Dear Dr. Gridlock:

I cannot believe (actually, I can) the hypocrisy of people like Jim Woods [Dr. Gridlock, Jan. 12]. He's decided that his left-lane, illegal speed of 6-7 mph over the speed limit is okay, but not 10 mph.

Who gets to decide what illegal speed is okay? Obviously, Mr. Woods believes he can. If only we would observe passing lane courtesy like the Europeans.

In all my road trips in Europe, I've never observed anyone, at any speed, blocking the passing lane. As a result, I've never experienced anyone tailgating me as I used the passing lane to pass (a common occurrence in this country).

They obviously assume that when I'm done passing, I'll move out of the passing lane. But as long as we have people like Mr. Woods, we'll never be able to experience that kind of driving in this country.

Errol R. Waits

Arlington

Think of Your Elders

Dear Dr. Gridlock:

I suspect that the people who want bench seats on Metro are relatively young and in good health. But reducing the number of seats in a car to increase standing capacity will only mean that senior citizens and others for whom standing is difficult (e.g., with a bad knee or back) will have even less chance of finding a seat.

Metro should serve all customers and not just the physically fit. Unfortunately, we all know that senior citizens cannot always rely on the kindness of strangers to get a seat.

Carolyn Fields

Arlington

Where Pedestrians Rule

Dear Dr. Gridlock:

I attended law school in San Diego, and things are truly different there. One Sunday, just before my school semester started, I was in downtown San Diego. The area was deserted, and I started to step off the curb in the middle of the block (I'm from this area, hence the bad habit) when I suddenly noticed a police car about a half block away.

The officer was watching me intently. I stepped back and went to the crosswalk. Only then did he pull away.

Erin Gilland Roby

Ellicott City

I've heard that California is much more stringent about protecting pedestrians, hence pedestrians feel safer stepping into a crosswalk. Here, we've got chaos in the crosswalks and too many fatalities.

Monorail Debate

Dear Dr. Gridlock:

You ask: "Somebody needs to tell me why an elevated monorail system -- clean, quiet, taking up little room -- wouldn't work better and less expensively than either road expansion or more Metrorail."

Monorail has no track record as a serious part of transportation infrastructure. The projects in Las Vegas and Seattle will be interesting test cases, but I'm not optimistic.

It's probably a good fit in Vegas, in which the glitzy, futuristic look is as important as anything else.

Monorail is really only appropriate for short-distance, limited-stop, tourist or airport applications. It does not scale well to large passenger volumes.

Switching is much more involved than with traditional rail lines: The entire concrete guide beams need to be swung, using hydraulic jacks.

So a system where two lines share the same track for part of the run, the way the Blue and Orange lines do for example, becomes impractical.

Some detailed analyses of monorail projects are at www.lightrailnow.org/facts/fa_monorail.htm.

Tom Metcalf

Washington

Dear Dr. Gridlock:

A monorail has a few difficulties compared with other transit systems, especially in this area.

First is safety and security. To a terrorist, I would imagine a monorail is a preferable target. A monorail support piling would potentially seem to be much easier to take down with explosives than a solid rail bed or a (presumably highly reinforced) tunnel.

And each piling would be a target, as opposed to the intermittent bridges and overpasses that exist now (e.g., on the Red Line between Union Station and Brookland, Silver Spring station, National Airport and the Beltway crossing south of Grosvenor), making it much harder to police and secure.

Second, monorails in some instances have difficulties with evacuation in a malfunction. In Seattle, the monorail is being specially designed so city firetrucks' ladders can reach the car doors in an emergency. This may work well in a fully urbanized context, but for the Virginia railroad right of ways, I suspect a full access road might be required, upping the land cost.

Third, monorail has technical issues dealing with some geographic features. For example, a crossing in the upper Potomac valley (at the American Legion Bridge or in the area of the proposed "techway") would need to span a long chasm.

Finally, monorail has problems associated with switching tracks that are not present when dealing with normal surface or subsurface metal rails.

Don't get me wrong. Monorail has some distinct advantages, especially in terms of cost and disruption in the normal street grid (as we find, say, with Eisenhower Avenue and the Beltway). But we should not look at it as a panacea.

Andrew Perlmutter

Washington

Neither should we dismiss it. If it is so impractical, why are the Japanese and officials in Seattle and Las Vegas endorsing it?

