IAN 159/12 - Standards for Highways
Contents
1. Length of Speed Length of Day Traffic Management Renewal Item 10km Period Traffic Management Requirement Roadworks Limit Speed Limit Night Duration Section years Overnight closures Gantry 13 30 see notes below Link N A N A Night 2 Nights Two lanes closed followed by switch AMI 52 12 5 to other two lanes to allow access to 1 8 km 50mph 3 4km Night 4 Nights three successive gantries Hard shoulder plus lane 1 VMS MS4 7 15 closure to allow aedass 200m 50mph 1 8km Night ANights Two lanes closed to allow HADECS cameras 2 7 5 access to one gantry 400m 50mph 2km Night 2 Nights Hard shoulder closure to HSM cameras 67 10 allow Access to cariera 500m N A N A Night N A ERA cameras 11 10 Hard shoulder closure to Renewed with N A NYA Night N A allow access to camera HSM cameras Notes Table E5 1 MIDAS amp ERA Loops do not have specific renewal periods as they afe constantly being renewing via general maintenance activities 2 Gantries are the most complex items to renew and would require a complete overnight closure of both carriageways to remove the old gantry and another closure to install the new gantry The sequence of events would involve i Removal of the electronics from the existing structure overnight with two lanes closed a any one time and a switch in the middle of the night This would have to be done twice once for each carriageway for a double span gantry ii Re2. Appendix A The Methodology for an Initial Assessment 1 IAN 159 12 The initial assessment should be based upon splitting a year into a number of flow groups One basis for this is that used within COBA which uses eight flow groups to cover four annual average weekday time periods and four annual average weekend time periods although this is not sufficient resolution for the assessment of MM HSR and it is suggested that whatever flow groups are used they should cover a maximum of 250 daytime hours IFRIIT uses 15 flow groups to describe the year with the first 12flow groups each covering 250 hours with the first flow group covering the busiest 250 hours of the year the second flow group covering the next busiest 250 hours and so forth The last three flow groups cover 1 000 1 000 and 3 760 hours respectively and itis assumed that these will relate to the offpeak hours IFRIIT requires the user to input observed flow data forthe relevantlink for every hour in a single year i e 8 760 hours in descending order of magnitude T he observed data should be available from HATRISNIhese flows are used to derive the relationships between standard AM IP and PM periods andsthe 15 flow groups representing annual flow If a full year s data are not available the tool will factor the inputs accordingly assuming _the distribution of flows nput is representative of the whole year If the distribution of flows is not_representative of the who
3. 120 110 100 Speed kph o Oo 80 70 60 Journey time information should be derived from speed flow curves developed from data from the M42 MM HSR pilot Figure D1 shows the spee d flow relationships which are included within IFRIIT and should be used in any alternate assessment method MM HSR APPRAISAL PROPOSED SPEED FLOW CURVES VE lt D3M based on COBA T ee ee 4 D4M based on COBA Se Se a 4000 1078 D3M with 50mph HSR T 3000 107 8 x sx S D3M with 60mph HSR s ae S x TR eee pi 4500 95 6 5 5 a Nes zs wy 7608 85 2 e 5706 85 2 x G a 4500 81 i ae 7608 78 2 1 0 1000 2000 3000 4000 5000 6000 7000 8000 Carriageway flow vph Figure D1 Merge Delay 3 The calculation of merge delays should use the formula described in the Design Manual for Roads and Bridges Volume 13 Section 1 Part 6 Junctions in COBA which states Research into merge delays showed that the measurement of actual average delays from on site ebservations was_ exceedingly difficult Day to day variations in delay were apparent under apparently similar flow conditions Delays varied considerably with time even within a single peak period The research was unable to differentiate between delays to the main line and merging streams Consequently COBA includes a relationship which applies delays over and above speed
4. Assessment Apply Depression Factors to post VDM DM Matrices and Reassign 4 Skim All Forecast Year Models for Input Into economic assessment Skim DM HSR Off Data amp Calculate Proportion of Average Day Economic ASSESS A Environmental Assessment Aug 2012 Interim Advice Note 159 12 Guidance Note for Traffic Consultants on the Economic Assessment of MM HSR Schemes Appendix H IAN 159 12 Amendments required to this IAN when used in projects carried out under English DBFO schemes When used on the M25 DBFO Scheme this IAN is to be amended as follows Paragraph 1 Para No Description General M25 DBFO Paragraph 18 Interpretation of Standards List applies Appendix F After Andrew Page Dove highways gsi gov uk or the IBI Group dkamnitzer ibigroup com and insert and copied to the Department s Nominee When used on all other English DBFO Schemes this IAN isto be amended as follows Paragraph 1 IAN 159 12 Para No Description 1 2 Delete the heading and paragraph and insert Not used Appendix F After Andrew Page Dove highways gsi gov uk or the IBI Group dkamnitzer ibigroup com and insert and copied to the Department s Nominee Page 31 of 31 Aug 2012
5. capital costs of traffic related maintenance should be entered as Construction costs This categorisation will ensure that the costs are accounted for in the correct categories whilst also highlighting that the additional operating costs of Managed Motorways have been accounted for The Managed Motorways Operational Cost Model includes an estimate of Present Value Costs for each of the tranche 1 Managed Motorways schemes expressed in 2002 prices Should costs be required for a new Managed Motorways scheme not presently included in the Managed Motorways Operational Cost Model the Managed Motorways Operations Programme Office should be contacted Page 26 of 31 Aug 2012 Interim Advice Note 159 12 Guidance Note for Traffic Consultants on the Economic Assessment of MM HSR Schemes Appendix G The Methodology for a Full Assessment 1 A full assessment should be undertaken for any scheme that has advanced beyond PCF Stage 0 In line with current Department for Transport guidance a full assessment must be carried out using a fully validated WebTAG compliant traffic model with variable demand capability Allowance must be made for the dynamic characteristics of the scheme either using the MM HSR IFRIIT tool in full assessment mode or equivalent methodology The requirements for modelling a dynamic intervention on the road network are complex and some generalhasSsumptions are required to be made The standard DfT TUBA program for de
6. HSR and VMSL equipment excluding gantries at 15 year intervals with gantries projected to be replaced at 30 year intervals Reporting 2 2 11 The report onthe initial assessment must include the results of the above assessments providing a comparison of the costs and benefits of MM HSR and full widening if applicable as per the pro forma in Appendix B The report will also include graphical representations of the benefit stream over time associated with full widening and MM HSR IAN 159 12 Page 7 of 31 Aug 2012 Interim Advice Note 159 12 Guidance Note for Traffic Consultants on the Economic Assessment of MM HSR Schemes 3 Full Assessment during PCF Stages 1 5 3 1 Guidance for Assessing Transport Economic Efficiency TEE Effects 3 1 1 For MM HSR schemes on the Highways Agency HA network proceeding beyond Project Control Framework PCF Stage 0 a full WebTAG compliant economic assessment must be undertaken 3 1 2 The full assessment must be based on a validated WebTAG compliant traffic model with variable demand functionality where appropriate Allowance must be made for the dynamic nature of hard shoulder running IFRIIT offers one possible way of accommodating the dynamic nature when run in full assessment mode although it is possible to modify the standard appraisal using other methods to take the dynamic mechanisms into account 3 1 3 IFRIIT calculates annualisation factors based on observed base year annual _flow profiles comb
