Archive:Hong Kong Mass Transport Study/Chapter 5

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Chapter 4 — Planning Characteristics and Projections

Hong Kong Mass Transport Study, Chapter 5 Travel Characteristics and Projections

Chapter 6 — Recommended System

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TRAVEL CHARACTERISTICS AND PROJECTIONS

1. A superficial inspection might give the impression that urban traffic movement is entirely random in character. However, consistencies are revealed when large numbers of journeys are reduced to such basic components as trip purpose, travel mode and trip length. All movement expresses the social and economic activities of the community and, once the relationship between travel and these activities is established, a mathematical evaluation of traffic flow can be made. Existing travel patterns in Hong Kong have been analysed intensively to derive these mathematical relationships.

HOME-INTERVIEW SURVEY

2. Two complete home-interview surveys were conducted by the Passenger Transport Survey Unit. One was based on a selective sample of households obtained from Government building and housing records. The other was based on a sample of car and motor cycle-owning households, taken from motor vehicle registration data. A total of 7,853 households was included in the former and 4,161 in the latter. The car-owning households included in the building-unit survey were later removed, to avoid duplication when the data from the two surveys were combined.
3. The home-interview survey data provided most of the in formation upon which this Study is based. A great deal of information about household characteristics, in addition to travel information concerning the members of the households, was gathered.
4. The Passenger Transport Survey Unit applied the initial expansions to the basic data. Additional expansions, adjustments and corrections were then made based on comparisons with other data, including all cross-harbour travel as measured in the ferry surveys. Analysis began after comparison with known full-scale data revealed sufficient correlation to proceed with confidence.

TRIP GENERATION (HOME-BASED)

5. Trip Generation is a term used to describe the number of journeys starting or ending in a zone, in relation to its social and economic characteristics. A study of trip generation does not attempt to cover all the characteristics of trips—direction, length, duration, etc.—but simply to quantify and classify the trip-ends in each zone.
6. Since home-based trips constitute more than 80 per cent of the total and can be related to household characteristics, they are analysed separately from those which are non-home-based. The home-based trip generations from the expanded home-interview survey were stratified according to trip purpose and related to various categories of households. Many categories were considered before settling on house type, car ownership, and family income as the variables to be used. The generations were converted to trip rates per person, as summarized in Tables 38, 39 and 40.
7. The actual trip rates used in the survey were different for each of the 10 primary traffic zones, and those presented in the tables are the Colony averages. The trip rates for squatter households were also produced as part of the process, but since it is assumed that all squatter households will have been relocated in permanent housing by the design year (1986), they are not included as a separate category. The trip rates used in the projections were for total transport, and the public transport portion was obtained from the modal split process described later in this chapter. However, for comparative purposes, Table 41 shows the public transport trips and the trip rates per household as obtained from the home-interview survey. It should be noted that the term "trip" as used in this chapter refers to the entire journey from origin to destination regardless of the number of modes used. Therefore, the totals quoted herein for the base year do not compare with the totals derived from the records of the public transport companies. Public transport and total trip generations, and generations per household are tabulated in the appendix of this report.
8. New Territories Travel — As the home-interview survey was only conducted within the urban area, it was necessary to synthetically calculate data for the New Territories. As primary Zone 8 is the urban area most closely resembling the New Territories, having some concentrations of urban development though primarily rural, the trip generation rates obtained in this zone were used to represent conditions in the New Territories. A completely independent analysis of New Territories travel was also made based on survey information gathered there as part of this Study. A comparison of the results obtained by these two methods revealed very similar trip patterns. (Overall, the independent analysis resulted in 5 per cent more trips; but in the largest zone, Tsuen Wan, it was within 3.6 per cent.) Therefore, the simulated New Territories data based on primary Zone 8 were used for the projections, as they provide more detailed information that can be of value later.

TRIP ATTRACTION (HOME-BASED)

9. An analysis of the various attracting influences exercised by different activities throughout an area becomes quite complex due to their interaction. A person about to make a trip is influenced by many different considerations in his choice of destination. The location cf available jobs, shopping centres, schools, recreational facilities and other activities, largely determines the number of trips attracted to the various zones. Therefore, trip attraction has been developed by regression analysis, using the parameters available for each zone. The best correlation between trip attractions and planning parameters was found in the following equations:

