Dear Dr. Gridlock:

The repaving and restriping of sections of Interstate 66 outside the Capital Beltway are a big improvement. It raises some questions, however. Why do some segments, but not all, have the HOV lanes separated from the normal travel lanes by double solid lines, while the rest are separated by only broken lines, as they were previously?

These areas are generally around exits. If the double solid lines mean what they generally do — that is, you shouldn’t cross the lines to change lanes in these areas — why are they completely ignored by so many people, and why aren’t there “Do Not Cross Solid Lines” signs, as I have seen in other places where solid lines separate normal travel and HOV lanes, in these areas to remind drivers?

I also like that the Red X shoulder lanes are now colored red or brown, clearly indicating they are not normal travel lanes. But there are still some special people who drive the Red X lanes for miles without regard for the rules.

John Loxton, Clifton

DG: Motorists might recall from driver’s ed that they’re not supposed to cross double solid white lines; however, it wouldn’t hurt to have signs reminding them.

The signs are trailing behind the pavement markings, which have been on I-66 since summer, but the Virginia Department of Transportation says the signs are coming. In most cases, they will be installed in sets of two as drivers approach the segments of the left-side HOV lanes that are marked with double lines. The first sign in the set will say “Do not cross double white lines,” pretty much what Loxton suggested. The second will say “Stay in lane / next 1 mile.”

The reason the solid lines are in some segments, but not all, near the Beltway is to give drivers an opportunity to change lanes where VDOT considers that safe, says Randy Dittberner, VDOT’s regional traffic engineer.

The new lines, and the new red-clay color for the shoulders, were part of the VDOT repaving project along the 6.5 miles between the Beltway and Route 50 in Fairfax County.

Safer crossings

Dr. Gridlock:

I have been using the Matthew Henson Trail crossing of Veirs Mill Road and think its engineering helps address the problem of drivers suddenly stopping for a bike at a crosswalk.

The crossing has sections of pavement on either side and in the median that are about 10 yards long and run parallel to the road. I can stop a few feet short of the crosswalk facing oncoming traffic, which seems to clarify to drivers that I am waiting for an opening before crossing.

One can activate a flashing stoplight at this crossing, but I rarely do this, because I am usually riding on weekends or other off-peak times and have to wait only a short time for a break in traffic. The parallel sections allow a cyclist to be on the bike pedaling in the crosswalk and across the road quickly.

It’s an improvement, but not foolproof. On one occasion, a driver stopped suddenly, causing locked brakes, tire smoke and swerving. I think if you go through the trouble of installing lights on a crosswalk, it would be better to use good old red, yellow and green rather than the various flashing arrangements that many drivers rarely encounter. A green light might have minimized this driver’s uncertainty.

Paul Wambach, Rockville

DG: In discussions about the safety of drivers, pedestrians and cyclists at trail crossings, we’ve talked mostly about the behavioral aspects. What should each party do to keep the other safe while not creating a danger with an unexpected move?

Wambach highlights some traffic engineering designed to modify behavior and better control the travel environment. Efforts such as this to enhance safety at crossings are underway across the region, but I wish we could see more of them.

There’s no cookie-cutter solution for all situations, particularly those in which walkers and bikers must cross multi-lane roadways such as Veirs Mill Road, one of several major crossings on the 4.2-mile Henson Trail in Montgomery County.

Safety experts tell me that a traditional green, yellow and red signal isn’t necessarily an upgrade on heavily traveled routes. They would rather go with a signal that remains dark unless activated by a person.

Have you seen such un­or­tho­dox designs for crossings in your communities?