Chart shows Metrorail’s on time performance rates since the Silver Line opened last summer. (WMATA image)

Just before the holiday weekend, I got an e-mail from a Cleveland Park resident asking what time she should leave home  July 4 to park at Union Station, where she needed to be by 2 p.m. I made my suggestion, and during our exchange she said in passing, “Ordinarily, I’d think maybe Metro, but now, not so much!”

This has become a common theme in my exchanges with travelers: They just assume a Metrorail trip will be unreliable, just as many drivers assume their commutes will take a lot more time on some days than on others.

It’s one of many reasons that Metro board members should let the transit staff go ahead and talk to riders about the new proposal to put more spacing between the trains on five lines.

[Join me at noon Monday for an online chat about Metrorail and other travel issues.]

The proposal itself is dramatic: To make the schedule more reliable, the staff proposes to increase the time between trains on four of those five lines. The scheduled gaps at rush hours would increase from six to eight minutes. The Blue Line would be the exception. Spacing trains eight minutes apart would make service more frequent, because they’re now scheduled to operate 12 minutes apart, the biggest gap in the Metrorail system.

This is likely to raise concerns among Metro board members as well as riders. It’s a service cut. And even though Metro would add more cars to the remaining trains, the transit staff still expects that the trains would become more crowded. That includes the Blue Line, because the riders who left that line for the Yellow Line Rush Plus service would shift back to Blue, since the proposal includes killing Rush Plus service.

People who board on sections served by only one line will be particularly concerned. These include the far west portion of the Orange Line, the southern and northern portions of the Green Line and the southern part of the Yellow Line.

Even though Metro says that, collectively, the Silver Line’s five new stations aren’t generating the anticipated ridership, the end of the line station at Wiehle-Reston East is very popular with drivers, bus riders and bikers. They’ll certainly be concerned about a reduction in rush hour train service.

Aside from these issues about specific rides, the big picture is quite concerning. This is not a proposal to bring service back from a few bad months and then move on. It’s an acknowledgement that the addition of the Silver Line last year overtaxed the rail system and it may take Metro years to recover.

Making these changes would require public hearings, board approval of a specific plan, a change in the board’s standards on the spacing between rush hour trains, months more of planning for operational changes and a redo of the Metro maps, brochures and station signs. At the earliest, it would happen in the first part of 2016, and probably wouldn’t change again for a few years.

Given all that, why would I say the Metro board should go ahead and put this proposal out for widespread public discussion over the next few months?

Acknowledging a problem. It’s the first step toward recovery. The transit staff says it can see that on-time performance has declined since the Silver Line opened last summer. Yes, the harsh winter was a problem, but it explains only a few bad months. Metro doesn’t have as many of the new rail cars as it hoped during Silver Line planning, maintenance of the existing rail car fleet has suffered and Metrorail controllers are trying to get more trains through the track junctions than the current system can handle.

It’s a proposal. The most encouraging development is that Metro has a proposal to offer. It’s been half a year since Metro general manager Richard Sarles retired, and the board shows no signs of picking a successor. But the transit staff hasn’t sat around awaiting developments.

We can talk about it. The staff isn’t saying, “Here’s our plan. We just need the board to okay it.” The staff will be asking the board for permission to advance the idea to a phase of widespread public discussion. The discussion will involve two of the top concerns riders have: the reliability of the schedule and crowding on the trains.

I don’t recall a time when the transit authority created a formal environment for a discussion of those basic issues. The periodic hearings about fare increases or budget-related service cuts are very different forums. People come in with very personal complaints about the proposed elimination of bus stops or bus routes.

This new round would be a chance not only to address specific concerns about the proposal but also to air concerns and ideas about the rail system’s overall reliability and the comfort of riders.

When it meets  Thursday, the Metro board’s Customer Service and Operations Committee should advance this proposal to the next round.