$\begin{array}{l}\text{Attractions from Car-owning Households}\\ =0.416X_1+24.522X_2-37.036& \text{for Manual Work Trips}\\ =2.381X_3-156.276& \text{for Non-manual Work Trips}\\ =1.379X_4+0.070X_5+0.389X_6-218.954& \text{for Other Home-based Trips}\\ \text{Attractions from Non-car-owning Households}\\ =1.392X_7-663.386& \text{for Manual Work Trips}\\ =2.403X_8-1,561.602& \text{for Non-manual Work Trips}\\ =4.235X_4+2.723X_5+0.860X_6-478.547& \text{for Other Home-based Trips}\end{array}$$\begin{array}{l}\text{where:}\\ X_1=\text{Number of manual employees who are residents of households with cars}\\ X_2=\text{Attraction index (attraction rating for each zone)}\\ X_3=\text{Number of non-manual employees who are residents of households with cars}\\ X_4=\text{Cars available}\\ X_5=\text{Retail employment}\\ X_6=\text{Other employment}\\ X_7=\text{Number of manual employees who are residents of households without cars}\\ X_8=\text{Number of non-manual employees who are residents of households without cars}\end{array}$

10. To provide an additional parameter for use in this analysis, each zone was rated with an attraction index number based on the amount of activity in each zone. This parameter was found to be significant in the attraction of manual work trips. Public transport and total attractions by sectors are tabulated in the appendix along with the subjective attraction points for each zone in the base and design years.

NON-HOME-BASED TRIPS

11. Non-home-based trips, like attractions, cannot logically be equated to household characteristics. The factors that motivate this type of trip are varied and complex. Therefore, these trips were developed by regression analysis, and non-home-based origins and destinations were found to correlate with the number of total home-based trip attractions. The following equations were used:

$$\begin{gathered} \begin{array}{l}\text{Non-home-based trip origins} \\ =\\ 0.220 \\ \text{home-based attractions}-390.368\\ \text{Non-home-based trip destinations} \\ =\\ 0.232 \\ \text{home-based attractions}-726.831\end{array} \end{gathered}$$

SCHOOL TRIPS

12. The Passenger Transport Survey Unit made a separate school survey during the school term, since the home-interview survey was conducted in the summer months when many schools were not in session. The school information obtained in the home-interview survey was therefore removed and a separate analysis was made of the school survey information.
13. The number of school trips in the base year was related to the number of resident students and the school enrolment in each zone. Public transport school trips were projected to the design year based on the resultant equations but the appropriate constants were reduced to produce a smaller proportion by public transport. Overall there was a 28.6 per cent reduction. This was done in recognition of the efforts being made to improve the accessibility of schools in the Colony. This will make it possible for a higher proportion of students to attend school in their own neighbourhood and will thus increase the proportion who walk to school. Table 42 shows the present proportion of school trips by the various modes of travel. School trip data for the base and design years are included in the appendix tables of trip generations and attractions by sector and purpose.

TRIP-END PROJECTIONS

14. The trip rates and regression equations, developed from analyses of travel data for the base year, were applied to the design-year (1986) household categories and planning parameters. This was done to obtain the trip-ends for the design year and is based on the premise that, on an average, the members of households with certain social and economic characteristics will have certain travel habits. In the future the number and distribution of house holds in any given category may change and individual families may move from one category to another but the basic relationship between travel and other characteristics remains the same for each household category.
15. Table 43 is a summary of the total design-year trip-ends according to purpose and geographic area. More detailed tables are included in the appendix.