7. MM HSR leads to a 15 reduction in personal injury accident PIA rates compared to the Do Minimum The reduction is associated with the deployment of variable mandatory speed limits VMSL and not with the utilisation of the hard shoulder as a runninglane which is assumed to have a neutral impact This is based on the reductions achieved from VMSL on the M25 and is an all day rate irrespective of the proportion of the day in which MM HSR is projected to be active IAN 159 12 Page 9 of 31 Aug 2012 Interim Advice Note 159 12 Guidance Note for Traffic Consultants on the Economic Assessment of MM HSR Schemes 3 2 2 If MIDAS has not been installed in the Do Minimum then a further 13 reduction in PIA rates can be included for MM HSR i e the accident rate should be reduced by a total of 26 1 0 85 0 87 The full assessment should be based on a full analysis of the modelled network based on WebTAG principles as is required for all major schemes 3 2 3 If VMSL and MIDAS are already in place then the safety assessment should be on the basis of the same accident rate for both the Do Minimum and Do Something Journey Time Reliability 3 2 4 An assessment of the effect of MM HSR on journey time reliability using INCA oran alternate WebTAG compliant process must be carried out for a full assessment The results of this should be reported in the Economic Assessment Report andthe Appraisal Summary Table AST although in line with current guidance
8. analyses directly Page 15 of 31 Aug 2012 Interim Advice Note 159 12 Guidance Note for Traffic Consultants on the Economic Assessment of MM HSR Schemes Appendix B Consecutive Link Assessment Methodology 1 Each link under consideration must be appraised 2 The 60 year total benefits for each link must be extracted for inclusion in the following pro forma 3 The 60 year queuing benefits for each link must be extracted for inclusion in the pro forma The queuing benefits must be deducted from the total benefits The maximum individual link 60 year queuing from all the links must be selected for inclusion in the pro forma 6 The pro forma can then be used to calculate the MM HSR benefits over consecutive links Consecutive Link Pro Forma Consecutive Link Benefit Table Total Link 1 Full 60 year benefit a Link 1 60 year queuing benefit b Link 1 Net benefit excluding queuing benefit c a gt b Link 2 Full 60 year benefit d Link 2 60 year queuing benefit e Link 2 Net benefit excluding queuing benefit f d e Link 3 Sum of net benefits excluding queuing benefits g c f Maximum recorded queuing benefit th maximum_of b or e or Consecutive link benefit i g h Table B1 Consecutive Link Benefits IAN 159 12 Page 16 of 31 Aug 2012 Interim Advice Note 159 12 Guidance Note for Traffic Consultants on the Economic Assessme
9. average Do Minimum flow for each modelled time period This depression factor will represent a reduction to the number of trips in the matrix and is applied to the post VDM Do Minimum matrices to represent the quieter portions of the year Again itis possible to calculate the uplift factor using alternate tools and the methodology of the calculation is outlined in Appendix G These matrices are then assigned foreach forecast year and the resultant flow forecasts are applicable to both the Do Minimum and Do Something environmental assessment 3 1 12 The average ofthe on and off_portions ofthe year weighted by the portion of the year in which HSR is predictedto becrequired by the annualisation factors would be the annual average so this methodology does not change the totalhannual flow and merely allows greater resolution for economic and environmental assessment purposes For some time periods in which the annualisation factors predict the use of MM HSR for the vast majority of the year perhaps 90 a case may be made that this methodology may not be required Care must also be taken that excessive noise is not caused within the model by the application of this methodology 3 2 Guidance for Assessing Other Effects Accidents 3 2 T An assessment of the effect of MM HSR on safety is mandatory for a full assessment stage gt Until long term data on the effect of MM HSR on accident rates are available it should be assumed that the introduction of
10. economic assessment is included in Appendix F 3 2 10 The works costs associated with maintenance need to include for the replacement of all MM HSR and VMSL equipment excluding gantries at 15 year intervals with gantries projected to be replaced at 30 year intervals Reporting 3 2 11 A full suite of Business Case and Funding products must be produced during PCF Stages 1 5 as laid out in the PCF product descriptions and must include a description of the application of IFRIIT The Forecasting Report must include details of the flows for both the portions of the year when MM HSR is predicted to be on and when it is predicted to be off It should also include the uplift and depression factors for each time period The Economic Assessment Report EAR must include all of the above assessments and detail the costs and benefits of MM HSR as per the standard Appraisal Summary Table AST supporting IAN 159 12 Page 10 of 31 Aug 2012 Interim Advice Note 159 12 Guidance Note for Traffic Consultants on the Economic Assessment of MM HSR Schemes worksheets namely the Transport Economic Efficiency TEE Public Accounts PA and Analysis of Monetised Costs and Benefits AMCB tables It must also include details of the annualisation factors used to calculate future year use of MM HSR IAN 159 12 Page 11 of 31 Aug 2012 Interim Advice Note 159 12 Guidance Note for Traffic Consultants on the Economic Assessment of MM HSR Schemes 4 Underlying MM H
11. flow effects to all vehicles passing through the merge area This is a simple straight line function of the form Delay 227 Capacity Ratio 0 75 seconds per vehicle 4 where the capacity ratio is defined as the total upstream demand divided by the capacity of the downstream link Figure D2 shows the development of merge delay relative to the capacity ratio IAN 159 12 Page 18 of 31 Aug 2012 Interim Advice Note 159 12 Guidance Note for Traffic Consultants on the Economic Assessment of MM HSR Schemes Queuing Delay 5 The formula used in the tool for queuing delay is based on standard queuing theory assuming queuing commences once capacity has been exceeded Delay duration is based on the time period being modelled which in the case of IFRIIT is set to one hour As the link arrival time is not known the rule of half is applied to give the average delay per queued vehicle This again is a simple straight line function Delay T 2 x V C 1 Where T is modelled period V is traffic volume and C is carriageway capacity 6 Figure D2 also shows the development of queue delay relativeto the capacity ratio Merge and Queuing Delay 600 Merge Delay Queuing Delay A 500 400 7 a amp 300 amp a 200 g 100 i gt ae i SX 0 r 0 0 2 0 4 0 6 0 8 1 1 2 1 4 Capacity Ratio V C Figure D2 7 For the purposes of an_initiahassessment merge an
12. on Opening Year Do Minimum Examine Proposed HSR Sections to Determine Status 4 Create Opening Year Network y Run Variable Demand on Opening Year Do Something re There Any Ne HSR on Sections Yes Identify Next Forecast Year a a Produce Fixed for Forecast Year Forecast Matrices __ Forecast Years are initially identified in the normal manner E Run Variable Demand on Forecast Year Do Minimum Adjust Forecast Year Marginally Backwards v Examine Proposed HSR Sections to Determine Status Was New Sectiol Activated Before This Year ave Any HSR Sections Gone Over Capacity Create Do Something Network DN Run Variable Demand on Forecast Year Do Something Yes Forecast years mist be chos n to reflect Changes A network status eitherin terms OMESR sections keing activated forthe first tim or sections reaching capacity These cofhditions will alter the gradfent of the benefit profile from that year onward Page 30 of 31 is Current Forecast Year Final Year Calculate and Depression factors Uplift Apply Uplift Factors to post VDM DM and DS Matrices Reassign DS HSR On and Corresponding DM Matrices v Skim Data for Environmental
13. the HA TAME group TEE and Accident Impacts due to Maintenance and Construction 2 2 6 An assessment of the effects of changes in delay due to the maintenance and construction of MM HSR using the scheme model QUADRO or alternative similar assessment may be carried out for the initial assessment stage if the required information is available 2 2 7 An outline of the additional maintenance required for an MM HSR scheme and the likely traffic management regime is included in Appendix E 2 2 8 During periods of maintenance the hard shoulder gives scope for areas of the normal running carriageway to be removed without loss of capacity Once MM HSR has been implemented this flexibility is not available during periods ofshigh traffic flows which in addition to the possibly higher traffic flows under MM HSR may lead to an increase in delays during periods of maintenance Costs 2 2 9 Increased operational costs associated with MM HSR should be included in the scheme costs for the initialhassessment including any additional staffing costs resulting from additional monitoring by Regional Traffic Control Centre RTCC staff and an increased number of patrols by traffic officerssDetails of these costs can be obtained from the Managed Motorways Delivery Office Guidance on incorporating these costs in the economic assessment is included in Appendix Fz 2 2 10 The works costs associated with maintenance need to include for the replacement of all MM
