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Year
2030 projected levels of service : segments
"Level
of Service" (LOS) for road segments is a crude
measure of the sufficiency of existing or proposed roadway capacity.
In San Diego, LOS is assessed based on the volume to capacity
(v/C) ratio, which is proportional to the average
number of daily trips (ADT) on a given road segment, divided by
the total number of lanes. LOS grades are similar to school grades:
A is excellent and F is failing.
According
to the 2004 Draft EIR,
the bridge would not result in a sufficient improvement in service
level to justify it as a stand-alone project. Genesee widening would
result in an acceptable level of service on virtually all road segments
in the study area. The underpass (grade separation) is projected
to result in poor segment LOS.
In
the context of the current study, however, segment LOS is of dubious
utility. A more relevant figure of merit is the intersection
level of service, which is based on average delay times
incurred by peak hour drivers at a given intersection. It is the
intersection operation that largely determines the flow of traffic
along a corridor during peak hours.
Our
point system: The base 2030 "no project" service levels
are assigned a combined score of zero. Alternatives score 0.5 points
for each half-grade of service level improvement up to a maximum
of 2.5 points. Thus, improvement from F to D is worth 2 points,from
F to anything better than D is 2.5 points. For example, on the six
segments listed below, the Genesee widening alternative picks up
0.0 (CD to CD), -0.5 (C to CD), 2.5 (F to CD), 2.5 (F to CD), 2.5
(F to CD), and 2.5 (F to C) points for a total of 9.5 points.
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