On the impact of fast route geometry in London with some strategic applications

1. On the impact of fast route geometry in London with some strategic applications Les Mayhew Cass Business School International Geographical Union (IGU) conference Leeds University, 2013 lesmayhew@googlemail.com

2. Geographical theory and urban analogues Classical geographical theory • Central place theory, hierarchies, economic efficiency, spatial equilibrium, accessibility • Optimum location of the firm, market areas, competition • Minimisation of production, distribution, and environmental costs • Travelling salesman involving delivery systems, problems involving minimisation of travel costs • Network assignment problems, queuing theory, modal split, shortest paths Urban analogues • Retail centres, health care facility location, administrative centres • Airport and railway hubs, out of town retail centres, river crossings • Assembly systems, warehousing, delivery systems (e.g. parcels, food) • Emergency response systems (police, fire, ambulance) • Road charging, traffic management, air quality • Strategic planning and public policy (housing, employment and public transport) • Green Belt and parks

3. Challenges and tools • Spatial representation and mapping of urban areas – concentric, multi-centred, coastal, estuarine • Urban metrics – not undifferentiated planes but a more complex geometry (e.g. networks, non-Euclidean, or other geometry) • How to integrate spatial decision making with economic aspects viz. generalised costs of travel, cost-benefit analysis • Spatial and mathematical tools which should be simple to understand, general and abstract from reality i.e. based universal principles and transparent assumptions

4. Structure • Urban spatial metrics and key spatial concepts – a refresher • Introduction to properties of orbital radial metrics • Overview of applications including congestion charging, airport location, river crossings and urban structure • Concluding remarks

5. Travel within urban areas: Alternative metrics Euclidean travel in undifferentiated plane Time-Cost minimisation (non-Euclidean) Cartesian (‘Manhattan’ metric) Double radial metric Orbital – radial metric

6. Basic geometric conceptsAreas and isochrones t Isochrones and shortest paths Route catchments Market areas Regular tessellated market areas

7. Fundamental time surfaces Time surfaces are 3-D representations on which distance equates to travel time. Distance is measured in minutes or hours and areas in square minutes or hours. Patterns on time surfaces such as tessellated market areas can be transformed to the urban plane and their properties studied. Fundamental surfaces include the cylinder, cone, sphere and plane Source: Hyman and Mayhew 1984

8. Tessellated urban planes based on different underlying time surfaces These tessellations are generated from 3-D time surfaces and show the intricacies of tessellated patterns achievable. In these cases average travel speeds increase with distance from the city centre. Every market area however has the same travel time radius, the sizes of which are a function of local travel speeds and road configuration.

9. Example: 10-minute isochrones around A&E centres Map based on access to local A&E centres in London. Around each centre is drawn a 10-minute isochrone. The isochrones do not tessellate as in the time surfaces but in the real world we can always expect imperfection. With GPS systems and data extractable from systems such as Google Map the data exist to calibrate such maps with considerable accuracy. Local movement constricted by local road configuration and traffic density. Movement in outer areas less constricted and so fewer centres are needed This map is based on average speeds increasing according to

10. Route catchments and isochronesConcentric city with radial and orbital movement isochrones route catchment quickest paths

11. Urban orbital-radial metric in concentric cities Travel time via centre Travel time via ring R = ring radius VA= radial speed R1= fixed trip end VB=orbital speed R2= variable trip end k=VA/VB =angle between R1 and R2

12. Test of orbital efficiency destination destination Orbital and radial route catchments based on an exterior destination north of the city centre destination located outside the orbital

13. Congestion charging • Introduced in London in 2003 • It covers an area of about 3km in radius • It aims to reduce congestion and raise funds for London's transport system • It costs £10 a day between 7:00 and 18:00 on weekdays

14. Spatial impact of central congestion charging on route catchments in a 3-ringed city Maps demonstrating the power of congestion charging to re-direct traffic and the need to measure effects over a wide area. Route catchments are based on four routing options consisting of three orbital routes and radial travel Route catchment maps for two fixed locations: (A) At 7.5 kms, no charge; (B) At 18.5 kms, no charge; (C) At 7.5 kms, charge applied; (D) At 18.5 kms, charge applied

15. Strategic river crossings – building a new bridge in east London Possible routes 1. Double radial (via city centre) 2. Inner ring clockwise 3. Inner ring anti clockwise 4. Outer ring clockwise 5. Outer ring anti -clockwise River Thames Key to notation ‘k’ are river crossing points Charges are applied at k1 and k2; k4 and k5 are toll free A congestion charge is applied to journeys passing through the central charging zone (k3) Costs based on monetised travel time plus toll or congestion charge

16. Images of strategic crossing points in east London free £2.00 Inner ring – Woolwich ferry Outer ring – Dartford crossing ? £3.20 Inner ring bridge design New cable car crossing Central London congestion charge £10

17. Total market capture of old and new river crossing Different locations have different route market shares. Contour values at any given location represent the percentage of traffic using a particular route. The higher the market share the busier the route is expected to be at that location and the greater its influence over traffic at any point Outer ring radius 25kms Inner ring radius 12.5 kms

18. Should London build a new airport in the Thames Estuary? Artist’s impression of new airport and its proposed location in the Thames estuary about 66 kms from the city centre

19. Radial market area, A Orbital market area B Orbital market area A Ring road Two airports A,B with slow orbital road Two airports A,B with fast orbital road Two attraction problem in an orbital-radial urban area: Example of two airports

20. Internal The concept of eclipsed market areas and their importance in locating new airports External External and Internal Eclipsed Regions for attraction A Map showing inner and outer eclipse envelopes for a 3-attraction example. Shaded areas are eclipsed The market area of any proposed new airport which is located in the shaded region of either map would be eclipsed by existing airports