14. traffic modelling 3 1 6 IFRIIT_also offers the ability to easilyidentify the control link for each time period for each forecast year ise theJink that controls whether or not the scheme would be switched on during a given time period and thus controls the annualisation factor although this could be determined from the traffic model The control link may change between periods and between forecast years 3 1 7 Aneconomic_assessment based on the annual average flows in a modelled period will lead to an understatement of the benefits of MM HSR As an extreme example if the annual average flow forthe period is less than the switch on threshold for using the hard shoulder then there would be no benefits predicted at all even though parts of the year would exceed the threshold It is therefore necessary to calculate for each modelled time period the annual average flow of when the hard shoulder is switched on and the annual average flow of when it is switched off 3 1 8 To ensure that the flows on the rest of the network in the model are proportionate to the annual average flows when the hard shoulder is and is not in used adjustment factors uplift for when the hard shoulder is in use and depression when it is not need to be applied to the overall trip matrix IAN 159 12 Page 8 of 31 Aug 2012 Interim Advice Note 159 12 Guidance Note for Traffic Consultants on the Economic Assessment of MM HSR Schemes 3 1 9 To facilitate this IFRIIT calc
15. Equipment Renewal Schedule 9 In addition to regular maintenance activities it will als b necessary for equipment to be renewed atcertain intervals Table E5 overleaf provides a schedule of equipment renewal periods and associated traffic management requirements for one carriageway of a typical 10km_ section of managed motorway Major Maintenance 10 Major maintenance activities requiring prolonged periods of temporary traffic management will need to be assessed using either QUADRO or the scheme traffic model The traffic flows Should be based upon those forecast by the model for the year in which the maintenance to take place or if necessary interpolated between available forecast years Use of the hard shoulder as a running lane during periods of high demand may resultin predicted traffic volumes higher than in the Do Minimum If the analysis indicates that this higher demand will lead to excessive user delays during periods of maintenance when the hard shoulder is unavailable then discussions should take place with the scheme team about further options for the projected maintenance such as minimum capacity during peak periods or restricting lane closures to offpeak periods 1 Repairs and cleaning carried out at the same time IAN 159 12 Page 23 of 31 Aug 2012 Interim Advice Note 159 12 Guidance Note for Traffic Consultants on the Economic Assessment of MM HSR Schemes Qty per Renewal
16. Interim Advice Note 159 12 Guidance Note for Traffic Consultants on the Economic Assessment of MM HSR Schemes INTERIM ADVICE NOTE 1597 12 Guidance Note for Traffic Consultants on the Economic Assessment of MM HSR Schemes Summary The objective of this document is to assist in the economic assessment of MM HSR schemes and to assist use of the Initial and Full Responsive Intervention Investment Tool LFRIIT by detailing key guidance and information relevant to its use Instructions for Use This IAN provides guidance and information for immediate use IAN 159 12 Page 1 of 31 Aug 2012 Interim Advice Note 159 12 Guidance Note for Traffic Consultants on the Economic Assessment of MM HSR Schemes Contents 1 Introduction 4 1 1 Background 4 1 2 Documents 4 Department for Transport Published Documents 4 Highways Agency Published Documents 4 1 3 Project Control Framework PCF 5 1 4 Required Components of Economic Assessment by PCF Stage 6 2 Initial Assessment during PCF Stage 0 7 2 1 Guidance for Assessing Transport Economic Efficiency TEE Effects 7 2 2 Guidance for Assessing Other Effects Z Accidents 7 Journey Time Reliability 8 TEE and Accident Effects due to Maintenance and Construction 8 Costs 8 Reporting 8 3 Full Assessments during PCF Stages 1 5 9 3 1 Guidance for Assessing Transport Economic Efficiency TEE Effects 9 3 2 Guidance for Assessing Other Effects 10 Accidents 10 Journey Time Reliability 11 TEE and Accident Effe
17. SR Assumptions 4 1 1 All appraisals of MM HSR should be based on the assumption that hard shoulder running is equivalent to the provision of a full extra lane i e the hard shoulder has the same operating capacity as a conventional lane this assumption should be retained through any assessment 4 1 2 The results of the M42 MM HSR pilot have been used to develop an MM HSR speed flow curve and to determine the flow at which MM HSR should be activated This flow has been determined to be 1 500 vehicles per lane per hour 4 500 vehicles across a three lane carriageway This is equivalent to a speed of around 60mph This assumption was developed from the application of MM HSR at 50 mph but the same activation flowis to be assumed for MM HSR operating at 60mph The speed flow curve is available from TAME on request and should be used to represent traffic behaviour under MM HSR in any assessment IAN 159 12 Page 12 of 31 Aug 2012 Interim Advice Note 159 12 Guidance Note for Traffic Consultants on the Economic Assessment of MM HSR Schemes 5 Contacts 5 1 1 Queries on this document should be made to IAN 159 12 Roger Himlin Traffic Appraisal Modelling and Economics Room 406 City Tower Piccadilly Plaza Manchester M1 4BE Tel 0161 9305672 GTN 4315 5672 Email roger himlin highways qsi gov uk Page 13 of 31 Aug 2012 Interim Advice Note 159 12 Guidance Note for Traffic Consultants on the Economic Assessment of MM HSR Schemes
18. Transport publishsmany documents that outline the various aspects of transport assessment although none dealdirectly with the subject of MM DHS These documents do however provide all the informationequired on economic assessment e Design Manual for Roads and Bridges DMRB Volume 12 Traffic Appraisal of Road Schemes COBA DMRB Volume 13sEconomic Assessment of Road Schemes QUADRO DMRB Volume 14 Economic Assessment of Road Maintenance INCA Incident Cost_Benefit Assessment User Manual TUBA Transport User Benefit Appraisal Manual WebTAG Transport Analysis Guidance Highways Agency Published Documents 1 23 The use of MM HSR is a complex and developing process Additional documents that may assist inthe understanding of MM HSR implementation and possible future developments are e IAN 111 Managed Motorway Implementation Guide Dynamic Use of the Hard Shoulder e IAN 112 Managed Motorway Implementation Guide Through Junction Hard Shoulder Running IAN 159 12 Page 3 of 31 Aug 2012 Interim Advice Note 159 12 Guidance Note for Traffic Consultants on the Economic Assessment of MM HSR Schemes 1 3 Project Control Framework PCF 1 3 1 All Major Projects road improvement schemes with a value of over 10m are subject to the planning stages presented in the Project Control Framework The PCF is defined by a simple matrix consisting of a total of 8 PCF Stages Pre Project Stage 0 Strategy Shaping amp Prior
19. at MM HSR will lead to a 15 reduction in personal injury accident PIA rates compared to the Do Minimum The reduction is associated with the deployment of variable mandatory speed limits VMSL and not with the utilisation of the hard shoulder as a running lane which is assumed to have a neutral impact This is based on the reductions achieved from VMSL on the M25 and is an all day rate irrespective of the proportion of the day in which MM HSR is projected to be active IAN 159 12 Page 6 of 31 Aug 2012 Interim Advice Note 159 12 Guidance Note for Traffic Consultants on the Economic Assessment of MM HSR Schemes 2 2 2 If Motorway Incident Detection and Automatic Signalling MIDAS has not been installed in the Do Minimum then a further 13 reduction in PIAs can be included i e the accident rate should be reduced by a total of 26 1 0 85 0 87 The initial assessment should be link based using the above factors to derive the scheme safety benefits 2 2 3 If VMSL and MIDAS are already in place then the safety assessment should be on the basis of the same accident rate for both the Do Minimum and Do Something Journey Time Reliability 2 2 4 An assessment of the effect of MM HSR on journey time reliabilitymay be carried out during the initial assessment stage if the required information is available 2 2 5 Details of what assumptions should be made in the assessment of the impact_of MM HSR on journey time reliability are available from
