One of the common complaints from readers is about how hard it is to see white lines in the road in this area. Many of them seem worn away, but the problem is particularly acute at night, in wet weather. "It's like driving on a mirror," writes Ann Ballantyne of Laurel. "On dark, rainy nights it is almost impossible to see the white or yellow painted lines that mark the lanes." It doesn't take a rocket scientist to figure out this is dangerous, particularly when you can't find lanes on a slippery, poorly lit interstate highway.

It's different in the West, of course. There, many highways are marked with highly reflective paint, and slightly raised discs are installed between the broken white lines. Reflectors are set in those discs, and the slight vibration and noise they provide when passing over them help alert drivers who begin to drift into other lanes.

Why should major roads be marked less efficiently here? Does the federal government give more money to road systems elsewhere? Do local officials elsewhere care more?

Maryland, Virginia and District road officials concede there is a problem here, and they say they are starting to do something about it.

Said Maryland's Mike Snyder: "We know when the water gets thick enough on a road -- and it doesn't have to be that thick -- that no matter how thick your paint is, we lose reflectivity and you can't see the lines any more."

The discs and other raised reflectors used in California and other states won't work here because the snowplows pop them off, area officials say. "And that's $5 a disc," Snyder said.

Local officials have been testing a new reflector that they say is far superior to the old methods used here. It is made of hard plastic, something like the reflector on the back of a bicycle, and is recessed into the pavement so that plows won't affect it. Test results have been good, Snyder said, and the state has allocated $250,000 to imbed these markers on 100 miles of Montgomery and Prince George's roads this year. When this is done, the Maryland Beltway will have the new markers, as well as Branch Avenue in Prince George's, I-95 toward Baltimore, and parts of Rte. 29 (Colesville Road) in Montgomery County. Currently those new markers are in place on the Beltway and I-95 for a short distance where those roads intersect.

I-270 in Montgomery County is not affected this year because of the heavy construction under way there to widen that artery by the early 1990s.

Virginia Highway Department spokeswoman Marianne Pastor says that state spent $1.75 million on the new, highly reflective recessed markers last year and will spend $1.5 million more in the fiscal year starting July 1. "We have identified the need for these markers and we are doing them on a priority basis," starting with the most heavily traveled roads, she said. Currently, there are new lane markers in the following locations: I-95 from Springfield to the Prince William-Stafford border; Rte. 7 from the Dulles Toll Road to Leesburg; Rte. 1 for five miles north of Backlick Road; Rte. 1 in Prince William County from Opitz Boulevard to Dumfries; Rte. 50 in Fairfax County to the Loudoun County Line, and Davis Ford Road in Prince William from Bent Tree Lane to Occoquan Forest Road.

Local Virginia contracts for this year include Rte. 123 from Burke Center Parkway to the Prince William County line; Rte. 15 from the Prince William County line to Leesburg; Rte. 234 from Manassas to Rte. 1 and I-95 from Springfield to the Wilson Bridge. The Shirley Highway, the most heavily traveled road in Virginia, is not considered a top priority because it is lighted, Pastor said.

In the District, chief traffic engineer George Shoene said the new type of recessed markers are in place on the southbound 14th Street bridge, on Calvert Street between Rock Creek Park and Columbia Road, and in a few other locations. They will be installed on the Southeast-Southwest Freeway as it is reconstructed over the next five years, he said. There is no plan to do the entire city this way, he said, because the new markers are "10 times more expensive than paint."

Pastor said the new markers cost $10 each installed. There are lots of other needs for road money, and many of them involve safety, too, but considering the danger, this seems like one that should receive a top priority. Post Mortem on Potholes

There have been enough letters and comments about the notorious Cabin John Bridge pothole the third week of January that there should be a post mortem. The "Pothole from Hell," as one reader dubbed it, seemed to grind morning rush-hour traffic to a halt 10 miles or more into Virginia much of the week, and mystify many motorists as to why it took so long to fix the problem.

Snyder, the Maryland traffic chief for Montgomery and Prince George's counties, said that the problem was not one, but three potholes that opened that week in the Cabin Branch Bridge, which carries Beltway traffic and is located about 500 yards further into Maryland than the American Legion Bridge at Cabin John.

