{"id":1886,"date":"2019-07-15T20:14:12","date_gmt":"2019-07-15T19:14:12","guid":{"rendered":"https:\/\/marriott-stats.com\/nigels-blog\/?p=1886"},"modified":"2019-09-16T15:10:48","modified_gmt":"2019-09-16T14:10:48","slug":"stats-in-the-news-3-bath-clean-air-zone-caz","status":"publish","type":"post","link":"https:\/\/marriott-stats.com\/nigels-blog\/stats-in-the-news-3-bath-clean-air-zone-caz\/","title":{"rendered":"Stats in the News #3 &#8211; Did I change Bath&#8217;s Clean Air Zone plans?"},"content":{"rendered":"<p>The city of Bath is among a number of cities in the UK tasked with reducing Nitrogen Oxide (<strong>NOx<\/strong>) emissions.\u00a0 NOx pollution is thought to contribute to poor health and the government has required clean air plans from the relevant local authorities to be in place before 2021.\u00a0 I had no idea that this would result in my statistical expertise being needed to answer a political row over the <a href=\"https:\/\/www.bathnes.gov.uk\/bath-breathes-2021-overview\" target=\"_blank\" rel=\"noopener noreferrer\">BathBreathes2021<\/a> plans to charge cars driving into Bath and you can read my report to see what my answer was!<\/p>\n<p><!--more--><\/p>\n<h4><span style=\"color: #008000\"><strong>BathBreathes2021<\/strong><\/span><\/h4>\n<p>In 2018, Bath &amp; North East Somerset (<strong>B&amp;NES<\/strong>) council announced their proposals for dealing with NOx emissions within the city of Bath.\u00a0 A website <a href=\"https:\/\/www.bathnes.gov.uk\/bath-breathes-2021-overview\" target=\"_blank\" rel=\"noopener noreferrer\">BathBreathes2021<\/a> was set up to provide the public with all the necessary information but the element that immediately caused controversy was B&amp;NES&#8217; proposal to implement a Class D charging scheme for certain vehicles driving into the Bath Clean Air Zone (<strong>CAZ<\/strong>).\u00a0 The government gave local authorities 4 options to choose from should they decide to charge vehicles which were:-<\/p>\n<ul>\n<li><strong>Class A<\/strong> &#8211; charge Buses, Coaches &amp; Taxis<\/li>\n<li><strong>Class B<\/strong> &#8211; charge Buses, Coaches, Taxis &amp; HGVs<\/li>\n<li><strong>Class C<\/strong> &#8211; charge Buses, Coaches, Taxis, HGVs &amp; LGVs<\/li>\n<li><strong>Class D<\/strong> &#8211; charge Buses, Coaches, Taxis, HGVs, LGVs &amp; Cars<\/li>\n<\/ul>\n<p>It should be noted that environmentally friendly vehicles of all types are exempt from charges since the purpose of the charging scheme is to encourage the vehicle owners to switch to lower emission vehicles.\u00a0 Still a number of private car owners would have been affected so it is no wonder that a political row began on the council.\u00a0 At the time, B&amp;NES was run by the Conservatives with the Liberal Democrats providing the main opposition.<\/p>\n<p>&nbsp;<\/p>\n<h4><span style=\"color: #008000\"><strong>How I got involved<\/strong><\/span><\/h4>\n<p>B&amp;NES had made their proposal based on Air Quality Modelling (<strong>AQM<\/strong>) undertaken by a specialist company.\u00a0 The AQM had compared the expected outcome in 2021 if no action was taken with the expected outcome in 2021 if either of the 4 options (A, B, C, D) were implemented.\u00a0 From this analysis B&amp;NES drew the following conclusion:<\/p>\n<p style=\"padding-left: 40px\"><em><strong>\u201c<\/strong><span style=\"color: #800000\">Our preferred option to achieve these improvements is a Class D Clean Air Zone (CAZ). This would mean charging drivers of all higher emission vehicles \u2013 including cars \u2013 to drive in the city centre from late 2020. Lower emission vehicles would not pay the charge. <\/span><\/em><\/p>\n<p style=\"padding-left: 40px\"><span style=\"color: #800000\"><em><strong>We also looked at other options, including not charging higher emission cars, but extensive analysis has shown that none of these options would enable us to meet the required reduction of NO2 in the time allowed.\u201d <\/strong><\/em><\/span><\/p>\n<p>A group of Conservative councillors had looked at the various scenarios produced by the AQM and they did not agree that a Class D CAZ was the only solution.\u00a0 They decided to approach me to provide an independent assessment of the publicly available information and I agreed to provide an expert opinion.\u00a0 Since this would involve assessing data produced by a forecasting model, and forecasting inevitably requires statistical modelling and interpretation, the councillors correctly identified that the expert had to be a professional statistician i.e. someone like me!<\/p>\n<p>&nbsp;<\/p>\n<h4><span style=\"color: #008000\"><strong>A report by an Independent Statistician<\/strong><\/span><\/h4>\n<p>I wrote my report in December 2018 and this was submitted to the public consultation that B&amp;NES were undertaking at the time.\u00a0 As this was a public document, there is no issue with me making it available here.