Dear Dr. Gridlock:

On Jan. 25 I had the misfortune of having my car break down at the very heavily traveled intersection of Muncaster Mill and Airpark roads in Gaithersburg.

While I waited in the cold for a tow truck to arrive, numerous motorists stopped to ask if I needed a ride or would like to use their cell phones. I lost count of the number of people of who offered such assistance in the approximately one hour I was stranded.

My initial inclination when the first of these strangers stopped was that they were slowing to curse me for blocking a busy intersection. It is very comforting to know that there are so many courteous caring individuals out there.

I'll think twice before I pass a stranded motorist in the future.

Richard Barna

Potomac

That's it; pass the favor along.

Snow Woes

Dear Dr. Gridlock:

Since we have had a lot of snow this winter, I thought it would be appropriate to write about this. Many drivers, when cleaning the snow off their cars, neglect to clean the snow off the roof.

This can be very dangerous. When the snow is fresh and powdery, it tends to blow right off and act sort of like a "fog" to drivers around them. Often, when the snow stays on the roof for a few days, it turns into a sheet of ice that can break off of the roof and fly into nearby cars. This can block other drivers views, at least, and can even crack windshields.

In all cases, simply remembering to clear the snow off a vehicle's roof can make our roads safer.

Gary Bernstein

Chevy Chase

A Bigness Tax?

Dear Dr. Gridlock:

One of your readers proposed taxing SUV drivers, as he believes they add to congestion. I assume he is referring to the amount of road surface space an SUV consumes, which would be measured by length and width of the SUV.

To implement this idea, we would logically tax all SUVs and any vehicle that meets the same (or larger) length and width dimensions. After all, a van with the same footprint adds equally to the congestion problem.

Let's compare some 2003 models. The smallest SUV I could find is the Chevrolet Tracker. It is 151.8 inches long and 67.3 inches wide. That would be the benchmark for the proposed tax.

The following vehicles exceed at least one dimension of the Tracker: Ford Focus (178.2 x 67), Dodge Neon (174.3 x 67.4), Honda Civic (174.7 x 66.7), Chevrolet Cavalier (180.9 x 68.7) and Toyota Prius (169.6 x 66.7). In fact, the only car I found that did not exceed the dimensions of the smallest SUV was the Cooper Mini (142.8 x 66.5).

If your reader would like to tax all large vehicles (for example, those that meet or exceed 200 inches in length), he would have to include some SUVs (Ford Expedition 205.8 x 78.7), some trucks (Ford Ranger 202.9 x 70.4), some vans (Ford Windstar 200.9 x 76.6) and some cars (Ford Crown Victoria 212 x 78.2).

The idea that all SUVs are large and that only large vehicles are SUVs is ridiculous.

The reality, found on the official Web pages of automotive manufacturers, is far different.

If your reader would really like to encourage purchase of small vehicles to ease congestion, perhaps we could give a tax break to motorcycle owners.

Elena Falls

Germantown

Biking Works

Dear Dr. Gridlock:

I've just switched to biking to work -- it's cheaper, faster and great exercise for my 10-minute ride between my Capitol Hill home and my downtown office.

I'm astounded, though, at how few drivers know that cyclists have the right to be on the road. Not a day goes by when I'm not nearly sideswiped by a car passing too close or honked at by some driver shouting, "Get off the road!"

Could you take a moment to remind your friendly driving readers that cyclists are required to ride on the road in downtown D.C. and that we have the right to take up a full lane?

Julie Eisenhardt

Washington

You've just done so. Again, with prohibitive costs of new roads and rail, we need to do everything possible to encourage bicycle commuting.

Getting Even Is Dangerous

Dear Dr. Gridlock:

As a cautious driver with a mild temperament, I rarely get upset while driving. In recent weeks, however, I have become annoyed with drivers who come to the front of a line of cars that are waiting to merge into traffic.

Those drivers seem to feel that they should not have to wait their turn in line but should be permitted to merge at the front of the line.

This morning, as I approached the South Capitol Street Bridge from Howard Road, I remained in line but not completely in my lane -- thus blocking cars from passing me and proceeding to the front of the line. For at least one morning a few of those disrespectful drivers were not permitted to pass those of us in line and go to the front of the line.

