2014 Detailed Air Quality Assessment for Greater Manchester The Greater Manchester Combined Authority 2014 Detailed Air Quality Assessment Greater Manchester © HaskoningDHV UK Ltd Document title: Detailed Air Quality Assessment Greater Manchester Status: Final Draft Date: September 2015 Project name: AGMA Detailed Assessment Project number: 9Y1637 Client: Association of Greater Manchester Authorities Reference: 9Y1637/R001/303345 Drafted by: Alice McLean Checked by: John Drabble Date / initials check: Approved by: John Drabble Date / initials approval: 2014 Detailed Air Quality Assessment Greater Manchester © HaskoningDHV UK Ltd Summary This Detailed Assessment for nitrogen dioxide (NO2) has been produced on behalf of the Association of Greater Manchester Authorities (AGMA) and the Greater Manchester Combined Authority (CA) who work in partnership to co- ordinate Local Air Quality Management for ten local authorities in Greater Manchester (Bolton, Bury, Manchester, Oldham, Rochdale, Salford, Stockport, Tameside, Trafford, and Wigan). The Greater Manchester CA has statutory powers for Local Air Quality Management (LAQM) under Sections 82 to 84 of the Environment Act 1995. The report provides a review of NO2 monitoring data from AGMA Authorities and presents results from the Greater Manchester Emissions Dispersion Model (GMEDIS) NO2 modelling study undertaken by Transport for Greater Manchester (TFGM), which is subject to a separate report. The Detailed Assessment follows a 2012 Updating and Screening Assessment (USA) for Greater Manchester, which was the first air quality assessment report of the Greater Manchester CA. The conclusions of the 2012 USA were that nitrogen dioxide measurements from a range of automatic stations in different districts showed broad agreement with the respective AQMA designations, but more widespread passive diffusion tube data suggested that the current AQMA required review. A comprehensive atmospheric emissions inventory for the Greater Manchester area was compiled at the onset of the LAQM regime, which has been revised and updated periodically since 1997. The latest version of the inventory was established on a base year of 2010 but incorporated road transport and industrial emission source projections to 2016, and this formed the basis of the predictive modelling study. The GMEDIS model results indicate that exceedences of the NO2 long and short term Objectives are unlikely outside the existing AQMA boundary. The highest concentrations of NO2 are predicted to be within the AQMA and in close proximity to motorways, major roads, town and city centres. The modelling results also indicate that NO2 concentrations have decreased across Greater Manchester since the AQMA was declared, with the existing AQMA boundary set at 35 μg.m-3 covering a much larger area than that predicted to exceed 35 μg.m-3 in 2016. The analysis of continuous and passive diffusion tube NO2 monitoring data over a 5-year period from 2009 to 2013, and a detailed predictive modelling study using a 2010 base year and a 2016 scenario, both indicate that the geographical extent of exceedences of the NO2 Objective has decreased since the latest Greater Manchester AQMA was designated. The conclusion is that the boundary will be reduced back to the key road network sources in accordance with the modelled concentrations. 2014 Detailed Air Quality Assessment Greater Manchester © HaskoningDHV UK Ltd Table of Contents Summary Summary ............................................................................................................................3 Table of Contents ..............................................................................................................4 1 Introduction .................................................................................................................1 1.1 Project Background ............................................................................................................................................2 1.2 Legislative Background ......................................................................................................................................2 1.2.1 European Standards for Air Quality....................................................................................................................2 1.2.2 National Legislation and Standards on Air Quality .............................................................................................2 1.2.3 Local Air Quality Management ...........................................................................................................................3 1.3 Greater Manchester Air Quality Management Area (AQMA)..............................................................................5 1.4 Summary of Greater Manchester Air Quality Review and Assessment..............................................................5 2 Methodology................................................................................................................6 2.1 Data Sources......................................................................................................................................................7 2.2 Greater Manchester Air Quality Monitoring ........................................................................................................7 2.3 Dispersion Modelling ..........................................................................................................................................7 2.3.1 Emissions modelled ...........................................................................................................................................8 2.3.2 Meteorological Data ...........................................................................................................................................8 2.3.3 Background Concentrations ...............................................................................................................................8 2.3.4 Emission Factors................................................................................................................................................8 2.3.5 Model Areas .......................................................................................................................................................8 2.3.6 Monin-Obukhov Length ......................................................................................................................................8 2.3.7 Surface roughness .............................................................................................................................................8 2.3.8 Conversion of NOx to NO2 ...................................................................................................................................9 2.3.9 Receptor Locations ............................................................................................................................................9 2.3.10 Model Uncertainty ..............................................................................................................................................9 2.3.11 Model Verification...............................................................................................................................................9 3 Greater Manchester Air Quality Monitoring............................................................10 3.1 Air Quality Monitoring .......................................................................................................................................11 3.1.1 Results from Automatic Monitoring Sites..........................................................................................................12 3.1.2 Results from NO2 Diffusion Tube Sites ............................................................................................................16 2014 Detailed Air Quality Assessment Greater Manchester © HaskoningDHV UK Ltd 4 Air Quality Modelling Results ..................................................................................21 4.1 Predicted NO2 concentrations at specified points.............................................................................................22 4.2 Predicted NO2 concentrations across Greater Manchester..............................................................................23 5 Conclusions ..............................................................................................................26 Appendix A.......................................................................................................................32 Appendix A: Monitoring Data Quality Assurance and Control ...............................................................................33 Appendix B.......................................................................................................................56 Appendix B: Model Uncertainty.................................................................................................................................57 Appendix B: Model Verification.................................................................................................................................60 Appendix B: Predicted NO2 concentrations 2010 and 2016..........................................................................................70 2014 Detailed Air Quality Assessment Greater Manchester © HaskoningDHV UK Ltd NOTICE This document and its contents have been prepared and are intended solely for