20. cts due to Maint nance and Construction 11 Costs 11 Reporting 11 4 MM HSR Assumptions 12 5 Contacts 12 Appendices 13 IAN 159 12 Page 2 of 31 Aug 2012 Interim Advice Note 159 12 Guidance Note for Traffic Consultants on the Economic Assessment of MM HSR Schemes 1 Introduction 1 1 Background 1 1 1 This document is intended as a guide for consultants undertaking an economic assessment of schemes involving Managed Motorways Hard Shoulder Running MM HSR and introduces the Initial and Full Responsive Intervention Investment Tool IFRIIT The tool operates in two modes depending on the stage of assessment i Initial assessment mode used for strategy shaping and prioritisation tovassess whether MM HSR is a viable option for a particular location on a tink by link basis or ii Full assessment mode used in later stages of the Project Control Framework RGF to appraise schemes in greater detail 1 1 2 The objective of this document is to assistin the economic assessment of MM HSR schemes and the use of the MM HSR Initial and Full Responsive Intervention Investment Tool It details key guidelines that the economic assessment and_use of the toolmust adhere to whilst highlighting assumptions that can be made 1 2 Documents 1 2 1 The Department for Transport and Highways_Agency documents which are relevant to the following guidance in this document are as follows Department for Transport Published Documents 1 2 2 The Department for
21. d queuing delay should be combined to provide a single delay figure Thesmerge delay should be used up to a point where the delay predicted by the assessment of queuing delay exceeds the predicted merge_delay Figure D3 illustrates the methodology that should be used Merge and Queuing and Applied Delay 600 SEERE Merge Delay Queuing Delay 500 Applied Delay Delay s wo O Q De is fo 100 0 0 2 0 4 0 6 0 8 1 1 2 1 4 Capacity Ratio V C Figure D3 IAN 159 12 Page 19 of 31 Aug 2012 Appendix E Interim Advice Note 159 12 Guidance Note for Traffic Consultants on the Economic Assessment of MM HSR Schemes Maintenance and Associated Traffic Management Requirements of MM HSR Introduction 1 This appendix describes typical maintenance and associated traffic management activities that would be required on Managed Motorways insofar as they impact on driver delays The information can be used as the basis for including driver delays associated with repairs on Managed Motorways into an economic assessment Traffic is Location of Management Item Description liam Density Required for Access Lightweight access Gantry ire e requires cherry Over Every 850 metres Yes picker to access carriageway equipment Lane signal to display One perlane sda i speed limit and lane including hard essage Indicators I divert On gantry ho ld h Ye
22. e default assumptions of 3 hour AM and PM periods and a 6 hour IP period this gives maximum annualisation factors of 783 for the AM and PM periods and 1 566 for theP The offpeak period is assumed to cover the 12 night time hours of all 865 days leading to a maximum annualisation factor of 4 380 whilst the weekend period is assumed to coverthe 12 daytime hours of Saturday and the 12 daytime hours of Sunday leading to amaximum factor of 1 248 These total to cover the full 8 760 hours of a year Traffic flow data from the annual average based traffic model for each time period for the base year and all forecast yearssshould be usedto calculate future year annual flow profiles At this pointa prediction can be made about the hours within each period during which HSR is likely to be required and the relationship between the average flow during these hours andthe annual average of the period can be calculated to provide an uplift factor Equally the relationship between the average flow in hours when HSR is notvequired_and the annual average period flow will provide a depression factor IFRI calculates these factors for each time period and each year The application of thesefactors to the model forms the basis of the split to accommodate the dynamicnature of HSR If for some reason an economic assessment needs to be undertaken and the results of a traffic model are_notvavailable the average flow for each period for the base year could be man
23. g Annual ciganing Night time lanes to llow access to six successive gantries ek S0mph Sent Soller z EE EA Two lanes closed L2 amp 3 leaving traffic running on lane If hard fag gets so aver ri will have shoulder running is possible thenalso close lane 1 to give alarger MIDAS loops Se failures A ear Night time Jwork area After having cut and installed the loops in lanes 2 and 3 400m 50mph 2km Re anin 6 E ea log th MMarrangementwould change s th t traffic would run in lanes q P Op 2 amp 3 and close the HS orlane i and the HS as appropriate when at least two loops fail HADECS Annual inspection and cleaning Night time Two lanes closed to allow access to one gantry 400m 50mph 2km Daytime Hard shoulder closure assuming ground HSM cameras Cleaning twice per year inter peak accessible wash Wwipe mechanism 2 5km N A N A Repairs with frequency Ne Ne Hard shoulder closure to allow access to HSM cameras based on a 10 failure rate Nighttime camera including alignment 900m VA NA Repairs with frequency ve ERA loops based on A15 Bail ReNcatd Night time Hard shoulder closure to allow access to ERA plus working space 400m N A N A ERA cameras Cleaning twice per year Daytime None done as part of HSM camera cleaning closures N A N A N A Repairs with frequency vee ERA cameras based on a 10 failure hats Night time_ tH rd shoulderclosure to allow access to ERA plus working space 400m N A N A Table E2 Required Maintenance and Traff
24. hat the network surrounding a scheme includes a section on which MM HSR is already present and this section will also have a controlling link Since this link would be present in both the Do Minimum and Do Something its impact is neutral on the scheme assessment and it is only the new controlling link that is pertinent It can reasonably be assumed that the neighbouring scheme will be active when the assessed scheme is active and inactive when the assessed scheme is inactive IAN 159 12 Page 29 of 31 Aug 2012 Interim Advice Note 159 12 Guidance Note for Traffic Consultants on the Economic Assessment of MM HSR Schemes MM HSR Full Assessment Methodology Page 1 Modelling Phase IAN 159 12 This procedure is operationally constrained dividing a proposed HSR route into sections that will be turned on together for safety and operational reasons and should be informed by the Initial assessment results This should be identified from the Initial assessment i e Whether each operationally constrained section is activated or not This will be done by changing identified HSR on sections to have an additional lane and the HSR speed flow curve Identify HSR Sections Identify HSR Opening Year _ Do Something ae Modelling Model Base Year as standard Produce Fixed Opening Year Forecast Matrices Run Variable Demand
25. he application of the upliftfactor may result in a significant increase in congestion and therefore model noise within the area Care should be taken to increase model convergence as much as is practicable in order to minimise such effects Data should be passed tothe teams undertaking the environmental assessments primarily the air quality and noise assessments alongside an indication of the daily average time that each situati n represents For example a fullassessmentsnas indicated that for a proposed scheme HSR would be turned on for 1 050 hours of the six hour IP period over the course of the opening year The average IP flow whilst HSR is on is 5 000 vehicles and 3 500 when it is off These flows should inform the environmental assessment with the note that the HSR on flow represents 4 hours of an average weekday in the opening year 6 x 1 050 261 x 6 where the 1 050 refers to the numberof hours that HSR is on 261 is the number of weekdays in_ayearand 6 is the number of hours in the modelled period whilst the HSR off flow represents the remaining 2 hours of the IP in the average weekday This finer resolution can then be used in the AQ emission and noise assessments On occasion a scheme_may consist of two separate sections each with a controlling link This would lead to complex operational patterns and guidance should be sought from the Highways Agency TAME group early in the modelling process Another possibilityis t