Consider this: When widening an interstate highway, one of the big costs is demolishing existing overpasses and constructing new ones for the wider road. Instead of all that cost, why not build a monorail up and over the existing bridges?

I appreciate your thoughts. I'm not ready to give up yet. Please read on.

Dear Dr. Gridlock:

I think I'm missing something. . . . With all the arguing over new Metro, light rail and bus rapid transit lines, why hasn't anyone mentioned elevated rail?

The Miami Metrorail has been operating since 1985; check out www.co.miami-dade.fl.us/transit/metrorail/info.htm.

It parallels gridlocked Route 1 and Interstate 95; serves historic neighborhoods, university campuses, pro sports facilities, the downtown government and business centers, urban neighborhoods, commuter suburbs, shopping malls; and it crosses the busy shipping lane of the Miami River.

All on conventional tracks, but without a single tunnel, road crossing, extra road lane, special bridge, major environmental impact or large property buyout.

It's built to withstand hurricanes, which it easily did when Andrew destroyed entire neighborhoods in 1992.

The original cost in 1985 was $1 billion, about $50 million per mile. The projected cost for Metro to Dulles is four times higher, before the inevitable huge cost overruns. Yeah, I gotta be missing something.

Alan Marsilio

Manassas

There's a Cheaper Way

Dear Dr. Gridlock:

I heard on the radio yesterday that the Virginia Department of Transportation just installed some newfangled "acoustic sensor" contraption at the on-ramp to Interstate 495 from Route 236 to help prevent tractor-trailers from rolling over on the sharp curve at dangerous speeds. The cost? Just a mere $500,000 for one intersection.

Was the metal signage company out of business? What is wrong with the simple yellow "Truck Rollover Area, Slow Down!" sign like those placed at the I-495 on-ramps from Interstate 95 north? Those probably cost about $20 and certainly are not anywhere near $500,000.

This great high-tech solution we have now senses the truck's weight and speed and flashes the exact same warning message.

Virginia leaders wonder why the voters would not approve a tax hike for transportation use? I'd say this is the case in point of why taxpayers do not trust them to use the money wisely. Awful.

Kyle W. Thompson

Leesburg

Well, I voted for the sales tax increase, but I certainly take your point. Add to this the backward installation of an expensive electronic sign on Route 29 in Prince William County, plus the wild cost overruns for the Springfield interchange, and you can see why some residents don't trust the people responsible for local transportation improvements.

For Goodness' Sake

Dear Dr. Gridlock:

As a good Samaritan, I find it curious to think people think we do it for money.

In my years of helping others, I have never asked for, neither would I ever accept, payment for coming to the aid of someone.

I have changed tires, provided jump-starts for dead batteries, hauled folks to service stations to get a can of gas for their empty tank and even pulled the unfortunate out of wrecked vehicles.

I have stayed with accident victims while waiting for an ambulance, not so much for my medical experience but to offer the comfort of one person to another.

To render assistance to the less fortunate, whether it is on the road or the highway of life, offers its own reward: to help another human being!

If you have been the recipient of roadside or parking lot assistance, my advice to you is: Pass it on!

Howard Walker

Catlett

Thank you, Mr. Walker. We need more like you.

Speed Up on HOV

Dear Dr. Gridlock:

I am interested in hearing your thoughts on HOV drivers who drive slower than traffic in the conventional lanes.

I know that HOV is not meant as a speedway, but it seems counter to the purpose of HOV, which is to reward drivers who carpool with faster commute times, to have drivers in the HOV lane who are driving the same speed or slower than the traffic in the non-HOV lanes.

My husband and I have been stuck behind such drivers in the HOV lanes on Interstate 66 East many times and find it very frustrating as we are going even slower than the non-HOV lanes at certain points on I-66.

Lynn Pina

Gainesville

Slower drivers should move right, even out of the HOV lanes, if a vehicle is trying to overtake them. Signal that intent with flashing lights or honking. By Virginia law, the slower vehicle must pull to the right.

If the slower vehicle will not budge, you'd be justified in passing him on the right and getting right back into the HOV lanes.

With these kind of obstacles and number of violators, I'm beginning to wonder whether the HOV lanes are a failure. Are they?

Transportation researcher Diane Mattingly contributed to this column.

Dr. Gridlock appears Sunday in the Metro section and Thursday in Alexandria Arlington 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.