Rufus Horton

Landover

I know it's frustrating, but I don't recommend blocking these rude drivers; we just don't know what ugly consequence might develop.

A little farther north, on the access to northbound D.C. 295 from eastbound Pennsylvania Avenue, two lanes merge into one. Large yellow signs, on the left and the right, announce: "Alternate Merge," and readers tell me it works. Drivers take turns merging. I'd like to see more such signs to bring more order to merges.

A Merge That Works

Dear Dr. Gridlock:

An "Alternate Merge" sign is in place on the entrance ramp from Dulaney Valley Road to the outer loop of the Baltimore Beltway (Interstate 695). That's on the north side of Baltimore, near Goucher College.

I've used the ramp in busy periods, but not at peak times, and it's surprising how well drivers take turns getting in line. The sign is a good reminder to "play nice."

Duncan Munro

Beltsville

D.C. Can Fine Md. Driver

Dear Dr. Gridlock:

I live in Maryland, and my car is registered in Maryland. I was recently cited and fined there for not having a front license plate (it got mangled in a parking incident). In the meantime, I'm awaiting two new plates.

Just the other day, D.C. parking enforcers also cited me for not having a front license plate. Do they have the jurisdiction to fine me for a Maryland infraction? I find the whole thing ridiculous.

Dean Schleicher

Owings

Sorry, they do. I've been told the D.C. Parking Control aides have a list of all the states that require only one license plate. Maryland isn't one of them, and they are empowered to write the ticket.

Give Monorails a Chance

Dear Dr. Gridlock:

Monorail systems deserve serious consideration from regional planners across the United States as a way of providing clean, efficient and cost-effective public transportation options.

For some reason, a bias toward expensive and disruptive light and heavy-rail construction continues to hold sway among transportation decision makers.

The monorail under construction in Las Vegas and the Seattle monorail expansion initiative should help to dispel the myth among Americans that monorails are just amusement park rides.

The Web site www.monorails.org (which I am not affiliated with) has very useful facts about monorail systems throughout the world, links to existing and planned projects, comparisons with other transit systems and cool photos, too.

Here is a brief summary of just a few monorail benefits:

* Safety. It's almost impossible for monorail trains to derail, and unlike some light rail systems, monorail systems operated on exclusive elevated guideways prevent accidents with other vehicles.

* Cost. Among other things, expensive tunneling (subway) and right-of-way grade preparations (surface light rail) are eliminated. Many of the concrete support elements can be formed off-site, then quickly installed. Surrounding businesses, homes and traffic are significantly less affected during monorail construction. Businesses can keep running, and customers can still access them. Additionally, many monorail systems actually turn a profit once constructed. See this link: www.monorails.org/tMspages/MonoVs.html.

* Environment/aesthetics. Besides being nonpolluting, Monorail systems are known for legendary quietness, something that parks and zoos have always known.

Monorail systems can easily traverse varied topography without requiring massive grading modifications. Track and station designs can be adapted to a variety of styles. Many systems in even have lush gardens, paths and trees beneath the guideways. See this link: www.monorails.org/tMspages/enviro.html.

In short, monorails aren't a joke or a toy. They're serious transportation systems that move millions of people every day, more safely and at less cost to taxpayers than other transit systems.

When appropriate, I hope that you can help make the public aware of these benefits in your column in the future.

Bill Cook

Alexandria

Thanks for the information. I remain interested in this form of transportation. There is nowhere near the financial support to extend Metro to Dulles International Airport (a cost of $4 billion). I'm wondering what monorail can be built for.

A postscript: One reader concern that resonates with me is how to get people out of disabled trains. I'm not keen on a hook-and-ladder rescue. Comments?

Transportation researcher Diane Mattingly contributed to this column.

Dr. Gridlock appears Sunday in the Metro section and Thursday in Montgomery Extra. You can write to Dr. Gridlock, 1150 15th St. NW, Washington, D.C. 20071. He prefers to receive e-mail, at drgridlock@washpost.com, or faxes, at 703-352-3908. Please include your full name, town, county and day and evening phone numbers. Dr. Gridlock cannot take phone calls.