26. ic Management IAN 159 12 Page 22 of 31 Aug 2012 Interim Advice Note 159 12 Guidance Note for Traffic Consultants on the Economic Assessment of MM HSR Schemes Qty per Cleaning mallitenanee 10km Inspections Day Frequency Traffic Management Requirement Item Night Section per Year HS and lane 1 closed with 50mph pally i 1 pay e Per yea limit for 3 6km four times per year HS and lane 1 closed with 50mph 13 limit for 5 8km twice per year AMES VMS Gantries 1 Night 12 par year Lanes 2 and 3 closed with 50mph limit for 5 8km twice per year HADECS One lane closed with 50mph limit cameras 1 Mant 2 per year for 2km twice per year HSM HS closed with no reduced speed cameras oi Day BPeky ee limit for 25km eighttimes per year ERA 11 2 Day Included in HSM cameras cameras Table E3 Sample Cleaning Inspection Schedule for 10km Section of MM HSR Qty per Repairs Traffic Management_ Day Meinienance ltem 10km Section Ate Year Frequency S Night AMI Over lane 1 HS 13 2 2 per year Night AMI Over lanes 2 3 4 139 2 Q peryear Night VMS MS4 7 lt 1 t per2 years Night MIDAS Loop pairs 25 26 26 per year Night HADECS cameras 2 o per year Night HSM cameras 67 7 7 per year Night ERA detector loops 11 3 4 4 per year Night ERA cameras 11 1 Tper year Night Table E4 Sample Repair Schedule for 10km Section of MM HSR Typical
27. ined with flows from models created for annual average weekday AM interpeak and PM periods and where available off peak and weekend periods These annualisation factors can be used with a special version of TUBA available fromthe supplier or an alternate WebTAG compliant process which allow for varying annualisation profiles in future forecast years The annualisation factors representing the proportion of the year that MM HSR is active should be assumed to change in a linear fashion between modelled years The methodology to be employed in a full assessment is givenin Appendix G 3 1 4 The full assessment needs to include all the elements of economic appraisal for a major scheme including the effects on accidents maintenance and journey time reliability The assessment must be undertaken over the standard 60 year appraisal period and it must be remembered that the technological equipment associated with MM HSR e g CCTV cameras and variable mandatory speed limit VMSL signs willneed to be replaced every 15 years whilst the supporting gantries will need to be replaced on every 30 years 3 1 5 The full assessment should reflect the operational requirements of MM HSR including the number of links that would be activated_togetherto form contiguous sections and the hours over which the section would be operational The gt results of the initial assessment will help to inform these operational requirements which will need to be included in the
28. ities would be undertaken during peak periods Day time activity would be restricted to the interpeak period preferably during_portions of the year when HSR is not required and night time activity to times when flows are lowest e g 22 00 and 06 00 A simple assumption would be that the traffic management indicated in the table would be in place for the duration of these periods 5 The only exception to these restricted access times would be Category 1 defects which may require traffic management fromthe time at which the defect is identified until the time it has been made safe At this time there is no evidence that Managed Motorway sections would be any more prone to Category 1 defects that any comparable section of non gt dynamic motorway Speed Limit within Roadworks 6 There is a system restrictionthat prevents a red X being placed on the hard shoulder without setting speed limits_on the rest of the gantry However it is possible to close the hard shoulder for maintenance without using the signals i e using cones and signs n such circumstances a 50mph restriction is not required 7 Where runningJane 1 is closed it is usual but not always required to introduce a 50mph limit Where twolanesyare closed however a 50mph limit is always introduced Table E2 assumes that a 50mph limit is always applied Typical Maintenance Schedule 8 Tables E3 and E4 provide sample schedules of cleaning inspection and equipment maintena
29. itisation Stage 1 Option Identification Options Stage 2 Options Selection Stage 3 Preliminary Design Development Stage 4 Statutory Procedures amp Powers Stage 5 Construction Preparation Stage 6 Construction Commissioning_ amp Handover Construction Stage 7 Closeout 1 3 2 For Managed Motorways schemes Stages t and 2_may be combined where there is to be no formal public consultation and it is possible for Stages 3 4 and 5 to be combined where there is no IPC Statutory Process requirement under Stage 4 1 3 3 The MM HSR Initial and Full Responsive Intervention Investment Tool IFRIIT should be used to inform economic assessment during Stage 0 and to aid in the production and refinement of the Economic Assessment Report EAR throughout Stages 1 to 5 of the PCF process e During PCF Stage 0 IFRIIT canbe used ininitial assessment mode e During PCF Stages 1 5JFRNT should be used in full assessment mode 1 3 4 During schemes wher MM HSR is being suggested as an alternative option it may be plausible to use IFRIIT in initial assessment mode during Stage 1 this approach should be discussed with the HA TAME group before being adopted IAN 159 12 Page 4 of 31 Aug 2012 Interim Advice Note 159 12 Guidance Note for Traffic Consultants on the Economic Assessment of MM HSR Schemes 1 4 Required Components of Economic Assessment by PCF Stage 1 4 1 As a scheme progresses through the PCF greater refinemen
30. le year i e a whole month s data are missing then this data should be in filled The user should report the percentage of th base year s data available out of 8 760 hours and the methodology agreed with the TAME group used to infill data If no data is available default factors are available within IFRIIT During an initial assessment a user must also account for traffic growth in future years If using IFRIIT the user mustinput traffic growth data from the scheme traffic model if available or if ascheme model is notvavailable locally adjusted growth factors from the National Transport Model should be used An initial assessment not undertaken using IFRNT should also use growth data from these sources An initial assessment should take into account the effect of geometry on the speed of traffic in line with the guidance provided in the Design Manual for Roads and Bridges Volume 13 Section1 Part5 Speeds on Links The curves for the existing motorway should be calculated from these principles whilst the curve for MM HSR is available from the HA TAME group IFRIIT allows the user to input bendiness and hilliness in order to calculate this impact During an initiahassessment the proportion of vehicle types must be utilised in the benefit calculation tisssuggested that the proportion should be taken from observed manual counts where possible or if not available use should be made of the defaultproportions outlined in the Desig
31. m 2 The Managed Motorways Operational Cost Model contains operating cost estimates for individual schemes The bottom right hand corner of each individual scheme sheet contains the 60 year expenditure profiles of estimated operating costs that need to be incorporated intothe scheme economics 3 The cost estimates represent the additionalwmaintenance operating and_renewal costs compared to non Managed Motorway operation No costs are included that would also be incurred in the Do Minimum 4 The model presents annual costssthat incorporate assumptions_ regarding cost reductions over time for specific costitems e g efficiencies in maintenance reduced need for Managed Motorway infrastructure and_therefore renewals The Operations Programme Office is of the opinion that such_assumptions should be included when estimating the cost profile over 60 years and therefore these should be applied in the version of the costs used inthe scheme economic assessment 5 The costs presented in the model allow for predicted differences between general inflation and inflation in scheme cost items as required by WebTAG Unit 3 5 9 No further adjustment in this regardis necessary when undertaking an economic assessment 6 The Managed Motorways Operational Cost Model does not include a specific allowance for optimism bias as the estimates already include contingency and therefore additional optimism bias should not be added 7 Thecosts exclude all VAT
