1. Atkins’ TIF Studies
Graham Bown

2. Introduction Based on experience of Cambridge TIF and Bristol TIF
25/04/2019
Atkins' TIF Studies
Introduction
Based on experience of Cambridge TIF and Bristol TIF
General modelling discussion plus SATURN based experience:
Data
Segmentation
Guidance
Charging schemes
Practical issues
Appraisal

3. Data Roadside data not previously collected with income ranges
25/04/2019
Atkins' TIF Studies
Data
Roadside data not previously collected with income ranges
Data collection needs to consider complementary measures
The risk of collecting insufficient evidence to support a different hierarchy from the WEBTAG default is considerable

4. 25/04/2019
Atkins' TIF Studies
Segmentation
TIF specified income and purpose segmentation leads to larger number of user classes
There is requirement to show validation of segmented base year

5. Guidance Very comprehensive (demand and local models)
25/04/2019
Atkins' TIF Studies
Guidance
Hierarchy structure in WEBTAG related to major urban conurbations
Freestanding mono-centric sub-region may be different
Very comprehensive (demand and local models)
Although most is still at the consultation stage
“It is clear that the more advanced parts of the guidance have not yet been used by scheme promoters designing road pricing schemes” (DfT, WebTAG Consultation Documents page)

6. Guidance MECC / MSC Provides theoretical optimisation calculation
25/04/2019
Atkins' TIF Studies
Guidance
MECC / MSC
Provides theoretical optimisation calculation
Of limited practical use to politicians or for objective setting
May be a useful measure of efficiency against theoretical optimum

7. Charging schemes Link based Cordon
25/04/2019
Atkins' TIF Studies
Charging schemes
Link based
Cordon
Point of use cordon type charges are easy to model
Area licence systems
Need to consider
Trip chaining
Use of ring road / bypass – multi-charge
Discounts
Study areas for area wide charging schemes may need to be very large

8. Practical Issues for Charging
25/04/2019
Atkins' TIF Studies
Practical Issues for Charging
Matrix or network based?
Through trips and trip chains
Remember tolls in SATURN are per pcu not per vehicle or person!
For simplicity it will be desirable to code tolls as money costs
Use of $INCLUD files for tolls will facilitate easy testing of alternative toll regimes/levels with the same network file.

9. Appraisal Business model: Declaration - low frequency users
25/04/2019
Atkins' TIF Studies
Appraisal
Business model:
Declaration - low frequency users
Express Declaration (with registration)
Fleets - organisations with more then 10 vehicles using the scheme
Disabled Persons or Zero VED based exemption
Enforcement
Residents discount registration fees
Toll skims

10. Wider Picture Scheme optimisation Complementary measures Alternatives
25/04/2019
Atkins' TIF Studies
Wider Picture
Scheme optimisation
Complementary measures
Alternatives
“Big ticket” items
Smarter choices
Solutions to problems on toll boundary
Social inclusion and equity

11. Thoughts Onerous – a lot of data, modelling and requirements
25/04/2019
Atkins' TIF Studies
Thoughts
Onerous – a lot of data, modelling and requirements
Challenging – cutting edge, complex, tight deadlines
Interesting – theoretical, practical, political