Project of the Week - Alaskan Way Viaduct crews battle old railroad ties, concrete and debris to halt settlement
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Crews, working in a tight spot under the Alaskan Way Viaduct, have completed a project to stabilize four sinking column footings. |
Last fall, crews began work on the Alaskan Way Viaduct to stabilize four sinking viaduct footings between Columbia Street and Yesler Way. This week, crews will place concrete around the fourth and final column foundation. This project is the first of six Moving Forward projects to repair or replace about half of Seattle’s Alaskan Way Viaduct.
The repairs involved drilling a series of new supports called micropiles into stable soil. The micropiles are about eight inches in diameter, about 75 feet long, and are reinforced with grout and a large steel rod in the center. When tied into the existing column foundation, the micropiles create a wider and stronger structure that will arrest further settlement of the viaduct in this location.
Construction crews encountered many obstacles throughout the project. Since the viaduct was constructed on fill, crews first had to drill through loose dirt comprised of old concrete debris, sawdust, railroad ties and old piling from the timber trestles. They also had to be careful not to hit existing utilities that lie beneath the surface. Water was another difficulty crews had to deal. A series of well points were installed around each of the two southerly footings. Careful pumping was required to keep the water level low enough for the workers to place rebar and concrete, and yet not draw down the water table in the area to cause settlement of the nearby buildings.
WSDOT began the work because the footings in this location continued to sink gradually; they have settled approximately five-and-a-half inches into the ground since the 2001 Nisqually earthquake. This is a temporary repair of a short section of the structure to keep the viaduct safe for drivers until this section of the viaduct is taken down in 2012.
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Maintenance and Operations Feature - Litter cleanup improves safety
Maintenance crews plant maple trees along the I-5 Bridgeport Way off ramp on a recently enhanced slope. |
One person’s trash is another’s treasure. WSDOT Tacoma maintenance has found this to be true with street sweepings, such as litter, which is treated and used to create a safer and more beautiful roadway.
Instead of paying expensive landfill fees to dispose of waste, WSDOT screens glass, metals and pieces of tire through a filtering system. Using what is left, mainly dirt and sand, crews gradually fill steep slopes within permitted areas along state highways. The treated dirt and sand is graded, covered with fertilizer and hydro seeded, and then landscaped. Recently, Tacoma maintenance teamed up with WSDOT's Olympic Region Landscape Office to plant red sunset maples along state right-of-way at the I-5 southbound Bridgeport Way off-ramp.
This method of recycling is not only cost effective, but motorists benefit as well. By flattening steeps slopes, a car that exits the roadway has a chance to recover instead of rolling over. This roadside improvement project was requested by the city of Lakewood.
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Update of projects underway
Crews are replacing the deck of the US 97 Biggs Rapids Bridge in Klickitat County. |
US 97 Biggs Bridge - Crews working on the
US 97, Biggs Bridge deck replacement project have completed concrete work on the Washington span of the bridge. Crews are currently pouring concrete on the truss span and will have it complete in preparation for reopening of the bridge, scheduled for May 23. The completion of the Washington span, roughly half the bridge’s length, represents an important milestone. The project is on time and on-budget and WSDOT looks forward to reopening the bridge for the summer harvest and tourist season. The second complete closure of the bridge begins September 2, when crews will complete the deck replacement and improve the bridge rails, illumination, drainage and striping. The project is expected to be complete by the winter of 2008 – 2009.
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Announcements
State Patrol: no double-crossing in SR 167 HOT Lanes;
Crews begin installing double striping, access zones this week
Crews began applying the solid double white stripes on SR 167 separating HOT (high occupancy toll) lanes from the general purpose lanes on April 12. Washington State Patrol troopers warn drivers that crossing the double solid lines could mean a citation and a fine as soon as the new HOT lane striping appears along nine miles of State Route 167 between Auburn and Renton.
