A United Streetcar prototype in Portland.

Previously, we looked at the various streetcar power systems in use worldwide and the visual impact of overhead wires. To summarize, overhead wires are cheaper and more proven, and government attorneys believe DC can overturn the ban on wires in the L’Enfant City on its own. However, NCPC and Congress may try to block such an action unless there can be a reasonable compromise. Is there?

Many of the streets in the L’Enfant City, such as H Street, won’t become ugly simply because of a few overhead wires. As commenters have noted, we already have overhead streetlights, traffic signals, trees and more. However, NCPC may have a legitimate concern about protecting important “viewsheds,” such as the radial avenues that emanate from the Capitol or the White House. Likewise, having wires cross the Mall is probably a non-starter, and likely undesirable as well.

Further, as you noticed from reading the overhead wire article, wires are much more visible where routes curve or intersect. A single wire can propel a streetcar along a straight segment of street; at an intersection, there must be more wires, and if a roadway curves gently, the wire requires more closely-spaced anchoring wires to turn it along with the roadway.

Is there a solution? DDOT Director Gabe Klein explained DC’s likely approach at a DC Council hearing last week about the 11th Street Bridge. (Fast forward to 55:10.) Klein explained that they’re talking to United Streetcar, a Portland-based streetcar manufacturer, which is working on hybrid vehicles that can run on overhead wires but also “drop the catenary” to switch to battery power. These vehicles can operate for up to a mile without the overhead wires. Otherwise, the vehicles are compatible with those made by Czech manufacturer Skoda, three of whose vehicles DC currently owns (and, Klein explained, DDOT hopes to move to DC by the end of the year).

DDOT is also continuing to look into other hybrid technologies, many of which are evolving very quickly. In addition to Alstom’s STEEM, which uses supercapacitors, Infrastructurist’s Yonah Freemark pointed out SWIMO, another regenerative-braking system using batteries that’s already been tested in Japan for over two years.

Ultimately, we’ll most likely end up with one of these hybrid systems which uses wires in some areas but also allows gaps in sensitive areas. If the major viewsheds, intersections and curves are the major problems, why not simply leave those out? Here’s a map of what the network could look like inside the L’Enfant City, based on the alignments in the 2005 DC Alternatives Analysis:

The purple areas show possible gaps. Every segment on a radial avenue from either the White House or Capitol includes a gap, such as Farragut Square crossing Connecticut Avnenue. There would be no way to see a single wire from the Capitol or White House. Some might not really need gaps, such as Delaware Avenue in Southwest, where you can’t actually see the Capitol thanks to the freeways in the way. Likewise, all turns and curved segments get gaps, as does the portion past Congressional office buildings and the Mall.

The longest of these segments is less than one mile, except for the portion from Washington Circle through Georgetown. Georgetown is very unlikely to ever accept overhead wires, and so any streetcar plan that includes a line in Georgetown needs to find an alternative. If the United Streetcar stop can recharge at stations, like STEEM can, that could boost the streetcars over the mile limit. Plus, Georgetown is nowhere near the top of the list for streetcar segments. By the time DDOT is ready to build any line to Georgetown, if ever, the technology may have further advanced.

Another option would be to route any Georgetown streetcar along K Street instead of M. The original K Street Transitway study (PDF), which also recommended creating the Circulator service along K Street that now exists, recommended buses use K Street, under the Whitehurst Freeway, in one direction. Georgetown may well be less resistant to overhead wires beneath an overhead freeway. Such a route would also let streetcars use the underpass at Washington Circle.

DC and NCPC should work out an agreement. DC should promise to protect key viewsheds and otherwise design the system to minimize the visual impact. In exchange, NCPC should drop its opposition to any overhead wires in the L’Enfant City. DDOT can identify the best technology that uses wires in most areas but switches to an alternative power source where needed. An absolute ban on wires will force DC to either build an extremely expensive system or none at all, while unfettered use of overhead wires will indeed mar some of DC’s iconic and unique views along major avenues. A hybrid is the most reasonable compromise.

David Alpert is the founder of Greater Greater Washington and its board president. He worked as a Product Manager for Google for six years and has lived in the Boston, San Francisco, and New York metro areas in addition to Washington, DC. He lives with his wife and two children in Dupont Circle.