Civil Engineering Reference
In-Depth Information
Table 16.2 Congestion management strategies for using existing capacity more ef
ciently
—
summary of effectiveness and implementation potential
Type of improvement
%
Increase
in speed
% Decrease
in travel
time
%
Decrease
in delay
%
Decrease
in stops
Source
Improved timing
0
-
5
-
-
-
(A)
Coordinating isolated signals
2
25
(A)
-
-
-
-
Placing isolated signals on
computerized system
30
(A)
-
-
-
Placing single dial system on
computerized system
15
-
20
-
-
-
(A)(B)
Placing multiple programmed
signals on computerized system
6
-
10
-
-
-
(A)(B)
California statewide program
15
7
15
10
(A)
Texas statewide program
19
9
(A)
-
-
Notes
(A) Reference [
7
]
(B) Reference [
8
]
Estimates are adapted in part from: Rowan, N.S., Woods, J.P., Stover, V
(a) Alternatives for improving urban transportation
—
a management
Overview Prepared for FHWA by TTI, Taxes A&M University, 1977
(b) Technical Memorandum 3, Quantifying Measures of Effectiveness, Tri-State TSM Study,
Wilbur Smith and Associates, 1978.
Source
Reference [
9
]
16.4.8 Reported Time Savings
Reported travel time savings resulting from traf
c signal timing improvements,
operational treatments along arterial streets, and improved freeway operations are
shown in Tables
16.2
and
16.3
, respectively. These tables, assembled from various
sources, provide a basis for estimating travel time savings from similar congestion
reduction treatment elsewhere.
16.5 Curb Parking and Loading Zone Management
On-street parking and loading zones are found throughout the metropolitan area.
Curb parking and loading/unloading activities are usually concentrated in older
commercial districts and in densely populated residential areas where there is
limited off-street parking space available.
On-street parking or standing along major streets often takes away street space
that could be used for the movement of motor vehicles. These events frequently
create congestion especially during the peak travel times and sometimes throughout
the day. A short stretch of curb parking can reduce the capacity of an entire street.
