.