32. moval of the span overnight complete closure iii Removal of the existing vertical supports and installation of new supports hard shoulder closure for 24 hours on each carriageway iv Installation of the new span overnight complete closure v Installation of the new electronics overnight with 2 lanes closed at any one time and a switch in the middle of the night This would have to be done twice once for each carriageway for adouble span gantry Assuming all gantries are renewed_on a link then the overnight link closures would be used to remove and install all gantries on the link Additional traffic management before and after the closures may however be required for removal installation of electronics IAN 159 12 Page 24 of 31 Aug 2012 Interim Advice Note 159 12 Guidance Note for Traffic Consultants on the Economic Assessment of MM HSR Schemes Appendix F The Inclusion of Operating Costs in the Economic Assessment of MM HSR 1 This appendix provides advice on incorporating operating cost estimates from the Managed Motorways Operational Cost Model into the economic assessments of individual MM schemes Further explanation of the cost model is provided in the note entitled Managed Motorways Guide to the Operational Cost Model Any queries concerning the cost model should be directed to the Managed Motorways Operations Programme Office Andrew Page Dove highways gsi gov uk or the IBI Group dkamnitzer ibigroup co
33. n Manual for Roads and Bridges Volume 14 Section 1 Part 5 The Traffic Input to QUADRO IFRIIT allows either of these sources inNnitial assessment mode An initial assessment should predict the impact of the scheme in each future year over the assessment period IFRIIT interpolates traffic growth between AM IP PM periods in the modelled years to derive a flow for each period in each future year Flat i e zero traffic growth is assumed after the final modelled year From the predicted hourly flows the flows within the 15 flow groups of each year are then calculated The flows in each flow group are then capped at the capacity of the widened motorway This should not occur if growths have been derived from a Page 14 of 31 Aug 2012 IAN 159 12 Interim Advice Note 159 12 Guidance Note for Traffic Consultants on the Economic Assessment of MM HSR Schemes variable demand model A similar methodology should be undertaken if utilising a different method to undertake an initial assessment For each year and each scenario the speed flow curves should be used to calculate link transit times An assessment of merge and queuing delay should be included in the initial assessment in line with the details in Appendix D Within IFRIIT the merge delay is calculated as per DMRB Volume 13 and the queuing delay calculated using standard queuing formulae as per DMRB Volume 14 and the higher of these two used to calculate the applicable delay It is inhere
34. nce and associated traffic management requirements for one carriageway of a typical 10km section of Managed Motorway IAN 159 12 Page 21 of 31 Aug 2012 Interim Advice Note 159 12 Guidance Note for Traffic Consultants on the Economic Assessment of MM HSR Schemes ie Speed Limit Length of Item Required Maintenance ia g of Required Traffic Management Hank a within Road with Roadworks Speed Limit Hard shoulder plus lane 1 closure to allow Gantry Annual inspection Daytime access to three successive gantries 2 km 50mph 3 6km Gantry ae inspection every Daytime Hard shoulder plus Jane 1 closure to allow access to_one gantry 200m 50mph 1 8km AMI Repairs with frequency rer over hard shoulder based on a 17 failure rate Night time Hard shoulder plus lane tsclosure to allow access to one gantry 200m 50mph 1 8km AMI Repairs with frequency maa over lanes 1 amp 2 basedon a 17 failure rate Night time Three lanes closed to allow access_to three s ecessivegantries 138 km 50mph 3 4km PNI Repairs with frequency Night time Two lanes closed to allow access to three successive gantries 1 8 km 50mph 3 4km over lane 3 based on a 17 failure rate Repairs with frequency AREH MS4 based on a 10 fail re fate Night time Hard shoulder plus lane 1closure to allow access to gantry 200m 50mph 1 8km VMS amp AMI nas Two lanes closedfollowed by switch to other two Annual Cleanin
35. nt of MM HSR Schemes Appendix C Reporting Pro Forma PCF Stage 0 MM HSR D4M User Benefits Total Total Travel Time Queues Merges g Vehicle Operating Costs e Travel Time and Vehicle Operating Costs During Construction O During Maintenance e TOTAL f a b c d e Table C1 TEE table MM HSR D4M Govt Funding Total Total Operating Costs g Investment Costs h Indirect Tax Revenues i NET IMPACT PVC j g h i l Table C2 Public Accounts MM HSR D4M Impact Total Total TEE Benefits f Accident Benefits k Total PVB M fK Govt Funding Pvc i Overall Impact NPV m i BCR n Mj Table C3 Analysis of Monetised Costs and Benefits Notes 1 Both D4M and MM HSRdata to_be taken from the MM HSR IFRIIT tool or alternate appraisal 2 Calculated external to the appraisal IAN 159 12 Page 17 of 31 Aug 2012 Interim Advice Note 159 12 Guidance Note for Traffic Consultants on the Economic Assessment of MM HSR Schemes Appendix D Basis of Initial Economic Assessment 1 The calculation of the benefits generated by the scheme should be based on the impacts on journey times merge delays queuing delays and vehicle operating costs as well as the impact on indirect tax revenue Journey Time 2
36. nterim Advice Note 159 12 Guidance Note for Traffic Consultants on the Economic Assessment of MM HSR Schemes 2 Initial Assessment during PCF Stage 0 2 1 Guidance for Assessing Transport Economic Efficiency TEE Effects 2 1 1 An initial assessment is appropriate for PCF Stage 0 and should be carried out using the IFRIIT tool available from the Highways Agency Traffic Appraisal Modelling and Economics TAME group or an alternate WebTAG Web based Transport Analysis Guidance compliant process The benefits predicted from the tool are based on observed flows from the Highways Agency TRaffic Information System HATRIS with growth factors from either a scheme traffic model if available or otherwise from TEMPRO or the National Transport Model The tool calculates link transit time benefits benefits from the relief of queuing merge delays and vehicle operating cost VOC impacts It does not assess the safety impact or the economic effects of MM HSR on the wider_network beyond the motorway link being considered neither does it provide daton scheme costs Scheme costs calculated in terms of a Present Value Cost need to be derived outside the tool 2 1 2 The benefits predicted by the tool over the standard appraisal period coupled with any additional benefits as outlined in Section 1 4 can then be used in conjunction with scheme costs to ascertain whether MM HSR is an economically viable option he methodology to be employed during the initial as
37. ntly assumed that these sources of delay will either be at the merge with a slip road or the downstream end of the link The monetised journey time impacts should be a combination of the impact on link transit times and the impact on the predicted queuing merge delay multiplied by the value of time VoT calculated in line with WebTAG Unit 3 5 6 gt Values of Time and Operating Costs IFRIIT does this internally for each scenario for each year The vehicle operating cost VOC impacts in terms_of both fuel and non fuel impacts should also be calculated in line with WebTAG Unit 3 5 6 and the indirect tax revenue ITR changes calculated from the fuel element The average speeds used to assess the vehicle operating costs should take into account the impact of merge and queuing delay on the speeds predicted by the speed flow curves This is done inherently within IFRIIT The annual economic impacts should be provided in discounted and undiscounted form and 10 20 and 60 year summaries of the discounted benefits should be given The year that MM HSRiis first required afterits installation date should be compared to the opening year of full widening ifthis is also being assessed The summaries should be aggregated from the earlier year of these two years for each scenario The discounted benefit streams should also be presented in a graphical form with the first years in which MM HSR would be effective indicated IFRIIT is set up to provide these