Crews will grind down striping in several areas to create a single dashed line indicating access zones where drivers can exit or enter the HOT lane. Drivers of all vehicles, including buses, vanpools, carpools and motorcycles, may exit and enter only in these quarter-mile-long zones. Once inside the HOT lane, motorists should watch for signs directing them to the access zones preceding their exit ramp to ensure they don’t miss their exit. Solo drivers also must enter the HOT lanes in the access zones and will pay an electronic toll without ever stopping.
To use the HOT lane, solo drivers must first open up a Good To Go! account and install a transponder on their windshield. Carpools of two or more, vanpools, buses and motorcycles can drive in the HOT lanes toll free, and do not need to carry a transponder. HOT lanes will open to toll-paying solo drivers on April 26. But the “no double-crossing” rule will be enforced as soon as the double-white stripes appear on SR 167 next week.
Wire theft continues in Pierce County
Recent wire thefts have forced WSDOT to power an electronic overhead sign on SR 16 with a gas generator until the wiring can be replaced. The electronic sign, called a variable messaging sign or VMS, is located over eastbound SR 16 near Center Street in Tacoma. These signs are used to inform motorists of Amber Alerts and advise drivers during traffic incidents. Several locations along SR 16 were targeted over the weekend, continuing this national crime epidemic that is costing taxpayers millions and reducing public safety.
Statewide losses from wire theft since December 2006 are approaching a half-million dollars. So far this year in Pierce County, wire thieves have darkened lights and signals on I-5, SR 410, SR 512 and SR 161 – in areas stretching from Lakewood to Tacoma and Buckley to Puyallup.
WSDOT and the Washington State Patrol need the public’s assistance raising awareness of this type of crime. Motorists who have information regarding wire-theft along a state highway are encouraged to call 1-866-976-WIRE (9473). If drivers encounter a theft in progress, they should dial 9-1-1. For more information on wire-theft, please visit www.wsdot.wa.gov/maintenance/material/.
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Gray Notebook Highlight - Guardrail and Bridge Rail Upgrades
WSDOT continues to place an emphasis on improving roadside safety on state highways. The 2003 "Nickel" package set aside $20 million to replace guardrails built to now outdated safety standards. An additional $10 million was included for the strengthening of non-standard bridge rails. As of December 2007, WSDOT replaced 306,644 feet (58 miles) of non-standard guardrail barrier and 101,279 feet (19 miles) of bridge rail statewide. These upgrades reduce the risk of vehicles going through the rail and off the roadway. We expect to have the remaining guardrail projects completed by the end of 2009, and the remaining bridge rail projects finished by the summer of 2012. More details on this topic and other key issues can be found in the December 2007 Gray Notebook at: www.wsdot.wa.gov/accountability.
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April open houses, meetings, and events
15, 9 a.m. - 5 p.m., Local Meeting, Washington State Transportation Commission - Pullman: The Washington State Transportation Commission will meet with local officials to share information related to local, regional and state transportation issues. The public is invited at attend and may address the Commission during a public comment period, scheduled for 4:15 p.m. Location: Holiday Inn Express, 1190 SE Bishop Boulevard, Pullman.
22 Tuesday, 4 - 7 p.m., Open house, SR 14 Camas-Washougal Widening - Camas: WSDOT's project team will hold an open house to introduce design changes for the SR 14 widening project between Camas and Washougal. Location: Camas Police Department, Community Room, Camas.
22, Tuesday, 6:30 - 8 p.m., Public hearing, State Bicycle Facilities and Pedestrian Walkways Plan - Vancouver: WSDOT is holding a series of public hearings prior to finalizing an update of the state bicycle and pedestrian plan. Individuals are invited to hear a short presentation by WSDOT staff and provide comments about the plan. Location: WSDOT Southwest Region Office, 11018 NE 51st Circle, Vancouver.
For more details, please visit the WSDOT Calendar of Events.
Weekly Report Archive
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