By Bill Sheets Herald Writer
William Landert of Marysville writes: Why is it necessary to have dedicated right-hand exit lanes on the freeway? These lanes are a real pain.
Any lane change increases the chances for a collision, especially when you have those jerks who absolutely refuse to give you room to move over.
Bronlea Mishler, a spokeswoman for the state Department of Transportation, responds: Explaining why we have those right-hand exit-only lanes on the freeways can get complex. The short version is that those lanes help the freeway transition from more lanes to fewer lanes, and help eliminate some areas of merging traffic.
The longer version goes something like this: Freeways are designed with enough lanes to serve the amount of traffic in the area. Some areas have more traffic than other areas, so they have more lanes. For example, I-5 in the Bellingham area is two lanes while much of the Seattle area is four or five lanes. For freeways to transition back and forth from urban areas (with more lanes) to rural areas (with fewer lanes), sometimes a lane becomes an exit-only or “drop” lane.
There are other reasons for drop lanes, too. Some freeway interchanges handle a lot of traffic, so to minimize the amount of merging drivers have to do, a lane is added to the freeway. Similarly, at interchanges where a lot of vehicles are exiting, the extra lane ends after the exit. Lanes can also drop off before physical barriers like bridges or in areas where we have limited right of way.
Drivers need to pay extra attention to traffic any time they’re merging or changing lanes. For exit lanes, we typically have signs placed at least a mile prior to the exit to give drivers ample time to change lanes. Signs for exit-only lanes also have a yellow “Exit Only” strip across the bottom of the sign.
Stop sign safety
Kellie Cooper of Lynnwood writes: Why did the county install a stop sign on Meadow Road near 137th Street SW near south Everett a few years ago?
It really doesn’t make sense to have a stop sign in the middle of an arterial when you are only stopping for light traffic coming from a side street.
Owen Carter, chief engineer for Snohomish County, responds: The county became aware of restricted sight distance at the intersection 137th Street SW and Meadow Road. A preliminary engineering study estimated the cost to re-grade the intersection and correct the sight distance problem at more than $2 million.
It was determined that installing stop signs to make the intersection operate as an all-way stop would correct the safety issue while the county pursues funding to make the permanent correction.
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