The Blue Line riders who have been complaining about the reduced service to certain Metro stations under the Rush Plus program aren’t going to like the new plan for Silver Line service any better.

When the line opens, perhaps by the end of next year, Metro will further reduce the number of Blue Line trains, according to a staff plan prepared for presentation to the Metro Board on Thursday. [Lori Aratani has more details about the Metro service plan.] The trains will be scheduled to operate every 12 minutes along the route between Franconia-Springfield and Largo. That will be the service level during both peak periods and off-peak periods.

Commuters who ride between Virginia and the middle of D.C. will be a bit better off than today. Every third Blue Line train will become a Yellow Line train traveling between Franconia-Springfield and Greenbelt.

Those morning commuters who work around Rosslyn and the west side of D.C., or who transfer at Rosslyn for the Orange Line in the direction of Vienna will be worse off, because they can’t take advantage of the extra Yellow Line service or any other Metrorail service.

The Metro staff did consider alternatives, but concluded that none would offer better service while still accommodating the Silver Line trains. The first segment of that line will operate between Wiehle Avenue in Reston and Largo. That is a change from the original plan, which would have put the line’s eastern terminus at Stadium-Armory. But as Lori Aratani described in her story, Metro officials concluded that using the pocket track near Stadium-Armory to turn back trains would be unworkable.

Despite that change, riders on the east side of the region will wind up with the same level of service they have now. The biggest change for them is that Silver Line trains will replace the Rush Plus Orange Line trains to Largo.

The bigger impact of the rearranging to accommodate the Silver Line will be on the west side. Metro can’t put any more than 26 trains per hour through the tunnel at Rosslyn for the trip to and from downtown D.C. Silver Line trains are scheduled to operate every six minutes at rush hours. On their eastbound trips, Silver Line trains will join the Orange Line outside East Falls Church and head for the Rosslyn tunnel.

So how do you get three lines through there? “It’s a zero sum game,” said Metro spokesman Dan Stessel.

The math works only by reducing the number of Orange Line trains going through while further cutting back on the Blue Line service. For Orange Line riders, the effect is limited. After the Silver and Orange lines join at East Falls Church, they will have the same number of trains as they do today. Between Vienna and East Falls Church, they will have fewer trains, because some will be shifted to the Silver Line.

But Metro estimates that zone will also have fewer riders. Some who now use those outer stations will shift to the Silver Line’s Wiehle Avenue station. They will do so partly because some feeder bus routes will be shifted there, too.