Mar

Not-So-Shiny Silver Line (Part I)

Posted by admin Published in Transportation Alternatives

Part I. Underground Section is Too Slow:

Boston, like Seattle, has a different bus system, where buses travel underground, stopping at stations like a subway. The three station tunnel, however, is actually one of the slower sections of the Silver Line bus, even though there are no traffic interferences. Buses only average 12 mph (19 km/h) in the 1.5 mile bus tunnel (including the instance to stop at three stations), much lower than on the streets (average of 15 mph for SL3 surface section to City Point including stations). The main reason, possibly, of why buses must slow down once entering the subway tunnel is considering of buses do not run on tracks. Drivers must steer through a narrow tube, and since there is only a couple of feet on each side of the vehicle, it would be easy to scrape against the wall. Boston’s transit agency, the MBTA, should consider

using a guided bus system in the tunnel. Guided buses use a style of tracks (usually a concrete kerb) that steers the bus. Like trains, the tracks will guide the bus precisely along a positive path. For that kind of system to be effective, special wheels that spin horizontally need to be attached. The longest guided busway in Adelaide, Australia (known as the O-Bahn) can attain speeds up to 62 mph (100 km/h), while average speeds on the route are at 37 mph (60 km/h) including stops. With higher speeds, the Silver Line can finally become a “rapid transit” line.