Gary Hayes of Silver Lake writes: I have been hearing more about people driving the wrong way on our highways. It made me think about the one-way spike strips that you used to see at the exit of the drive-in movies. Why can’t those be installed part way down the off ramps to prevent wrong way traffic from entering the freeway?

Personally, I think the price of a life is worth more than the cost of four new tires.

Bronlea Mishler, spokeswoman for the state Department of Transportation, writes: We’ve heard from several people who have suggested the use of spike strips to prevent wrong-way driving. It’s an idea that we’ve discussed and studied for a number of years — and we’ve found that tire spikes are not a workable solution for us.

Right now, a system doesn’t exist that can safely deflate tires at the higher speeds we see at on- and off-ramps. Commercially made tire-spike systems all have a maximum passage speed of 5 mph, whereas traffic will often travel 20-30 mph near the middle or end of our ramps during a ramp green light. Requiring drivers to enter and exit ramps at 5 mph would likely create serious congestion.

What’s more, tire spike systems don’t hold up well long term, especially in areas with high traffic volume, such as ramps. Test results show that the hardware, springs, and “teeth” can break and fail — which is not something we want to have near freeway ramps. If for instance, a broken tooth remains exposed or if the system didn’t fold down completely, then even traffic headed the correct direction on the ramp could suffer tire damage. There’s also no guarantee that a wrong-way tire spike system could operate reliably in all snow and ice conditions.

Even drivers headed in the correct direction could be nervous about driving over a spike system. In-road spikes could appear intimidating and could lead some drivers to come to a panic stop or perhaps reflexively evade the spikes by turning into guardrail or a roadside ditch. And for drivers who do exit or enter a ramp in the wrong direction and have their tires deflated (by design), we’re not sure where they would actually end up; their vehicle could be abandoned or wind up in an unsafe location.

With all this in mind, we’ve had to use other methods to alert drivers that they are entering a ramp in the wrong direction. We currently use large, red signs displaying messages like: Do Not Enter, One Way, and Wrong Way. More recently, we have tried engineering ramps so that they are more challenging to access from the wrong direction. We engineer traffic curbs, islands and lane widths at freeway exits so that they interfere with or block drivers from turning the wrong way down a ramp. We’ve completed this work on about 20 highway interchanges where we’ve had wrong-way drivers, and we plan to expand this program.

Jordan Road bridge

Brandan Stafford of Granite Falls writes: I have a question about a bridge on Jordan Road between Granite Falls and Arlington.

On Jordan Creek Bridge near Jordan Bridge Park, the approaches to the bridge have been sinking over for the past couple of years, especially on the west side. Crews have been putting pavement on it every time it sinks and now it’s sunk so far down it causes a big bump. It’s so bad now you can’t even drive safely over the bump at 35 mph. I’m worried that one day someone will hit that bump hard enough to bounce them into the other lane and hit an oncoming car.

The bridge deck looks like it needs repairs, too. What is causing the approaches to the bridge to sink? What is the county doing about it to fix it and is there a plan to replace the bridge in the future?

County engineer Owen Carter responds: The bridge that Mr. Stafford is asking about is county bridge No. 214 over Jordan Creek.

Repairs are being designed and scheduled to be made this coming spring and summer. There is currently no plan to replace the bridge at this time.

The county uses the state Department of Transportation bridge rating system to rate all of its publicly owned bridges in the unincorporated parts of the county.

The bridge rating system uses several factors in determining a “sufficiency rating” for the bridge; one of the key factors is structural deficiency — in other words, does the bridge have components that are deteriorating? Bridge No. 214 currently has a sufficiency rating of 65 out of a possible 100. As of 2011, only bridges with sufficiency ratings of 40 or below are qualified for federal bridge replacement funds.

This bridge was originally built in 1981 with a timber deck with an asphalt overlay and timber abutments. It has an average daily traffic count of 1,036, 10 percent of which are trucks. Under these conditions, the asphalt pavement is susceptible to cracks over time.

Our engineers believe that the settlement at the bridge approaches may be a result of inadequate drainage underneath the abutments. The bridge slopes down from north to south. Water tends to accumulate at the north end.

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