38. portions of the year also need to be modelled In this case where the Do Something does not include any interventions that are present during the entire year this is equivalent to the Do Minimum as the MM HSR will not be in operation and therefore the depression factors should only be applied to the Do Minimum post VDM matrices and the results used for both the with and without scheme cases In some cases the Do Something may include additional non dynamic interventions such as junction improvements or adjacent carriageway widening In these cases the above assertion that the Do Something with HSR off s equivalent to the Do Minimum is false and additional modelling is required A network including the non dynamic Do Something improvements would be required and the depression factors would need to be applied to post variable demand matrices from this network This post VDM depressed matrix would then need reassignment on this network and the results used in both the economic and environmental assessments For schemes were it is identified that the annualisation factors for a given period cover the majority of the year e g 90 and therefore the calculated uplift factors are minimal the above methodology need not be applied as the impact will be negligible Advice on this should be sought from the HATAME group Care must be taken where areas of heavy congestion appear within the modelled area e g an urban area in a peak period as t
39. rim Advice Note 159 12 Guidance Note for Traffic Consultants on the Economic Assessment of MM HSR Schemes conditions flows and speeds do not correctly identify benefits for annualisation or provide accurate flows for air quality AQ and noise assessments Models must be converted from an annual average basis to a basis that provides two separate estimates of flows and speeds one representing the segments of a time period in the year in which MM HSR is active and the other to reflect traffic conditions when MM HSR is not active The full assessment mode of IFRIIT offers a simple tool to do this although it is possible to do this conversion in other ways Any such method including IFRIIT will require annual flow profile information for the model base year for each scheme link IFRIIT allows this input for each direction and has allowance for ten links Shoulda scheme be developed with more links and IFRUT used advice can be sought from the HA TAME group If the full base year s data are not available it is the responsibility of the user to in fill the gaps within the datasThe user should report the percentage of the base year s data available out of 8 760 hours sand_the methodology agreed with the TAME group used to infillhdata IFRIIT does not determine the presence of bank holidays and provides annualisation factors on the assumption that the AM IP and PM periods cover all 261 weekdays rather than the 253 working weekdays Under th
40. s AMI closure dive shoulder on eac messages gantry MS4 Variable kakoe Da On gantry over On every one gantry Y Message Sign sign with graphics hard shoulder every 1700 metres es capability Loops i roa d One loop pair per Inductance loop cut as surface lane including hard MIDAS loops loop pair controller at shoulder every Yes roadside 400m HADECS Digital camera used One camera every 2 Highways Agency Pe earned entre of On gantry over link junction to Yes Digital Enforcement dynamic speed limits selected lane junction stretch of Camera System y P motorway Hard Shoulder Fixed CCTV camera On inverse J gt Every 150 to 200 m Monitori used tocheck that shaped pole depends on road onitoring HSM h f Yes cameras ard shoulder is Clear mountedsin the alignment and prior to opening verge location of structures Emergency Refuge Inductance loopused No maintenance Areas ERA monitor vehicle entry Ln 5 oe ae 2 vehicles park in detector loops exit from ERA 9 p3p ERA or lay bye OMg la behigd No maintenance ERA Fixed cam ra used to _ barrier E hicl ki cameras monitor the ER upstream of very 850 metres vehicles park in ERA ERA or lay bye Emergency Telephone for s No maintenance Roadside emergency use by bea pening Every 850 metres vehicles park in Telephone motorists ERA or lay bye Combined No maintenance Equipment ae a hause A verge behind Various vehicles park in Cabingic roadside electronic
41. s arrier ERA or lay bye Table E1 MM HSR Infrastructure Requiring Maintenance and Traffic Management IAN 159 12 Page 20 of 31 Aug 2012 Interim Advice Note 159 12 Guidance Note for Traffic Consultants on the Economic Assessment of MM HSR Schemes 2 Managed motorway technology equipment will usually be located in roadside cabinets in the verge near an ERA wherever possible Some equipment is mounted on columns in the verge or on overhead gantries There are also detectors buried in the carriageway including in the ERA pavement e Roadside cabinets in the verge will generally be behind a barrier In most cases the equipment would be near an ERA or maintenance lay by where maintenance vehicles will park As a result no traffic management would be required e Equipment located on gantries over running lanes and detectors in the carriageway will require traffic management e Equipment mounted on columns in the verge over the hardsshoulder on gantries and in the ERA pavement will require traffic management Required Maintenance and Traffic Management Activities 3 Table E2 overleaf describes the required maintenance and associated traffic management activities for Managed Motorways equipment Only equipment which would require traffic management in order to be maintained is included Duration of Works 4 All the activities listed are of short duration i e afew hours It can be assumed that none of these activ
42. sessment is given in Appendix A 2 1 3 The initial assessment mode of IFRI is link based withimpacts being calculated for an individual link When MM HSR is proposed over consecutivelinks the link transit merging and VOC benefits for each adjoining link on the section of the network being considered for MM HSR should be added together to provide the overall level of benefits However the queuing delays from each link cannot be simply added together as the queuing delay on one link has an effect on the adjacent link s therefore only the highest recorded queuing delay calculated from all the links assessed should be used The methodology to be used when carrying out a consecutive link assessment is givenin Appendix B 2 1 4 The pro forma that should be used to record the economic assessment results is included in Appendix C If full widening is being considered as an option IFRIIT should be used to undertake this in orderto ensure Consistency inxthe assessment between options This pro forma therefore includes the option of full widening to simplify reporting 2 1 5 Appendix D includes the assumptions and details of the calculations undertaken within the initial assessment mode of IFRIIT 2 2 Guidance for Assessing Other Effects Accidents 2 2 1 An assessment of the effectofMM HSR on safety is mandatory for the initial assessment stage gt Until long term data on the effect of MM HSR on accident rates are available it should be assumed th
43. t of the economic assessment is required The initial assessment at Stage 0 is intended to be a guide to the likely impacts of the scheme whilst later stages focus on refining the assessment As such not all components of economic assessment are required at each stage The table below highlights when any given component may be treated as optional PCF Stage Component Status Cost to include preliminary assessment of additional Required maintenance and operational costs Accident analysis Required Impact of maintenance on users Optional Impact of construction on users Optional 0 Journey time reliability Optional Alternative forecasting scenarios Optional Wider economic impacts impacton Regeneration Areas Optional Greenhouse gases carbon Optional Noise Optional Cost including full estimate of maintenance and operational cost Required Accident analysis Required Impact of maintenance on users toincludereplacement of technology every 15 years Pequirse Impact of constructiononusers Required 1 5 Journey time reliability Required Alternative forecasting scenarios Required Wider economic impacts impact on Regeneration Areas Required Greenhouse gases carbon Required Noise Required This indicates that invin with standard procedures under WebTAG an assessment is required to determine the presence of an impact If an impact is identified then it must be quantified IAN 159 12 Page 5 of 31 Aug 2012 I
