SR 28 - Rock Island Slope Stabilization
click to view a larger map. This slope stabilization project is located above SR 28 between mileposts 11.01 and 12.1, near Rock Island Dam, in Douglas County.
Click to view larger photos
Excavation of the Rock Slope began on April 1, 2003.
Progress of the excavation as of August 13, 2003.
||220,000 cubic yards of basalt rock - 18,000 dump truck loads - were removed from the slope in stage 1.
||Work had to be suspended between November and April due to wintering bald eagles.
||The project was designed to accommodate future widening of SR 28.
Stage 1 - Completed
Work began on April 1st, 2003 and was finished on August 28, 2003. It was completed on schedule and under budget.
Why did WSDOT
do this project?
The primary purpose was safety. This phase of the project addressed an unstable 300-foot high basalt rock slope to stop rocks from falling onto the highway. At the same time, the project was also designed to accommodate future widening of SR 28.
How long did it take?
The contract was awarded to Scarsella Brothers Inc. of Seattle. The contractor worked on access roads and site preparation until November 1, 2002. Work was then shut down until spring due to wintering Bald Eagles in this area. Work got underway again on April 1, 2003 and was completed on August 28, 2003.
How was the work accomplished?
Controlled blasts were used to loosen the 220,000 cubic yards of basalt rock (approximately 18,000 dump truck loads) that was removed from the site. Two to three controlled blasts per week were necessary to excavate the rock. The blasts had to be scheduled around AMTRAK and Burlington Northern Sante Fe train traffic. Huge off road dump trucks were used to haul the rock to a state furnished stockpile site just south of the work site. This material will be used for future WSDOT projects.
What were the traffic impacts?
Blasting required the complete closure of SR 28. All of the blasts took place around 5:45 a.m., allowing the contractor 45-minutes to reopen the highway. There were two instances when more rock than was expected ended up on the roadway and the highway and the closure exceeded 45 minutes. The contractor was fined both times. After the blasts, traffic delays were limited to 20 minutes. Due to very heavy traffic volumes on a few occasions, the non-blast delays exceeded 20 minutes. Whenever that happened, the contractor cut work operations to reduce the delays. After the project began, WSDOT incorporated a traffic control monitor to reduce the delays.
The End Result
Slope stabilization through this mile long section reduces the danger of rocks falling onto the roadway and also onto the railroad tracks below the highway.
While reducing the risk of rocks falling onto the highway, the project also provides for two more future lanes when SR 28 is widened to four lanes.
What was the project timeline?
This was the first of three-stages of the project.
Stage 2 constructed a soil nail retaining wall 300 feet above the roadway. Construction began in April 2004 and was in late fall 2004. The wall retains loose rock from the talus slopes above it.
Stage 3 involves redirection and containment of rock fall by installing slope netting short distance north (upstream) from Stage 1. Stage 3 is currently in the design phase.
Your questions and concerns are important to us. Please contact Bob Romine at the Project Engineering office listed at the bottom of the page.
Work was shut down on this project between November 1st and April 1st due to wintering Bald Eagles in this area.
Please visit the WSDOT Environmental
Services Web site for more information.
Increasing safety is a priority
An elaborate public notification plan was implemented to keep travelers safe during this project.
Since there were no reasonable detours available to get around the work zone, WSDOT was committed to giving the public as much notice about expected closures and delays as possible. The following were some of the methods that were used:
This web page.
A traffic camera image on the web page that showed the work area and highway traffic conditions that updated every few minutes.
Portable Highway Advisory Radios (frequency AM 530) were placed at the intersection of SR 28 and Grant Road in East Wenatchee and also just west of Quincy with frequent updates on blast schedules and traffic delays.
E-mail and faxes for media, businesses, schools and emergency services alerted users of the planned work and traffic controls for the next 24 and 48 hours.
Electronic changeable message signs were used to inform travelers of current and upcoming traffic impacts.
WSDOT worked closely with local radio stations and newspapers to constantly inform the public of current and upcoming delays and closures.
Did this project impact tribal resources?
WSDOT seeks to address the concerns of tribal nations using the process outlined in Section 106 of The National Historic Preservation Act and the WSDOT Tribal Consultation Policy adopted in 2003 by the Transportation Commission as part of the WSDOT Centennial Accord Plan.
No tribal lands were affected by this project.
Stage 1 of this project was funded through the following source:
Stage 1 of this project came in $19,203 under budget.
How can I get more information?
WSDOT North Central Region
P.O. Box 98
Wenatchee, WA 98807
Phone: (509) 667-2880 or toll free (888) 461-8816
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