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One way? No way!

One-way sidepaths don't make for efficient, short trips. Any trip that requires travel on the opposite sidepath and does not start exactly at a crosswalk must start with travel away from the destination, and if it does not finish exactly at a crosswalk, it must overshoot the destination and double back.

All of the high-traffic campus destinations along the block of Vassar Street with sidepaths are on the south side. The sidepaths on both sides are behind curbs. The westbound sidepath is also behind a row of parked cars over most of its length. Getting from one side to the other is not easy at most locations.  Therefore, both of the following statements are incorrect, even though they contradict each other. The major desire lines are not accommodated by one-way use of the sidepaths, and so bicyclists use them for two-way travel.

Between intersections, cyclists will travel on one-way cycle tracks located on each side of Vassar Street.

Paul Smith, of Rizzo Associates,
consultant to the Vassar Street project,
in a defense of the project,
May 2002

I think that's an assumption that we've made [that people will go against traffic]. We have thought about the strongest desire lines. The problem is with the small ones.

Susan Clippinger,
Director of Traffic,
City of Cambridge,
at Mar. 6, 2002 meeting

Satisfying some real desires

Let's look at some of the desire lines. The bicycle rack in front of Building 34 is a major destination for bicyclists. The bicyclist in the photo below was riding on the sidepath on the west side of the street (left side in the photo), turned out into the street from a driveway, and is dismounting in the middle of the street to lift his bicycle over the curb and reach the bike rack.

If the bicyclist had been riding in the street, he would still have had to dismount to get up the curb, but he at least could have established his right of way, merged to the center of the street, then turned left, instead of swerving out in front of the bus. He was fortunate that the bus driver's seat is high enough to allow a view over the top of the parked pickup truck. Few drivers sit so high.

Bicyclist crossing Vassar Street to reach Building 34 bicycle rack

DSCF0017crossover to bldg 34.jpg (31375 bytes)

If there were a ramp up from the street to sidewalk level -- a bicycle driveway -- in front of Building 34, the bicyclist could have exited the street before dismounting,, though he would have had to ride up into the sidewalk area, possibly conflicting with pedestrian traffic. If the street had been kept at its original width with parking on both sides, the bicyclist could have found refuge between parked cars in the parking lane to dismount. But the trendy, clever idea of narrowing the street to supposedly calm traffic carries the intention instead that the bicyclist should always be riding in the sidewalk area, and should continue past Building 34 to the crosswalk in front of Building 38 and double back (see map, below: Building 34 is in the lower right corner). The bicyclist did not have the patience to lengthen his trip and so he dismounted in the travel lane.

The Building 39 Portal

MIT's Building 39 portal is not a "small one" as trip endpoints go. It is the main entrance to the internal street network of the main campus, and leads to many loading docks, faculty parking spaces and bicycle racks. The portal has two separate roadways, one for inbound traffic and the other for outbound traffic.

The bicyclist shown below, almost certainly an MIT student with an IQ in the 95th percentile or higher, is inbound on the outbound roadway of the Building 39 portal. He is not wearing a helmet, and illegally carrying a bag that could swing into the spokes of the front wheel. Crossing from right to left as he is doing has several times the crash rate of crossing left to right -- a motorist exiting here would normally be looking left for traffic.

An Airborne Express truck is parked where it partially blocks the view to the left, so a motorist headed out to the street (away from the camera) would have to pull forward past the truck before looking left for bicyclists traveling in the intended direction on the sidepath.

Bicyclist sorely in need of good advice enters Building 39 portal.

DSCF0073portal.jpg (27176 bytes)

Why do bicyclists enter the wrong side of the Building 39 portal? To reach the portal from the east (starting at A in the map below) by using the sidepaths as intended, a bicyclist must ride past the portal several hundred feet to the crosswalk at Massachusetts Avenue (beyond D in the diagram). The bicyclist must make a U turn at that crosswalk, and then ride back to enter the portal at point E.

It's much more likely  that the bicyclist will cross Vassar Street using the driveway C and/or crosswalk B, travel east on the westbound sidepath, and then south in the northbound roadway of the Building 39 portal at F. The abrupt swerves into the roadway and the wrong-way travel are unpredictable, unexpected and hazardous.

Route from the east to the Building 39 portal:
Using sidepaths as intended: black arrows.
Shorter , more appealing routes: red arrows.

east.gif (12843 bytes)

It would be in MIT's interest to work to prevent such problems, both of behavior and of design, so more of its students might become alumni donors and fewer, organ donors. Yet an MIT planner has indicated that there is little need for education with this logically designed facility. As if this facility were logically designed, and MIT were not in the education business, and MIT students were particularly hard to educate...

Abandon all illusions, ye who enter here

Behind Building 39 -- at the bottom of the map above -- the gated entry from the portal into the campus also encourages wrong-side travel. In the photo below, looking away from Building 39, we see a bike lane about 5 feet wide, designated for two-way travel. Two-way bike lanes like this have been shown highly hazardous, violate all applicable design guidelines, and instruct bicyclists to violate the traffic law. This one is especially hazardous because the roadway is so narrow that there is no way to avoid head-on conflicts with motor traffic. This installation has nothing whatever to do with engineering.

Bicyclists and motorists could form a single line to share the inbound or outbound roadway for one-way travel, though it would help if there were more room for bicyclists to get around the end of the inbound gate, which is longer than the outbound gate. Maybe the saw that was used to cut the outbound gate dulled before the inbound gate could be cut?

Two-way striped bike lane on the outbound roadway to the Building 39 portal.
(Arrow points to bike lane sign). There is no bike lane in the inbound
roadway (right side of photo). Click on the
Next>> link below to view the
progress of a bicycle and motor vehicle through this area. Decide for yourself:
is the outbound roadway suitable for two-way bicycle and motor traffic? Is the
bike lane suitable for two-way bicycle traffic?

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Sequence of traffic movements (Javascript-enabled images)

This Web page began with some quotes. Another quote is especially relevant at an engineering institution:

Engineering Judgment - the evaluation of available pertinent information, and the application of appropriate principles, Standards, Guidance, and practices as contained in this Manual and other sources, for the purpose of deciding upon the applicability, design, operation, or installation of a traffic control device. Engineering judgment shall be exercised by an engineer, or by an individual working under the supervision of an engineer, through the application of procedures and criteria established by the engineer. Documentation of engineering judgment is not required.

U.S. Federal Highway Administration,
Manual of Uniform Traffic Control Devices

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