44. termining the economic impact of a scheme using the outputs of a traffic model has been revised to allow annualisation factors to differ between input yearsand any alternate economic assessment methodology should follow this requirement Data from the initial assessment if available should be used to_inform_the preliminary choice of forecast years to be modelled The initialforecast yearssshould be the opening year of MM HSR and the intervening years betweenopening year and design year and between design year and final forecast year when there would be a significant change in the operation of MM HSR for example a change in the time periods over which MM HSR is expected to operate Forecast years should also cover other significant network changes such as major linkseaching capacity in line with WebTAG guidance The traffic model should be constructedto use this information and the MM HSR speed flow curve on the appropriate links to provide the output for the economic assessment The initial model should be built on an annual average weekday basis with at least the standard AM interpeak and PM time periods Nt is assumed that these would be modelled as average hours within their corresponding periods If the modelling is undertaken ona different basis advice should be sought from the HA TAME group Allowance is made withinFRIIT for the modelling of offpeak and weekend periods although it is acknowledged that mostsmodels are not created
45. the results should not be included in the Analysis of Monetised Costs and Benefits AMCB table 3 2 5 Details of what assumptions should be made in the assessment of the impact of MM HSR on journey time reliability are available from the HA TAME group TEE and Accident Impacts due to Maintenance and Construction 3 2 6 An assessment of the effects of changes in delay due to the construction and ongoing maintenance of MM HSR using the scheme model QUADRO or alternative similar assessment is mandatory for a full assessment 3 2 7 An outline of the additional maintenance required for an MM HSR scheme and the likely traffic management regime is included in Appendix E 3 2 8 During periods of maintenance the hard shoulder gives scope for areas of the normal running carriageway to be removed without loss of capacity Once MM HSR has been implemented this flexibility is not available during periods of high traffic flows which in addition to the possibly higher traffic flows under MM HSR may lead to an increase in delays during periods of maintenance Costs 3 2 9 Increased operational costs associated withMM HSR should be included in the scheme costs for the fullassessment including any extra staff costs resulting from additional monitoring by RTCC staff and an increased number of patrols by traffic officers Details of these costs can be obtained from the Managed Motorways Delivery Office Guidance on incorporating these costs in the
46. to cover these periods and therefore data requirements within the tool for these periods is optional It should be noted however thatwhere MM HSR is being considered against options that would be in place during the weekend such as full widening the weekend and potentially off peak periods must be considered in some manner and advice should be sought from the TAME group The process of creating an MM HSR model is illustrated in the flowchart at the end of this Appendix The following assumptions are key to the calculation of MM HSR benefits e There are no impacts on traffic on the network unless MM HSR is operating e Theshard shoulder has the same capacity as a normal lane and e The annualisation factors representing the proportion of the year that MM HSR is active will change in a linear fashion between modelled years Where throughyunction running TJR is to be provided between adjoining links it can be assumed that the hard shoulder is available through the junctions during hours when MM HSR is not in operation on the adjoining links in line with Interim Advice Note 112 It is however assumed that the actual impact on traffic of this assumption would be negligible during these periods and need not be explicitly modelled Since MM HSR is dynamic and is only active during portions of each time period in which flows exceed the threshold models based on the annual average time period IAN 159 12 Page 27 of 31 Aug 2012 Inte
47. ually calculated from the annual flow profiles entered and appropriate growth factors applied to these to provide future year flows This method is also appropriate where the weekend or offpeak has not been modelled and some indication is sought as to whether it may be appropriate to do so In this case the offpeak and weekend flows can be calculated in the base year from the flow profiles and then the growth observed in the interpeak period applied to produce future year flows IFRIIT also identifies the link that should be regarded as the constraining or control link s for each period and forecast year The control link can be defined as the link that determines whether an operational section of MM HSR links is active or not and is the link within the section with the highest annualisation factor The control link tends in most instances to be the link with the highest annual flow To create the models that represent the HSR on portions of each year the uplift factors should be applied to the Do Minimum and Do Something post VDM IAN 159 12 Page 28 of 31 Aug 2012 19 Interim Advice Note 159 12 Guidance Note for Traffic Consultants on the Economic Assessment of MM HSR Schemes variable demand modelling matrices These uplifted matrices should then be re assigned to the appropriate traffic models and the results passed through into the economic assessment As environmental assessments require data covering the whole year the HSR off
48. ulates a global matrix adjustment factor based upon the ratio between the average Do Something flow in the on periods to the annual average Do Something flow for each modelled time period and each forecast year This uplift factor will represent an increase to the number of trips in the matrix and is applied to the post variable demand model VDM Do Minimum and Do Something matrices to represent the busy portions of the year It is possible to calculate the uplift factor using alternate tools and the methodology of the calculation is outlined in Appendix G These matrices should then be assigned for each period and forecast year and the results used in TUBA or an alternate WebTAG compliant process together with the calculated annualisation factors to determine the TEE benefits for the scheme 3 1 10 It should be noted that for environmental assessment purposes it is necessary to obtain traffic flow forecasts for the whole year and not just for those portions of the year when HSR is likely to be switched on This means that forecasts also have to be prepared f r the portions of the year when HSR is likely to be switched off and this necessitates the production of adjusted model matrices that represent the average demands for those times in each forecast year when HSR is switched off 3 1 11 To facilitate this IFRIIT calculates a global matrix adjustment factor based upon the ratio between the average Do Minimum flow in the off periods to the annual
49. whether recoverable or not therefore there is no need for an adjustment as required by WebTAG All costs are in 2008 factor costs and the RPhfor 2008 is 214 8 8 The total expenditure andthe expenditure profile across the 60 year assessment period should be entered into TUBA from the table in the bottom right hand corner of theindividual scheme sheets the costs including cost reductions over time All thecosts should be entered into TUBA as Operating costs regardless of whether they come under the heading of Maintenance Operations or Renewals The costs should be entered_as costs in the Do Something only 9 As noted in WebTAG Unit 3 5 9 The Estimation and Treatment of Scheme Costs the capital costs of non traffic related maintenance e g drainage fencing grass cutting etc should appear in the Public Accounts table as operating costs as should the extra staffing in traffic control centres whilst the capital costs of traffic related maintenance e g resurfacing gantry maintenance etc should appear as investment costs IAN 159 12 Page 25 of 31 Aug 2012 IAN 159 12 Interim Advice Note 159 12 Guidance Note for Traffic Consultants on the Economic Assessment of MM HSR Schemes In order to represent these costs in the correct category the capital costs of non traffic related maintenance should be entered into TUBA as a Maintenance cost the additional operating costs should be included as Operating costs and the
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