TRANSPORT SYSTEMS ASSUMED FOR TESTING

16. Up to this point the analysis has only concerned the total number of trip-ends in and out of each zone. No consideration has been given to the mode of travel nor to the length and direction of trips. To take these into account it was necessary to relate the travel to a specific network, or networks. Three complete design-year public transport systems were devised to fill this need and to provide the basis for the study of alternatives. Each of these conceptual systems was sufficiently different from the others to provide information on a wide variety of public transport services and give a clear indication of the value of each. However, all the systems were designed to serve the same living, industrial and commercial areas, so the principal variation was in the type and level of public transport service offered.
17. Since future travel volumes were not known at the time the test systems were devised, it was necessary to anticipate the public transport service that would be needed. To arrive at the system required, hypothetical systems were designed which were above and below estimated needs. The first system tested consisted primarily of improvements and extensions to the existing surface public transport system with no rapid-transit elements. The third system included extensive rapid transit supplemented by bus, train and ferry services. The second system fell between these two, including a smaller proportion of rapid transit and relying more on surface vehicles.
18. All of these systems were converted to coded network form for traffic assignment by computer. The network speeds were based on detailed travel-time studies of existing public transport movements, modified to reflect expected street improvements and growing traffic congestion. The rapid-transit speeds were computed from station spacing and the performance characteristics of modern equipment. Walking, waiting and transfer times were based on field surveys in some instances and on an analysis of anticipated conditions in others.
19. System 1 — This system was designed to test whether the capacity requirements of future urban travel could be met, with minimum capital expenditure, by expanding the existing public transport system of buses, trams, ferries and the passenger services of the Kowloon-Canton Railway. Even this minimum-cost system would require large capital expenditures for additional vehicles and for the replacement of existing ones. The main components of this system are shown in Figure 24 and briefly described below.
20. The majority of passenger movements would continue to be accommodated by ordinary surface bus lines, expanded in coverage and capacity to meet increased future travel. To reduce the travel times of longer distance journeys, local buses would be supplemented by limited-stop or express bus lines on major thoroughfares. Many street improvements would need to be made to facilitate the movement of buses if this plan were adopted. Several bus terminals were included to provide off-street loading facilities and to facilitate transfers between express and local services.
21. Major improvements in the tramway service included relocating the portion of the line through the Central District, between the Naval Dockyard and the Western Market, into an underground tunnel. This would require re-equipping the operation with single-decked cars of either articulated or multiple-unit type. Improvements would also include extending the tram line to Chai Wan and changes in the Wan Chai area to increase the speed of tram operation. The portion of the line that now runs on Johnston Road would be relocated to Hennessy Road, to eliminate the need for trams to turn across the Hennessy Road traffic at each end.
22. The cross-harbour and outlying area ferries would continue to form vital links in the transport system and in many instances would have to be expanded to meet new demands. All existing cross-harbour ferry routes would be retained except the Hung Hom—Edinburgh Place and Hung Hom—Wan Chai lines, which it was assumed would be replaced by buses using the cross-harbour tunnel. A hovercraft ferry, operating between the Western District of Hong Kong Island and Castle Peak, was also included as part of this system, supplementing an express bus operating to Castle Peak from Kowloon.
23. The Kowloon-Canton Railway was assumed to be double-tracked to Sha Tin to provide added passenger capacity to this future New Town. Access to the existing Yau Ma Tei Station would need to be improved to provide for transfer with buses, and for better pedestrian connection with Mong Kok. A bus-railway transfer station was also included at the new Hung Hom railway station. Individually powered diesel passenger cars operating between Hung Hom and Sha Tin were envisaged as a major component of this system.
24. System 2 — This system was designed to provide a basic high-capacity rapid-transit service in the main travel corridors, including the cross-harbour movement; it also allowed for a complete network of surface bus transport for those areas and short trips not accommodated by rapid transit. This system is shown in Figure 25. The rapid transit was envisaged as predominantly an overhead system, but with underground segments at least through the Central and Western Districts on the Island, across the harbour and extending approximately one mile north in the Nathan Road corridor of Kowloon. There was rapid transit within the extended urban area, including Kwun Tong, Tsuen Wan and Sha Tin, with direct connection to express and local buses running to suburban communities.
25. The Kowloon-Canton Railway was assumed to be electrified to Sha Tin and equipped with rapid-transit type vehicles to make it an integral part of the urban system. It was tested as a double-track system from Hung Hom to Sha Tin, including the tunnel north of Kowloon. It was assumed that all goods movements would be accommodated in the late night and early morning hours to avoid interference with day-time passenger services. A new station was included in Kowloon Tong to provide direct connection with other parts of the rapid-transit system. The overall length of the rapid-transit lines, including the Kowloon-Canton Railway section, was 33 miles and there were 45 stations. A few cross-harbour ferry routes were included to supplement the cross-harbour bus and rapid-transit services. A hovercraft ferry operating between the western part of Hong Kong Island and Castle Peak was also included.
26. System 3 — This system assumed maximum development of rapid-transit routes and is shown in Figures 26 and 27. It was designed to divert as many trips as possible from surface buses and trams, as well as from automobiles and taxis, and to accommodate these trips efficiently. It would provide direct rapid-transit service to Junk Bay, Kwun Tong, Sha Tin, Tai Po, Tsuen Wan, Castle Peak and Aberdeen. It included two rapid-transit harbour crossings. The overall length of the rapid-transit system would be 70 miles and there would be 68 stations.
27. The improvements to the Kowloon-Canton Railway would be similar to those for System 2, except that an additional connection between the railway and the urban rapid-transit system would be provided at the new Hung Hom railway terminus. In this system, electrification and double tracking was extended to Tai Po.
28. There would be a network of local surface buses operating for the short trips and in areas not close to rapid-transit stations. It is doubtful whether passenger ferry service within the harbour could be sustained with this system. However, the ferry services to the outer islands would have to continue and there might still be a need for vehicular ferries to supplement the cross-harbour vehicle tunnel. A hovercraft service from Kennedy Town to Castle Peak was also included in the network.
29. Trams were not specifically included in Systems 2 and 3. However, the assignment of volumes to the many bus lines included along the north side of the Island, provides an estimate of the total movement by surface transport, regardless of the type of vehicle.

• Figure 24 — Test System One
  Figure 24 — Test System One
• Figure 25 — Test System Two
  Figure 25 — Test System Two
• Figure 26 — Test System Three
  Figure 26 — Test System Three
• Figure 27 — Test System Three - New Territories
  Figure 27 — Test System Three - New Territories