Dear Dr. Gridlock:

In response to Karen Burcham, "Green Light for Hybrids" [Dr. Gridlock, Jan. 30], I have to wonder why, if she is so worried about the environment, she doesn't bother to pick up slugs or carpool to even further lower the amount of pollution?

I firmly believe that hybrid vehicles are a great thing for the environment, but allowing hybrid drivers to drive one person to a car is not going to solve any long-term problems. That's why I'm glad that the HOV exception for clean-fuel vehicles is scheduled to expire sometime in the next couple of years.

We need to ask ourselves a simple question: What pollutes more, three people sharing a ride in a car that gets 25 miles per gallon, or three people each riding in their own hybrid getting 40 mpg? The answer to that should be pretty obvious.

Hybrid owners already receive a federal tax break and save by not having to pay as much for gas. This should be enough incentive to buy one.

I own a diesel car that gets 45 mpg, and the only perk I get is lower fuel costs. That was enough for me to buy it! Plus, I don't have to worry about what happens to all the old batteries that will need to be disposed of from the hybrids.

Why should these hybrid owners get special HOV exemptions when I don't? The answer to that is they shouldn't.

Brian Broadhead

Fairfax

Monorail Debate

Dear Dr. Gridlock:

Your column Jan. 19 asked for someone to tell you why an elevated monorail isn't quieter, cheaper and more efficient transportation than widening roads or expanding Metro. Having recently come back to the East Coast from Seattle, I can only say that I believe our current Metro system, with needed improvements and extensions, would probably cost the same or less than building a new monorail system here.

Mr. [Bill] Cook's suggestion that we need a monorail to "string together" with our already existing system would be terribly costly. The monorail is not quiet, and the bond levy recently passed in Seattle to extend the monorail downtown through Seattle as well as other neighborhoods will tear up neighborhoods and already existing businesses, increase the car tax as well as other taxes, and establish a Monorail Authority paying high salaries to its administrators.

In fact, the new extended monorail doesn't go outside the city, is not underground, and will not serve all neighborhoods, yet alone transport folks to the airport.

I would suggest that Mr. Cook check out the price tag for Seattle's extended monorail against the cost of extending our Metro system linked with an already existing bus system.

Seattle has no rail system, and even though an initiative was passed in 1996 to build light rail, the project cost has far exceeded the amount of money approved and is being challenged, with no money coming from the feds. I guess the saying that "if it ain't broke, don't fix it" applies here.

But I would like to know how much it would cost to build a monorail here compared with Metro improvements and extensions.

Annabelle Fisher

Alexandria

Me, too. Metrorail extensions now are so expensive that desired ones may never be built.

The cost to extend Metro from the Falls Church stations to Dulles International Airport and into Loudoun County is about $4 billion. The federal government has bowed out, and with the financial crisis in Virginia, it's hard to see how that route will be built.

Has anybody got an estimate to build monorail?

Dear Dr. Gridlock:

Some points to consider:

Monorail probably would work better than road expansion if it were well implemented. Particularly if it went where people want to go.

The trouble is that the politicians and professional planners who have kept Tysons Corner, Georgetown and other such places rail-free would probably be involved with monorail. I don't trust them to do the job competently.

On the other hand, they haven't done too great a job with roads or Metrorail either, so this is probably a wash.

As to the comparison between Metro and monorail: If you point your Web browser at a search engine you'll find a lot of information about these systems with plenty of bias on both sides. It does seem, though, that the benefits of monorail (mostly projected because it's surprising how little monorail actually exists) are probably grossly overstated.

Finally, I'm wondering about the specific advantages you see in monorail. Why should it be cleaner or quieter than Metrorail and how much use would be made of the land underneath its right of way?

Whatever the form, I'm convinced that if a city cares about its future, an excellent public transit system with dedicated right of way is the best investment it can make.

Giles Morris

Arlington

Dear Dr. Gridlock:

In your column, you asked for "somebody to tell [you] 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 does not operate well or cheaply. The Seattle monorail costs a dollar per passenger mile, when Metrorail here costs only 35 cents. BART in San Francisco costs only 29 cents per passenger mile.

Monorail is also less safe than Metrorail, which has about 0.75 injuries per million passenger miles, whereas monorail suffers about twice that many.

In slippery weather, the rubber tires may slide unless the guideway is heated, which is prohibitively costly. Monorail will not be quiet unless the tires are bald, without tread. I am sure you would not approve that.

Both Seattle monorail trains have smashed up. Last fall, a train was disabled and the fire department had to evacuate the passengers by hook and ladder, a frightful experience from so high up.

Monorail needs just as much room as Metrorail for the same number of passengers. The guideway is narrower, but the safety catwalks require just as much space as Metrorail. Disney does not provide large cars or catwalks.

E.L. Tennyson

Vienna

Thanks for the details. I would not like to be in a position to have to be rescued by a hook-and-ladder truck. Still, I'd like to hear of any cost comparisons.

Honk if You're Mad

Dear Dr. Gridlock:

HOV violators, shoulder drivers, red-light runners, jaywalkers, all of them are getting on my nerves more every day. I go back and forth on whether to honk at them or not. What do you and your readers think? What if we all started honking at these folks to let them know we don't like it?

I hate to contribute to road rage or noise pollution. But these scofflaws need some attention, and they are not getting it from the law. I am talking about the blatant offenders who have no regard for conventional road rules.

What if, when a person drives down the shoulder to get to the off-ramp a half-mile ahead, 10 cars sitting in traffic honk at him in disapproval? Would they get the message? Would it change some behaviors?

Matt Allan

Annapolis

I don't favor honking to make a point because that can trigger a road rage incident, like when you are parked at a red light and the driver you have honked at gets out and heads toward you. What do you folks think?

Don't Blame Builders

Dear Dr. Gridlock:

Your railing against developers for causing the problems of traffic congestion and urban sprawl is silly. Every year, 1.3 million legal and about 800,000 illegal immigrants arrive in the United States, despite the wishes of an overwhelming majority of Americans.

That 2.1 million total is like adding 3 1/2 Washingtons every year. All those immigrants have to live somewhere. Blaming developers for housing them is like blaming farmers for feeding them.

Dan Rabil

Washington

Where did you get the idea I support expanded housing for illegal immigrants? My sense is that most new subdivisions in this area offer housing at $250,000-plus and are usually sold to affluent residents.

As a matter of fact, I oppose free education, health care, housing, automatic citizenship conferred to newborns, full voting rights, easy access to driver's licenses and bank accounts that are offered to illegal immigrants and are a big part of the attraction to come here.

Danger: Parking Lot

Dear Dr. Gridlock:

It is my contention that the most dangerous place to drive is not any of the roads or highways in the area, but in the parking lot of a supermarket.

For almost all the drivers in these areas, the rules of the road appear to be tossed aside, starting with those drivers who seem to think that the lanes are speedways at the Indy 500 as they hurtle toward any parking space nearest the door to the supermarket, ignoring pedestrians and other cars backing out of parking spaces.

Then there are the drivers of SUVs talking on their cell phones as they drive down the center of the lane, expecting everyone else to move out of their way.

My car has been in the body repair shop countless times from these careless, selfish drivers and has more dents than the moon has craters. Although I have no idea just how this situation can be corrected, perhaps this letter will alert the driving offenders to the very dangerous game they play with the lives and property of others.

Eugene D. Markowski

Washington

One thing we can do is park in the spot farthest from the front door. Less dent potential and good exercise.

Transportation researcher Diane Mattingly contributed to this column.

Dr. Gridlock appears Sunday in the Metro section and Thursday in Fairfax 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.