Manual for Streets. MfS How Radical Is It? TRICS Conference November. Phil Jones, Phil Jones Associates. Stuart Reid, TRL

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1 MfS How Radical Is It? TRICS Conference November Manual for Streets Phil Jones, Stuart Reid, TRL

2 What are roads for? The word road derives from the Old English word for a journey on horseback: a wide way between places (OED) A road is, in essence, a highway with its main function being to accommodate the movement of traffic. (Draft Manual for Streets)

3 What are streets for? A street is a highway that has important functions in addition to traffic movement.

4 Street functions Place Movement Access Parking Drainage and Utilities (Paving the Way, CABE)

5 Place and Movement Framework Both are of equal importance Design choices need to respect both functions Movement Status Local N hood District City National Motorway Home Zone Kensington High Street Small Town High Street Trafalgar Square The Iron Bridge Local N hood District City National Place Status

6 Problems with the current system(s) Confusion of guidance: what is mandatory, what firm, what flexible? Over-use of national standards Working in silos Not setting common objectives Fear of litigation Innovation is difficult The gap in the middle

7 Standardised design criteria based around movement Cross roads: Cross roads are generally regarded as the most dangerous form of junction, largely because they imply cross traffic movement (Figure 90). They should therefore normally be avoided.

8 Lead to standardised streets...

9 That make poor places

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14 We can do better

15 We can do better

16 Manual for Streets Mission Statement Manual for Streets (MfS) is a guide to the design, construction, adoption and maintenance of new streets. Its aim is to assist the delivery of streets that: help to build and strengthen the communities they serve; meet the needs of all, embodying the principles of inclusive design provide effective and well-connected networks; are pleasant and attractive; are cost-effective to construct and maintain; and are acceptably safe.

17 Recommendations

18 Key Recommendations Team approach Network of streets Mode hierarchy Masterplans/scheme design Quality Audits Street functions Design speed of 20mph Stopping sight distances Frontage development Signing and street furniture Parking Cycle and Car

19 Key Recommendations Team approach Network of streets Mode hierarchy Masterplans/scheme design Quality Audits Street functions: Place and Movement Design speed of 20mph Stopping site distances Frontage development Signing and street furniture Parking Cycle and Car

20 Key Recommendations Team approach Network of streets Mode hierarchy Masterplans/scheme design Quality Audits Street functions: Place and Movement Design speed of 20mph Stopping sight distances Frontage development Signing and street furniture Parking Cycle and Car

21 Key Recommendations Team approach Network of streets Mode hierarchy Masterplans/scheme design Quality Audits Street functions: Place and Movement Design speed of 20mph Stopping sight distances Frontage development Signing and street furniture Parking Cycle and Car

22 Key Recommendations Team approach Network of streets Mode hierarchy Masterplans/scheme design Quality Audits Street functions: Place and Movement Design speed of 20mph Stopping sight distances Frontage development Signing and street furniture Parking Cycle and Car

23 Quality Audit Road Safety Audit Based on experience Design team barred from the process Subjective opinion, non-reproducible Problem/recommendation model Conjecture of accident causation No quantification of accident risk No factual basis for striking the right balance No means of assessing innovative designs Quality Audit Assesses safety alongside other criteria Relates to scheme objectives

24 MfS - Indicative Process Policies Objectives Design Quality Audit Implement Monitor

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26 Key Recommendations Team approach Network of streets Mode hierarchy Masterplans/scheme design Quality Audits Street functions: Place and Movement Design speed of 20mph Stopping sight distances Frontage development Signing and street furniture Parking Cycle and Car

27 Key Recommendations Team approach Network of streets Mode hierarchy Masterplans/scheme design Quality Audits Street functions: Place and Movement Design speed of 20mph Stopping sight distances Frontage development Signing and street furniture Parking Cycle and Car

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30 Key Recommendations Team approach Network of streets Mode hierarchy Masterplans/scheme design Quality Audits Street functions: Place and Movement Design speed of 20mph Stopping sight distances Frontage development Signing and street furniture Parking Cycle and Car

31 Observed Speed (km/h) Link Speeds and Site Type Measured Forward Visibility Type Of Site DB32 Compliant Historic Other Site Mean Site 85th Percentile Relationship between geometry, speed and casualties at 20 residential locations of different types No significant difference in speeds between the site types using the ATC data from links. There is however a clear trend of lower speeds with reduced visibility on links. The important factor is individual site geometries, rather than site characteristics

32 Speed at Junctions and Links Speed increases with road width and visibility for both links and junctions Speed (m ph) Road Width = 5 m Road Width = 6 m Road Width = 7 m Road Width = 8 m Road Width = 9 m Road Width = 10 m Speed (mph) Road Width = 5 m Road Width = 6 m Road Width = 7 m Road Width = 8 m Road Width = 9 m Road Width = 10 m Y Distance (m) Forward Visibility (m) Junction data Link data

33 Stopping Distances Current practice: driver reaction 2 seconds deceleration rate of 0.25g Result - 90m from 37mph and 70m from 31 mph TRL (Report 332) found 90 th percentile reaction time of 0.9s when drivers were confronted with a hazard in a simulator Modern cars can stop at approx 0.65g MfS recommends SSD based on reaction time of 1.5 seconds and deceleration of 0.45g consistent with Dutch and Australian standards - but allows flexibility Design Speed Kilometres per hour Miles per hour SSD (Metres) Zero gradient

34 Stopping Distances on Links Total Stopping Distance (metres) Total Stopping Distance (m) Stopping Distance If Speeds Not Altered (m) Available Distance (m) Forward Visibility (metres) The graph shows stopping distances from speeds expected on a 5m wide road. There is a clear margin of safety between available distance and stopping distance down to a visibility of around 20m. If road width is increased the margin of safety is reduced for each visibility.

35 Key Recommendations Team approach Network of streets Mode hierarchy Masterplans/scheme design Quality Audits Street functions: Place and Movement Design speed of 20mph Stopping sight distances Frontage development Signing and street furniture Parking Cycle and Car

36 Frontage Access Research Accident and Traffic Flow Data 20 sites with 30 mph speed limit and driveway accesses Traffic flows of 600 vpd to 23,000 vpd Very few recorded accidents involving driveways Good evidence to suggest frontage development on roads of at least 10,000 vpd (1,000 ph)

37 Key Recommendations Team approach Network of streets Mode hierarchy Masterplans/scheme design Quality Audits Street functions: Place and Movement Design speed of 20mph Stopping sight distances Signing and street furniture Parking Cycle and Car

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39 Key Recommendations Team approach Network of streets Mode hierarchy Masterplans/scheme design Quality Audits Street functions: Place and Movement Design speed of 20mph Stopping sight distances Frontage development Signing and street furniture Parking Cycle and Car

40 Progress and Programme Commenced June 2005 Project Website Literature Review/Interim Report Case Studies Completed Research Completed Consultation Draft Summer 2006 Revisions to Draft MfS underway Freeze content December 2006 Publish Spring 2007

41 How Radical Is MfS? Work from objectives not standards: apply professional skills Team approach Street functions, place alongside movement Permeable streets, maximise connections Mode hierarchy, promotion of pedestrians/cyclists Include RSA in broader Quality Audit Design speed default of 20mph for residential areas Adopt revised SSDs

42 Phil Jones: Stuart Reid: