Geoscience Reference
In-Depth Information
have a negative impact in terms of increasing VKT and VHT in the outskirts of the
metropolitan area. However, this effect might not be so negative as far as ambient
air pollution is concerned, since the emissions would spread out over a larger area.
It should be noted, however, that the emissions in problematic, denser areas, such as
the Tel Aviv CBD, would decrease.
21.4.2 Increasing Parking Fees
In contrast to the previous case, the demand for travel in this scenario is assumed to
be elastic. Travel demand for the origin-destination (O-D) matrix is dependent on
the rate of parking fees. As indicated in the methodology section, we applied the
elasticity Eq.
21.1
to different parking fees and search times. In all tests, the same
network as in the base case was used. The difference between each scenario is,
again, due to the change in the O-D matrix. The results for parking-search time are
quite similar to those for parking fees; therefore, they are not presented here.
The results obtained are quite interesting: part of the trends are linear; the CBD
and inner ring super zones have less VKT, number of trips, and travel time with the
parking-policy fee scenarios than with the base scenario. The outer rings have more
VKT, number of trips, and travel time with the fee scenarios than with the base
scenario.
Selected results are presented in Figs.
21.3
,
21.4
, and
21.5
. The results shown are
for the overall metropolitan area, the Tel Aviv CBD, and the outer ring (Netanya)
super zone. Each figure displays the percentage change for each scenario compared
to the base scenario with respect to three variables: VKT, VHT, and total number of
trips.
Figure
21.3
shows that a small increase in parking fee will lead to an increase in
the total time traveled. This result is explained by the fact that the model takes into
account the combined effect of increasing parking fees: on the one hand, the total
demand for travel decreases; on the other hand, parking search time increases,
leading to an increase in the overall travel time.
An additional important finding is shown in Fig.
21.3
. For a certain substantial
increase in parking fees, total VHT decreases compared to the base scenario. In the
case of the metropolitan area, this value is around 75 %; in other words, parking
fees must almost double before there is a drop in total VHT. This point is important,
since it represents the point at which the increase in parking fees results in a
decrease of both VKT and VHT at the metropolitan level.
Figure
21.4
shows the results for the Tel-Aviv (CBD) super zone. We can
observe a linear decrease in all three variables as parking cost increases. There is
a steep decrease in VKT, apparently proportional to the decrease in the number of
trips. In contrast, the decrease in travel time is very mild. Since the parking supply
and parking fee affect mainly zones within the city itself, all three variables have
values that are less than those of the base scenario, even when the parking cost is
raised by only 10 %.
