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Table 3. LRT alignment classification.
Class Category Description of Access Control
Exclusive Type a Fully grade separated or at-grade without crossings
Type b.1 Separate right-of-way
Semi-exclusive Shared right-of-way, protected by barrier curbs and
Type b.2
fences (or other substantial barriers)
Type b.3 Shared right-of-way, protected by barrier curbs
Shared right-of-way, protected by mountable curbs,
Type b.4
striping and/or lane designation
Type b.5 LRT/pedestrian mall adjacent to parallel roadway
Non-exclusive Type c.1 Mixed traffic operation
Type c.2 Transit-only mall
Type c.3 LRT/pedestrian mall
Source: TCRP Report 69 (1)
and suggested the following sequence for route alignment environment. Many agencies reported that left-hand turn
choices in order of desirability (2): collisions are a significant issue. These collisions are avoided
in areas where left hand turns are physically restricted. Phys-
· Exclusive alignment (Type a), ical separation of general traffic from the LRT remains the
· Separate right-of-way (Type b.1), best way to prevent collisions, but it is not always the most
· Median alignment protected by barrier curbs and/or fences efficient or desirable from a cost or ridership perspective. This
(Types b.2 and b.3), is because the needs of other modes and the need for access
· Median alignment protected by mountable curbs and must be considered when designing a light rail system. Phys-
striping (Type b.4), ical separation, where feasible, can include a combination of
· Operation in reserved transit malls or pedestrian areas separate alignments, grade separation at intersections, and
(Types b.5, c.2, and c.3), and fencing/barrier systems.
· Operation in mixed traffic (Type c.1).
Top LRT Safety Issues
After considering safety, some additional issues can also be
addressed. For example, Type a alignments, where the LRT is The objective of the literature review and the consultations
completely separated from the road and pedestrian network, with LRT operators was to identify the most significant safety
allow LRVs to reach high speeds, but may be difficult for rid- issues along LRT alignments. Identification of safety issues is
ers to access from surrounding areas. These types of alignment a useful step in the selection of safety treatments, as it permits
are most often served by park-and-ride lots or other transit the selection of specific treatment(s) for a problem rather
modes. Type b and Type c alignments create more exposure than general or default measures.
to safety issues, but they offer the advantage of providing more The first three lists of safety issues presented in this section
direct access to a variety of land uses (3). summarize the main LRT safety issues according to TCRP
This report is concerned with the interactions of pedestri- Report 17, TCRP Report 69, and the site visits conducted for
ans and motor vehicles with LRT alignments, and addresses this project. The lists are extensive because of the need to
both Type b and Type c alignments. It does not address Type recognize a wide variety of different alignments and local
a alignments as Type a alignments are designed to eliminate considerations, and because much of the information is
pedestrians and motor vehicle interactions, except in unusual anecdotal rather than quantitative in origin. The lists have no
or extraordinary circumstances (e.g., trespassing). statistical significance, but provide a broad view of the types
In all the various systems visited, the LRT staff noted con- of issues that LRT agencies and SSOs are facing and trying to
siderably different operating behaviors between the down- mitigate.
town street-running sections and the more suburban restricted The fourth list condenses the three lists into the top five
right-of-way (ROW) sections. In at least one case, LRT staff safety areas facing LRT agencies.
commented that transit operators felt that they noticeably TCRP Report 17 (2) investigated 10 transit agencies with
relaxed when entering a restricted ROW section after navigat- operating speeds of less than 35 mph (55 km/h). The authors
ing a much more complex mixed traffic median-running identified some common safety-related problems faced by
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LRT agencies through agency interviews, collision analysis,
Track clearance phasing
and field surveys.
Excessive queuing near LRT crossings
These were:
Turning vehicles hesitate during track clearance interval
Vehicles queue back from closed gates into intersection
· Pedestrian safety:
LRT crosses two approaches to a signalized intersection
Trespassing on tracks (diagonal crossing)
Jaywalking Motorist confused about gates starting to go up and
Station and/or cross-street access then lowering for a second time, when a second LRV
· Side-running alignment arrives from the opposite direction
· Vehicles operating parallel to LRT's ROW turning left across LRT versus emergency vehicle pre-emption
tracks: Turning motorists violate red protected left-turn indi-
Illegal left turns cation due to excessive delay
LRV pre-emption violating motorists' expectation of With leading left-turn phasing, motorists violate red pro-
protected left-turn signal phases tected left-turn arrow moving on the green phase when
· Traffic control: trains also turn
Passive turn restriction sign violations · Automatic gate placement:
Active turn restriction sign violations At angled crossings or for turning traffic, gates descend
Confusing traffic signal displays on top of or behind motor vehicles
· Pedestrian control:
Poor delineation of dynamic envelope
· Motor vehicles on tracks Limited sight distance at pedestrian crossing
· Crossing safety (right-angle crashes) Pedestrians dart across LRT tracks without looking
· Poor intersection geometry
The five agencies consulted during the site visits for this
project noted a variety of safety issues. The issues cited by these
TCRP Report 69 (1) investigated 11 LRT lines with operat-
agencies as being the most important safety concerns are:
ing speeds greater than 35 mph (55 km/h). The common
safety-related problems identified were:
· Jaywalking between marked crossing locations (i.e., mid-
block, at stations, etc.);
· System division:
· Trespassing at stadium stations after events;
Vehicles drive around closed automatic gates · Pedestrians crossing against signals and/or against warning
LRV operator cannot visually confirm whether gates are
devices;
working · Pedestrian collisions due to a "second train";
Slow trains share tracks/crossings with faster LRVs and · Pedestrian inattention and/or distraction;
near-side LRT station stops · Increased severity of pedestrian collisions;
Motorists disregard regulatory signs at LRT crossings · Pinch points on platforms;
and grade crossing warning devices · Risky behavior by cyclists;
Motor vehicles queue back across LRT tracks from a · Vehicles trapped inside gates;
nearby intersection controlled by STOP signs (MUTCD · Vehicles crossing tracks despite gates, signals, and/or
R1-1) warnings;
Sight distances are limited at LRT crossings · Vehicles stopped on tracks due to queuing in peak traffic
Motor vehicles queue across LRT tracks from down- periods;
stream obstruction · Collisions in left turn lanes shared with LRT tracks;
Automatic gate and traffic signal interconnect mal- · Left turn collisions, especially where the LRT operates in
functions the center alignment;
· System operations: · Right turn collisions, including collisions that occur on
Freight line is shared with LRT unusual alignments or where right turn on red is prohibited;
Freight line was converted to LRT line · Sideswipes on Type b.4 and c.1 alignments;
Collisions occur when second LRV approaches pedestrian · Motorist confusion such as driving on restricted ROW;
crossing · The public's level of respect for LRV is less than that for
Motorists disregard grade crossing warning devices heavy rail;
· Traffic signal placement and operation: · System inconsistencies that impact motorist and pedestrian
Motorists confused about apparently conflicting flashing expectations; and
light signal and traffic signal indications · LRV operator error.
