Friday Roundtable: Metro Trolley Wire Map

While most people looking at the sky today are hoping to see fireworks, I prefer to look at overhead trolleybus wires. The map below outlines the location of all trolleybus wires in Seattle. This dataset was created by King County and last updated in 2018. While the map has not been updated in 7 years, it is still mostly up to date. The biggest change not reflected in the map is the removal of trolley wire from Madison St from the RapidRide G Line construction. The official map and dataset is available here.

Screenshot of the trolley wire map. Click here to view the interactive map.

Many of the trolley bus routes that run today are immediately identifiable. Looking past the wires that are used by today's routes, the map shows two other types of overhead wire: deprecated route wire and what I'm calling utility wire".

Deprecated Route Wire

Like all bus routes, Seattle's trolleybus routes have gradually shifted over time. When a route changes, new trolley wire may need to be installed to support the new alignment. The old trolley wire is rarely removed. In Queen Anne, there is a wire loop around John Hay Elementary School that extends from Queen Anne Ave along Blaine St and 2nd Ave. While no routes currently use this wire, the loop served as the tail of Route 4 until 2017.

Slightly further north, there is another wire loop on Queen Anne Ave, Raye St, 3rd Ave, and McGraw St. The McGraw St segment is still used today by routes 4 and 13, but the rest of the loop is no longer used. Similar to the previous loop, this wire was used by Route 3 until 2017.

Utility Wire

In addition to the overhead wire used for past and present routes, the map shows wire used for storing, deadheading, and turning around trolleybuses. Metro's current trolleybus fleet of New Flyer Xcelsior have small batteries that allow the buses to operate for a few miles of off-wire. Previous trolleybuses vehicles had to be connected to overhead wire at all times, and the utility wires allows buses to take a more direct path when deadheading to the start of a route. Examples of utility wire include the left turn from Rainier Ave S to S Plum St for Route 4, and the wires connecting the ends of routes 1 and 2 in Queen Anne.

Trolley Wire Expansion

Despite the Metro's zero emissions by 2035" goal, only Route 48 is planned to be converted to use trolleybuses. Route 48 runs on 23rd Ave and already mostly covered by overhead wire, thanks to routes 4 and 43. Electrification of the route is expected sometime in 2026. To achieve zero emissions, Metro is investing in battery electric busses for it's non-trolley routes. While both systems have pros and cons, Metro should make the most of it's existing trolley wire network and the new batteries it is installing in the existing trolleybus fleet. What other routes could be updated to use trolleybuses with minimal new wire or with short off-wire segments?

This is an open thread.