The new 7000-series trains began to arrive this spring. Meanwhile, Metro was scrambling to provide cars for the Silver Line. (Matt McClain/The Washington Post)

Last summer, Metro got the Silver Line. This summer, riders on the Red, Orange and Green lines get the bill.

The transit authority is launching a rail car maintenance program to make up for the stresses that the new service added to the old system.

There was a time in the Silver Line planning process when Metro hoped to have a bunch of the new 7000 series rail cars in service for the grand opening. When it became apparent that the new cars wouldn’t arrive in time, the transit staff revised its plan. That meant stretching the existing fleet.

One of the ways to accomplish that was to limit the time cars spent in the shop for routine checks. But routine checks are a way of discovering problems with brakes, doors and air-conditioning before the trains enter service for the day.

With new limits on these routine checks, it became more likely that a problem would be discovered only after a train began picking up passengers. When more than 100 trains are operating, one brake problem on one car messes up a rush hour for thousands of commuters.

By now, many Metrorail riders are aware that the transit authority will sharply cut back on eight-car trains on three lines this summer so that the rail fleet’s worst-performing cars can spend more time in the maintenance shops.

They also may have heard that most eight-car trains vanished this past week for a separate reason: an emergency inspection of all 100 of the 4000 series cars after the doors on several opened while trains were moving. (The cars may be back by Tuesday.)

But Metro chose an odd way to announce all of this. Many riders I heard from got it from the train operators over the loudspeakers as they went to work.

While it’s always good for the transit system to communicate directly with its customers, this particular choice was weird, leading to confusion and consternation among riders.

Dear Dr. Gridlock:

On Monday during the morning rush on the Red Line, the operator said that Metro is limiting service to six-car trains on “Monday, Wednesday and Friday” because of low ridership.

I get on at Shady Grove, and by Rockville, all seats were filled — and by Twinbrook, the aisles were crowded. Clearly, there were plenty of people trying to get to work Monday. And maybe after the schools close it might make sense to eliminate eight-car trains on Mondays and Fridays, even during rush hour. But Wednesdays?

A side note: This was one of the few times that the operator’s announcements could be understood.

— Joseph Antos, Gaithersburg

Riders are used to hearing train operators say things like, “Stand clear. Train moving forward.” Historically, the train loudspeakers are not the riders’ primary source of information on strategic changes­ in safety, maintenance and customer-service programs.

As Antos noted, many people hear only garbled versions of those speaker announcements. And if they did hear this brief announcement and wanted more information, what were they going to do? Line up at the intercoms and pepper the train operator with more questions?

This is no way to run a railroad that moves people rather than freight.

Wednesday afternoon, Metro put out a statement announcing what was actually happening, and Deputy General Manager Rob Troup elaborated at Thursday’s Metro board meeting. But Metro should have gotten the word out to riders before Monday morning commuters started to notice the eights being replaced by sixes on the next-train message boards.

And even if riders then heard a clear announcement aboard their trains, the message they took away didn’t match what Metro was saying by midweek.

The cutbacks are not “Monday, Wednesday and Friday.” Cutbacks to inspect the 4000 series cars went on through the week. The summertime cutbacks for additional maintenance time will be on Mondays and Fridays.

The cutbacks are not occurring because of low ridership. Metro spokesman Dan Stessel said the savings from running six-car trains is negligible.

Commuter ridership does dip during the summer. And throughout the year, ridership tends to be 10 percent less on Mondays and Fridays, because of the way people schedule their workweeks. The ridership pattern was a factor in selecting the weekdays for cutbacks, but the overall strategy is about maintenance and not about Metro’s financial problems.

But essential messages that riders didn’t pick up — even in garbled fashion — were that the immediate cutback stemmed from the need to check train doors for safety and that the summertime cutback is meant to compensate for months of deferred maintenance.

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@