21. Radial market area Introduction of new airport in east London but will it be ‘eclipsed’ before it is built? A location on the east side of London makes strategic sense and would be a good strategic fit with the other regional airports Locations and market areas for four and five regional airports. The circle represents the M25 orbital route. Inner and outer eclipse envelopes are also shown (A = Heathrow; B = Luton; C = Stansted; D= Gatwick)

22. But is the proposed location viable? Chart shows how the market share of existing airports adjust according to the distance of the location of the new airport from the city centre. The new airport would capture nearly 30% of the geographical market if it located at or near the M25 but this would reduce zero if it were twice this distance from the centre (proposed location is 66kms from the city centre)

23. Outside boundary Trips divert through centre Inside boundary Orbitals Market areas in orbital radial networks (a) (b) Service area enclosed by isochrone situated on a fast orbital – two cases. The area enclosed by the isochrone in case (a) is given by:

24. Tessellating concentric urban areas with multiple ring roads • Tessellated concentric hypothetical urban areas with one to five rings and six facilities per ring: • 12.5kms gap between rings • Radial velocity 50 kph • Maximum travel time radius to nearest centre is 15 minutes • Orbital travel time 3 hours • Ring speeds proportional to distance from city centre • Inner ring service area 164 sq km; out ring 818 sq km • Six facilities per ring

25. Areas spanned in given travel time radius ‘All-purpose speed’ in interstitial areas (a) 50kph (b) 25kph (c) 10kph Where there are a finite number of fast radial routes it may be useful to distinguish between speeds achievable on the fast routes from the interstitial ‘all-purpose’ routes

26. E B A D C Abercombie Greater London Plan (1944) Arterial (motorway standard) Sub-arterial major roads Basic standard (A) (B) (C) (A) Abercrombie’s arterial system; (B) ‘Tessellated version of Abercrombie; (C) tessellated version with slower interstitial road speeds. There are ten fast radials with 5 orbital-radial intersections on each ring

27. Does Abercrombie’s ring structure work? • Ring B the ‘inner ring’ is of ‘merit’ as is ring D, both of which are designated motorway standard • The outer-most ring E could be of merit but it was not designated motorway standard in the plan • Ring C, the current N&S circular is not of merit but should be • Ring A corresponds almost exactly to the current central area congestion charging zone and has assumed much greater importance • The analysis also suggests the need for a ring ‘O’ which would be of approximately 1-2kms radius inside the current congestion charging zone and pedestrianised. This has been included in the previous slide

28. Comparison with today • The London orbital M25 combines features of Abercrombie’s two outer rings D and E • Ring A corresponds with the London congestion charging Zone • Ring B the inner motorway ring was abandoned in the 1970s • Ring C the N&S Circular has been improved in parts but does not join up • Ring E exists but is not fully joined up and is not considered ‘strategic’ • A few radials of motorway standard have been constructed but most terminate at or around the M25 orbital instead of ring B as envisaged

29. What’s changed and why was plan not completed? • Conflict between high street retailing and accommodation of through traffic in high streets • Conflicted with the preservation of character and built form of local areas • Switch in philosophy from car accommodation to car containment • Congestion charging • Speed limits • Parking restrictions • One-way systems • Local improvements • Public transport improvements • Low emission zoning • Pedestrianisation • Cycle ways • Planning restrictions and land use • Competition from out of town centres e.g. located on or near orbitals • More recently competition from internet retailing and increasing home delivery of goods and services

30. Conclusions • Urban spatial theory has stalled, not much progress as far as one can tell • However, visionary proposals are becoming more commonplace and are in fashion again • Theories are needed to validate these visionary ideas and to inform new proposals and data collections • Working with different geometries has much to offer and further to go • Important that theory does not run too far ahead of practice and vice-versa • Use of geometry as a precursor and to explore options can save money and speed up planning and evaluation

31. References • Hyman, G. and L. Mayhew.(2008) Toll optimisation on river crossings serving large cities. Transportation Research A. 42(1) 28-47 • Hyman, G. and L. Mayhew.(2004) Advances In Travel Geometry and Urban Modelling. GeoJournal 59, 191-207. • Hyman, G. and L. Mayhew.(2001) Market area analysis under orbital-radial routing with applications to the study of airport location. Computers, Environment and Urban Systems, Vol 25,195-222 • Hyman, G. and L. Mayhew (2001) Reassessing Urban Space Using Fast Route Geometry. In Transport Planning, Logistics and Spatial Mismatch, 5-21. Pion, London. • Hyman, G. and L. Mayhew (2002) Optimising The Benefits Of Urban Road User Pricing. Transport Policy Vol 9, 189-207. • Mayhew, L. (2000) Using Geometry To Evaluate Strategic Road Proposals In Orbital-Radial Cities. Urban Studies Vol 37, 13, 2515-2532. • Hyman, G,.and L. Mayhew (2000) The Properties of Route Catchments in Urban Areas. Environment and Planning B., Vol 27, 843-863. • Hyman, G. and L. Mayhew (2000) Fast Route Geometry in Urban Areas. Environment and Planning B., Vol 27, 265-282. • Mayhew, L. (1986) Urban Hospital Location. London Research Series in Geography.. George Allen and Unwin, London • Hyman, G. and Mayhew, L. (1983) On The Geometry Of Emergency Service Medical Provision In Cities. Environment and Planning A, Vol 15, 1669-1690. • Mayhew, L. (1986) Urban Hospital Location, George Allen and Unwin, London. • Mayhew, L. (1981) Automated Isochrones and the Location of Emergency Medical Services in Cities. Professional Geographer 33(4), 423-428.