The first pothole, about 2-by-2 feet and 10 inches deep -- all the way to the reinforcement rods -- was discovered about 6 a.m. by road crews on Monday, Jan. 18. A crew was dispatched to Gaithersburg to bring a steel plate for the pothole. The pothole and then the repair around 9 a.m. turned 40-minute commuting trips into two hours or more.

A separate pothole, same size, with the river showing underneath, was discovered Tuesday morning, also about 6 a.m. The permanent patching of the Monday pothole and the new pothole took care of Tuesday's morning rush hour. Then on Wednesday, yet a third similar but separate pothole was discovered on the same bridge. All the potholes received steel plates during the week and were permanently filled by Saturday, but by then a lot of drivers had suffered through an excruciating week. The nearby American Legion Bridge, with 150,000 cars a day, is about the busiest bridge in the metropolitan area.

Snyder said that while the Cabin John Bridge was recently redecked, the Cabin Branch Bridge needs the same treatment. Current plans call for that to be done as part of a project to widen the Beltway from six lanes to eight between the Cabin John Bridge and River Road. That project is scheduled to begin in the spring of 1990 and take about three years.

Meanwhile, Snyder said the state has moved up from 7:30 a.m. to 6 a.m. the time someone will be on duty who can receive calls from the field and notify radio stations of major impediments to commuters. "At least that gives commuters a fair shot to know what's going on," he said. But he added that "if the Cabin John or Cabin Branch Bridge goes down, there is no good alternative. The best thing to do is to delay leaving, or go all the way around the Beltway the other way." And Still More Resolutions

Many readers accepted an invitation to offer New Year's resolutions to area road officials, and here are more. Drivers can continue to suggest them and we'll pass them along as space permits.

Many accidents can be prevented by inserting reflectors along highways -- particularly the Beltway. During rainy or cloudy nights {white lines} cannot be seen in places. This is vital to night driving. Rte. 50 near Fair Oaks Mall has some strategically placed reflectors. R.G. RUFF Fairfax

This was another of those letters that prompted today's column.

As a suggestion for traffic bottlenecks in the Western Avenue area near Wisconsin Avenue, Connecticut Avenue and River Road: Put a left-turn arrow back at Western Avenue and Reno Road {34th Street} going west so that drivers can make a left turn onto Reno without having to go through only on a red light. There used to be an arrow and it worked well. JEAN MEISEL Chevy Chase

Anyone who drives through Rock Creek Park north of the tunnel {at the zoo} knows that this is a difficult and dangerous task -- especially at night. There are road lights that have not worked in the 2 1/2 years I have lived here. I am certain that if whoever is responsible for their operation turned them on again it would make this road a lot safer to drive after dark. JERRY NEBEN Washington

Gov. Schaefer's electronic signs on the way to the beach informing motorists of road conditions are helpful.

Even more helpful would be such signs at each entrance to the Beltway to inform motorists of tie-ups and slowdowns ahead, so that they could choose to use alternate routes instead of becoming trapped in those exitless hells. I know such a system would be expensive, but the savings in resources and time might well offset that expense. MARY SEYMOUR Silver Spring

My hope for the New Year is that the Virginia Highway Department will finally come to a decision on resolving the mess in McLean at Westpark Drive and Rte. 123. This has been in the Highway Department's program since 1981 but it continues to be shown as "deferred" in the highway project listing occasionally published in the Fairfax County's "Weekly Agenda." Now that the prodevelopment forces, represented by John F. Herrity and Nancy K. Falck, have departed from the County Board of Supervisors, perhaps a solution can be reached and work begun. WILLIAM W. WATKINS Annandale

My New Year's suggestion for better driving is installation of reflecting disks on lane markings, particularly on multilane roads. They are widely used in the West. Night and rainy weather driving are much easier. EVELYN WHITAKER Silver Spring

Dr. Gridlock appears in this section each Friday to explore what makes it difficult to get around on roads, from misleading signs to parking problems to chronic bottlenecks. We'll try to find out why bad situations exist and what is being done about them. You can suggest topics by writing to GRIDLOCK, c/o The Washington Post, 1150 15th St. NW, Washington, D.C. 20071.