King County Road Services Division crews stay on top of small slides to help keep them from becoming bigger problems.
| Road Division digs into ‘shoulder season’In the travel industry, “shoulder season” is the time between high demand and the off season when vacation bargains can often be found. The King County Road Services Division experiences its own "shoulder season," but in a very different way.
For the Roads Division, the shoulder season occurs in the winter after heavy rains cause slopes and hillsides to slide or move, piling mud and debris on the road shoulder. Or, it is when the road shoulders are undermined by erosion. The shoulder season can keep road employees traveling across the King County unincorporated areas for incidents large and small. They are responding to known slides, but also working preventively looking for the telltale sign of oozing, wet mud across the road shoulder, oftentimes with trees or limbs attached. Sometimes, it’s just a pickup truck full of debris that needs to be cleaned up and hauled away, but some jobs require several dump trucks. Besides the obvious – cleaning up the material with a front loader or excavator – there are a couple of other tactics that help stabilize the slopes and shoulders. Vegetation plays a big part. If the slope is bare after a slide, Road staff will consider hand or hydro seeding the area. The seed mix, which can be grass, wildflowers, or a mix of both, contains plant nutrients that sort of glue it to the affected area. Once the shoulder season transitions to spring, a visual inspection will reveal the extent to which the seeding worked. Vegetation has another advantage in that it can help water quality. Rainwater running over vegetation is usually cleaner than when it runs over exposed dirt. Dirt can cause turbidity in the water, which affects fish and other wildlife. These plantings are sometimes aided by textile or geo-textile fabrics. Some fabrics keep water away from an area, some allow the water to drain quickly, and some allow it drain slowly. In the last 20 years, there has been a huge development in this are. Dozens of different types of long-lasting fabrics are now used for these stabilization projects.
On Vashon Island, a timber crib wall was built to stabilize this hillside many years ago. And, with proper maintenance, it still does the job.
| Another common fix is the installation of retaining walls. These can be as simple as a rock or block wall or a more complex engineered system using pin piles. Gabions, rock-filled baskets, have been around for decades. Cribbing, which resembles walls built with large-scale Lincoln Logs, is also used to reinforce steep slopes. Two examples of these are the concrete crib wall along Juanita-Woodinville Way and a log retaining wall near Bunker Trail on Vashon Island.Sometimes the slope itself isn't the issue. Water from springs or other sources can cause drainage problems. Installation of pipe that gathers the water from the wet slope and more complicated horizontal drains are used in these instances. There are diagnostic tools that can track whether slopes are moving. Instruments called inclinometers and piezometers are sometimes installed to track the amount of slope movement.
In spite of the many tools that can be used to contain slides, weather has a way of altering the best-laid plans. That is why road crews are always on alert for signs of trouble, and invite the public to call (206) 296-8100 or 1-800 KC ROADS if they notice potential slides or shoulder problems in their unincorporated-area neighborhood.
Standard adult ORCA cards can be purchased at any Link light rail ticket vending machine.
| ORCA smart cards, which are gaining popularity among Puget Sound transit riders, will now be available with no fee through Feb. 28. Starting March 1, 2010 a standard adult or youth ORCA card will cost $5. The promotion had been scheduled to end on Jan. 31. The “blank” ORCA cards available with no fee through February must be loaded with e-purse value and/or passes. The extended no-fee promotion should help ease the transition to ORCA and reduce temporary high volumes of activity at customer service centers. Each of the ORCA partner agencies has been taking additional special measures to meet the high demand. Riders who use a Regional Reduced Fare Permit (RRFP) are reminded that there is no charge for converting to the ORCA card. The best time to obtain an ORCA RRFP card at customer service offices is between the 10th and 20th of each month. First-time RRFP customers who qualify for the reduced fare must still pay an initial fee of $3.
Given the heightened interest in converting to ORCA, Metro Transit’s Seattle sales offices on the mezzanine level of Westlake Tunnel Station and at King Street Center, 201 S. Jackson St., will be open Saturdays beginning Jan. 30 and continuing through the end of February.
The Seattle Department of Transportation (SDOT) is beginning the next phase of widening the South Spokane Street Viaduct on Jan. 22. This phase should have minimal disruptions for King County Metro Transit customers. As SDOT begins renovations on the 60-year-old elevated roadway that connects Interstate 5 to the West Seattle Bridge, there could be increased traffic congestion which could delay bus travel – but no transit reroutes will be necessary at this time. In May, when SDOT permanently closes the westbound South Spokane Street Viaduct on-ramp to the West Seattle Bridge from First Avenue South, there may be a reroute near that on-ramp for buses traveling between the SODO area and West Seattle. Information about that will be available this spring on Metro Online. For more information about the Spokane Street work, please visit the project website.
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