Civil Engineering Reference
In-Depth Information
Table 5.1 CBD size and employment in selected cities
Area
Total city
population,
2000
Total
downtown
commuters,
2000
Total transit
commuters to
downtown,
2000
Downtown
land area
(square
wiles)
Transit share
of downtown
commuters
(%)
Worker
density
(commuters
per square
mile)
New York
8,008,278
379,380
290,390
1.08
76.5
351,277.80
Chicago
2,869,016
341,014
210,490
1.13
61.7
301,782.30
Son Francisco
776,733
320,170
156,764
2.55
49.0
125,556.90
Washington, DC
572,059
409,505
154,658
3.99
37.8
102,632.80
Boston
589,141
570,315
137,701
2.32
50.9
116,515.10
Philadelphia
1,517,550
230,358
105,387
2.40
45.7
95,982.50
Seattle
563,374
147,905
54,435
2.99
36.8
49,466.60
Los Angeles
3,694,820
215,340
43,656
3.78
20.3
56,968.30
Portland
529,121
104,810
28,839
2.11
27.5
49,673.00
Houston
1,953,631
155,050
25,874
1.68
16.7
92,291.70
Dallas
1,188,580
91,786
12,493
0.85
13.6
107,983.50
Son Diego
1,223,400
75,850
8,675
2.16
11.4
35,115.70
Sacramento
407,018
64,830
7,959
1.26
12.3
51,452.40
Son Antonio
1,144,646
53,440
3,842
1.15
7.2
46,469.60
Austin
656,562
76,150
2,913
0.95
3.8
80,1 57.90
Note
Selected cities with total population 600,000+
Ranked by number of transit commuters to downtown
Source
Reference [
1
]
one to two square miles and has the highest employment densities in the urbanized
area. Salient characteristics of selected city centers are shown Table
5.1
.
As employment and employment densities increase, there is generally an
increase in the public transportation share of commuters. However as employment
densities increase, there is also an increase in automobile and pedestrian trips. This
tends to overload traf
c on the road network making congestion a recurring event
during rush hours.
Central business district growth has varied over the years. Economic conditions,
efforts to revitalize the center, and availability of good highway and public transit
access have been essential in the revitalization of mature centers. As shown in
Table
5.2
, this growth [
2
] has generally been modest in most cities (however, any
growth will increase congestion unless public and private transport capacity is
increased).
5.2.2 Outlying Mega-Centers
Over time many of the metro region jobs, shopping and entertainment opportunities
have moved closer to their suburban customers at locations near freeway inter-
changes that are easily accessible by car. The popularity of these suburban
