Traffic clogs I-95’s regular lanes and express lanes in the Quantico area at the start of the Memorial Day weekend. (Win McNamee/Getty Images)

Dear Dr. Gridlock:

Is Virginia doing anything to improve traffic flow on Interstate 95 between the Capital Beltway and Fredericksburg? I’ve driven to Fredericksburg and back two or three times a month for over 20 years, and since the express lanes opened, it’s been worse than ever.

You would expect that in the middle of the day there wouldn’t be a problem, but on a recent Friday, I left my house in Potomac before 1 p.m. and didn’t get to Fredericksburg until after 3. I used to do it in one hour.

Seeing that I-95 is the main highway on the East Coast, Virginia should have added two lanes to the main line in addition to the express lanes. Where the express lanes end, there is always a two- or three-mile backup as the two lanes turn into just one.

I can assume that people paying to use the express lanes must be frustrated about that. That was the same problem on southbound I-270 entering the Beltway 20 years ago before they fixed it to let two lanes merge on the Beltway. Virginia should do the same.

— Ati Kovi, Potomac

As drivers prepare to start their engines for the Labor Day weekend getaway, they need to know that the summer-long slowdown continues at the point where I-95’s regular southbound lanes and the 95 Express Lanes merge, just north of Garrisonville Road in Stafford County.

The Virginia Department of Transportation is aware of the congestion that extends for at least a few miles in both the regular and express lanes and is trying to figure out what to do about it. But no plan has been announced.

This is one place where Virginia’s HOT (high-occupancy toll) lanes are not working. The variable toll does, indeed, shoot up, just as the dynamic-tolling theory says it should. That’s supposed to discourage drivers from entering the lanes, but it doesn’t relieve the slowdown, which is a function of the merge of the two express lanes with the three regular lanes.

A good long-range plan would be to extend the express lanes south to where early, more ambitious plans would have put the terminus: Massaponax, near Fredericksburg. A shorter-range solution would be to extend the merging area.

That would help, but it wouldn’t be a fix, because the lane reduction still would occur within a high-volume area on the interstate.

Meanwhile, if you’re planning a holiday drive in the toll lanes on Friday afternoon or on Saturday morning, watch for signs warning of a slowdown ahead and consider returning to the regular lanes via the exit for Quantico/Joplin Road.

By the way, I think that I-270 merge with the Beltway needs a fresh look to deal with morning congestion, and it’s very unlikely the solution would be limited to more highway widening. Maryland needs to look at ride-sharing solutions — carpools and commuter buses — just as Virginia is doing.

Driving HOT

Dear Dr. Gridlock:

Philosophically, I believe in HOT lanes — paying for what you use — but I am critical of their implementation.

On the way home from Maine this summer, we encountered the HOT lanes on I-95 north of Baltimore. The left lane led right into toll lanes with no warning that they were tolled. My wife was into the toll lanes before she realized it. We do not know what the cost was, but whatever it was was a waste, as there was little traffic in the regular lanes, which were actually moving a bit faster than the HOT lanes.

In my opinion, the Virginia HOT lanes at least give you fair warning.

But so far, the Virginia HOT lanes have not been worth the toll, in the times I have encountered them.

I see no point in using toll lanes if the regular lanes are moving as well, and even when they are not, $10 or more is more than they have ever been worth to me. If the southbound HOT lanes flowed at the speed limit all the way, including at their end, I might feel differently, but they don’t. And I hesitate to take toll lanes when the price all the way to their end is not posted.

— Gordon White, Deltaville, Va.

A technical note: Maryland doesn’t have HOT lanes. Maryland’s express toll lanes north of Baltimore and across the D.C. suburbs on the Intercounty Connector provide a reliable trip in exchange for a toll but do not offer a free ride to high-occupancy vehicles, as do the Virginia express lanes.

One thing they have in common is that drivers lack an easy, immediate way of deciding whether the express ride will be worth the toll for the entire length of the trip.

If they haven’t checked traffic conditions via radio, TV or the Internet, they need to make their best guess based on experience.

Dr. Gridlock also appears Thursday in Local Living. Comments and questions are welcome and may be used in a column, along with the writer’s name and home community. Write Dr. Gridlock at The Washington Post, 1150 15th St. NW, Washington, D.C. 20071, or e-mail drgridlock@