Roadway Capacity (RC)
Table 5-8
Roadway Level of Service Ratings
Roadway capacity relates to the ability of existing interstates, highways,
arterials, and other local roads to provide adequate mobility and access
between military installations and their surrounding communities. As urban
development expands, roads once carrying limited local traffic begin to
function more as urban major arterial roadways. These roads often become
the main transportation corridors for all traffic from residential to
commercial trucking, including access to military installations. As
transportation systems grow and demand more capacity, these facilities
become congested and create delays for both military and non‐military
automobile users.
LOS Rating
Definition
A Represents a free‐flow operation. Vehicles are
almost completely unimpeded in their ability to
maneuver within the traffic stream.
B Represents reasonably free‐flow operation.
Ability to maneuver within the traffic stream is
slightly restricted.
C Represents a traffic flow with speeds near or at
free‐flow speed of the freeway. There is
noticeable restricted ability to maneuver within
the stream of traffic.
D Speeds begin to decline with increased density.
Ability to maneuver within the traffic stream is
noticeably limited.
E Operation is at capacity. Vehicles are closely
spaced within the traffic stream and there are no
useable gaps to maneuver.
F A breakdown of vehicle flow is present. This
condition exists within the queues forming
behind the breakdown points.
ACCEPTABLE
Key Terms
Level of Service. Level of Service (LOS) is a common measurement used by
traffic engineers to determine the effectiveness of a traffic system. This
grading system assigns a letter grade from A to F to roadways and
intersections based upon traffic flow and safety characteristics as shown in
Table 5‐8.
Roadway Capacity. Roadway capacity refers to the ability of existing
freeways, highway, arterials and other local roads to provide adequate
mobility and access among military installations and their surrounding
communities.
Background Report
UNACCEPTABLE
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