This paper informs Members of progress on the Feasibility Study on Electronic Road Pricing (ERP).


2. In November 1994, the Working Party on Measures to Address Traffic Congestion published a report which recommended, inter alia, the commissioning of a technical consultancy to examine the feasibility of an ERP system in Hong Kong, a system based on the adoption of the "user pays" principle as a long term solution to the traffic congestion problem.


3. On 7 June 1996, the Finance Committee approved the funding of $90 million for the feasibility study. The objective of the Study is to examine thoroughly the need, feasibility and effectiveness of introducing ERP in Hong Kong.

4. After a competitive process, an international consultancy led by Wilbur Smith Associates and Hyder Consulting was commissioned to conduct the study. The study will last 27 months. Work started on 10 March 1997 and is expected to be completed in June 1999. The scope of work includes -

  1. developing a transport model;

  2. evaluating ERP strategies;

  3. identifying and evaluating alternative technology options;

  4. carrying out field evaluations;

  5. undertaking a conceptual system design;

  6. carrying out public consultation; and

  7. refining the preferred strategy.

5. An outline of the major elements of the study is in Annex A.


6. The Consultants have developed an ERP Transport Model with the aid of results from stated preference surveys. On the technology side, two preferred technology options have been identified and tenders for the field trial of them have been invited.

7. The current status of the major activities are as follows -


Scheduled Completion Date

Current Status

(a) stated preference surveys and development of transport model

late 1997


(b) evaluation of technology options

late 1997


(c) field evaluation of technology options

late 1998

tenders being assessed

(d) formulation and evaluation of ERP strategies

late 1998


(e) conceptual design of ERP system

early 1999


(f) public consultation

early 1999


(g) final ERP strategy

late 1999


Stated Preference Surveys

8. Stated preference (SP) surveys were conducted in May 1997 to gather information on individuals' likely responses to a range of alternative ERP scenarios. 1,344 respondents completed the interviews. The following table summarises the estimated responses by motorists, based on results of the surveys, to a hypothetical ERP system involving a $20 charge to cross each of four screenlines (Kowloon External, C-C, Hong Kong Internal around Central, and Hong Kong External) in the AM and PM peak periods*.


Shift to Public Transport

Time Shift

Change to Park & Ride

Change in Occupancy

Trip Suppression



















* Only those trips directly affected by the assumed ERP charge (40% of all trips) are included in the table. The screenlines are illustrated in Annex B.

9. The table shows that during the peak periods 13 to 15% of motorists would switch to public transport and 24 to 27% would change the time of their trip to avoid paying the ERP charge.

Transport Model

10. The Study Team has developed a transport model to assess traffic conditions and the performance of the future road network with and without ERP. It is able to model the impact of ERP on traffic behaviour such as changes in transport mode, route, timing, destination, occupancy and demand. It is able to test the impact of alternative scenarios concerning -

  1. area to be covered by ERP;

  2. charging mechanism which can be based on distance, time, area or congestion level;

  3. types of vehicle to be charged;

  4. variations of charge by time period;

  5. complementary measures, such as park-and-ride and public transport priority schemes; and

  6. availability of alternative routes.

The output of the model will also be used for assessing environmental impact of various ERP schemes.

Initial ERP Strategies

11. The need for ERP is currently being studied. It is anticipated that some initial strategy concepts would be formulated and alternatives to ERP would be evaluated in the coming three months.

Preferred Technology Options

12. The Study Team has recommended two preferred technology options.

  1. Dedicated Short Range Communication (DSRC) system - In this system each vehicle is equipped with an In-Vehicle Unit (IVU) or a transponder fixed to the windscreen. The unit can communicate with the roadside readers by microwave transmission similar to the existing autotoll systems at the tunnels. Both smartcard based IVUs (suitable for protecting privacy) and read-write transponder (suitable for central accounting) will be tested. Having been developed for some years, the technology is relatively mature. It was used in Highway 407 in Canada and will be used in the Singapore ERP system to be commissioned later this year. However its major disadvantage is the requirement of massive gantries at each charging point to install the overhead equipment. This will be costly and also physically very difficult in the urban built-up areas.

  2. Vehicle Positioning System (VPS) - In this system each vehicle is equipped with an IVU which can determine its position by receiving special signals transmitted from satellites in the sky or fixed stations at different locations throughout the territory. When the IVU determines that the vehicle has entered a pre-defined charging zone, the associated charge will be deducted from a smartcard inserted into the device by the driver or from a registered account in the central control centre. Unlike the DSRC system, no gantries will be required for installating roadside equipment for transaction purposes. However, there will still be need for fixed enforcement equipment at strategic locations supplemented by portable stations. The technology is recent and has not been fully tested for ERP application. The major concerns will be the effectiveness of the enforcement sub-system and the accuracy of vehicle positioning, since tall buildings in the urban areas may obstruct satellite signals.

Field Evaluation of Technology Options

13. The purpose of the field evaluation will assess if the technology options can correctly impose charges, classify vehicles and detect and record violators in a multi-lane unchannelised traffic situation with vehicle speeds varying from start and stop to high speeds.

14. Field evaluation of the selected technology options will be conducted under two separate contracts. Tender submission was closed on 20 February 1998. Two tenders for DSRC and three for VPS were received and are being assessed. According to the current schedule, the two contracts will be awarded in May 1998.

  1. Both options will be extensively tested at off-street and on-street test sites. Off-street tests under controlled environment will be conducted on part of the runway at Kai Tak after its de-commissioning. On-street tests under normal traffic conditions for the DSRC system will be conducted in Wanchai and Causeway Bay. The sites are selected because existing flyovers and footbridges can be used to mount the roadside equipment. On-street testing zones for the VPS will be extended to cover most of the urban areas to test its performance under various geographical and physical conditions. Annexes C to E showing the off-street test site, the location of on-street sites and drive circuit, and VPS test zones respectively are attached.

  2. The contract period will be 12 months from August 1998 to July 1999. All off-street and on-street tests will be completed in the first six months. The contractors will continue to provide data analysis support in the last six months.

  3. IVUs will be fixed to a variety of vehicles including cars, vans, buses, goods vehicles and motorcycles. The fleet of vehicles will be provided by both the contractors and the Government and will be driven around the test sites according to pre-defined routes.

  4. The contractors are encouraged to propose additional features in the ERP system to demonstrate the capability of the system to integrate with Intelligent Transport Systems.

15. Concurrent with the field trials of the preferred technology options, the Study team will proceed to formulate and evaluate ERP strategies. This part of the Study is expected to be completed by late 1998.

Transport Bureau
March 1998
[TBCR 1/2061/89(97) Pt.8]