The virtual tunnel that Metro established a year ago to help riders switch between the Farragut North and Farragut West stations is attracting about 600 transfers each weekday, according to the agency.

Metro started the free transfer it calls Farragut Crossing on Oct. 28, 2011, letting riders re-enter the system for free when switching between the two stations and lines. Now one year old, it handles about 15,000 transfers per month, with roughly 600 transfers on weekdays and about 100 on weekend days.

The number of riders using the transfers has grown steadily. The first full week last year averaged 325 transfers per weekday. Less than two months later, the average had grown to 454 riders per weekday. Even so, the transfers represent a small number of the some 745,000 trips the agency runs each weekday on the rail system.

The numbers are consistent with Metro's expectations, agency spokeswoman Caroline Lukas said. But that doesn't mean the transit agency is planning to go ahead with another possible transfer quite yet.

"While there are no immediate plans for new virtual crossings, we may contemplate one in the future between Metro Center and Gallery Place as part of the Momentum strategic planning process," she wrote in an email.

The transfer helps riders switch between the Red and Orange/Blue lines without needing to travel to Metro Center, a potential boon for someone traveling from, say, Bethesda to Rosslyn. However, the time saved depends on the timing of trains -- and Farragut Crossing is decidedly less appealing on bad weather days. Riders have 30 minutes to exit one station and re-enter the other, which local businesses had sought so riders could shop en route.

It also takes some of the pressure off Metro Center and gives riders an alternative during a breakdown or other delay.

Metro has talked before about building an actual tunnel between the two stations that straddle Farragut Square. The stations have a track connecting the lines, as some riders learned earlier this month when the agency had to limit service on the Orange and Blue lines there when a rider committed suicide on the Red Line at Farragut North. But the agency only uses it to move out-of-service trains between lines.

An actual pedestrian tunnel was nixed due to concerns about costs. The virtual tunnel still cost Metro an estimated $500,000 because it entailed months of computer programming and testing to let SmarTrip cards and faregates recognize the transfer. Metro also asked the District to repair some sidewalks and curbs in the area to smooth the walk between the two stations.