\u00a0 Please click on the title below to read it in full (10 pages in total)<\/p>\n<p style=\"padding-left: 40px\"><strong><a href=\"https:\/\/marriott-stats.com\/nigels-blog\/wp-content\/uploads\/2019\/08\/Bath-CAZ-Options-Statistical-Opinion-of-Likely-Impacts.pdf\">Bath CAZ Options &#8211; A Statistical Opinion of Likely Impacts<\/a><\/strong><\/p>\n<p>The layout of this report is similar to many other reports I have written as an expert witness.\u00a0 The five section headings are:-<\/p>\n<ol>\n<li><em><span style=\"color: #008000\"><strong>Why I was asked to write this report<\/strong> <\/span><\/em>&#8211; A brief description of the background to the issue and the question(s) that I was asked to provide an expert opinion on.\u00a0 This section also lists my credentials as to why I am qualified to offer an expert opinion.<\/li>\n<li><em><span style=\"color: #008000\"><strong>Documents reviewed during the writing of this report<\/strong><\/span><\/em> &#8211; I consider it extremely important for the reader to be aware of what data and information I used to form my opinion and equally what data and information I did not use.\u00a0 In this instance, the number of documents on the BathBreathes2021 site was considerable but in the end I decided I could form an opinion with just 6 documents.<\/li>\n<li><span style=\"color: #008000\"><strong><em>My assessment of the Class C &amp; D CAZ options<\/em><\/strong><\/span> &#8211; the councillors who engaged me were happy to support a Class C CAZ but felt the evidence did not justify a class D CAZ.\u00a0 In this section, I commented on the available information for these two schemes as provided by the relevant AQMs.<\/li>\n<li><em><span style=\"color: #008000\"><strong>My Conclusions<\/strong> <\/span><\/em>&#8211; I concluded that the councillors were right i.e. B&amp;NES could not claim that only a class D scheme could meet government targets by 2021.\u00a0 It was clear to me from the available AQMs that a class C scheme could also meet government targets.<\/li>\n<li><span style=\"color: #008000\"><em><strong>Declarations of Interest<\/strong><\/em><\/span> &#8211; Since this was a public document that I had been paid to produce, I felt it was important to state all possible conflicts of interest though in the event, there were no conflicts at all.\u00a0 I also listed the professional standards which I am required to follow as an Independent Statistician.<\/li>\n<\/ol>\n<p>I hope you find this report of interest and it gives you a good idea of the kind of report you would receive from me should <a href=\"https:\/\/marriott-stats.com\/expert-witness\/\" target=\"_blank\" rel=\"noopener noreferrer\">you engage me as an expert witness in your case<\/a>.\u00a0 If you would like to contact me for an initial discussion, <a href=\"https:\/\/marriott-stats.com\/contact-us\/\" target=\"_blank\" rel=\"noopener noreferrer\">you can find my contact details here<\/a>.<\/p>\n<p>&nbsp;<\/p>\n<h4><span style=\"color: #008000\"><strong>What happened next in Bath?<\/strong><\/span><\/h4>\n<p>In March 2019, B&amp;NES changed their mind and conceded that a Class C CAZ was feasible for Bath.\u00a0 The council is currently preparing its final business case to be submitted to the government and if it is accepted, the scheme would commence in November 2020.\u00a0 One point to bear in mind is that in May 2019, the Liberal Democrats won outright control of the council for the first time ever.\u00a0 Prior to the election, they had expressed support for the Class D option so it is still possible that the final business case will be for a Class D zone.\u00a0 Should they make such a decision, I will happily state in public that they cannot use the available air quality modelling data made public to state that a class D will be better than a class C.\u00a0 There might be financial or political grounds for favouring a class D scheme over a class C but they cannot claim environmental grounds since the AQM data clearly states there is almost no difference in their impacts.<\/p>\n<p>&nbsp;<\/p>\n<p><span style=\"color: #800000\"><strong><em>Update 12th August 2019<\/em><\/strong><\/span> &#8211; The Lib Dem council has indeed announced a review of the Class C proposal! See this article from <a href=\"https:\/\/www.somersetlive.co.uk\/news\/somerset-news\/new-look-bath-clean-air-3188517\" target=\"_blank\" rel=\"noopener noreferrer\">my local paper Bath Chronicle<\/a>.\u00a0 Let&#8217;s see if I need to get involved in local politics!<\/p>\n","protected":false},"excerpt":{"rendered":"<p>The city of Bath is among a number of cities in the UK tasked with reducing Nitrogen Oxide (NOx) emissions.\u00a0 NOx pollution is thought to contribute to poor health and the government has required clean air plans from the relevant local authorities to be in place before 2021.\u00a0 I had no idea that this would [&hellip;]<\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_genesis_hide_title":false,"_genesis_hide_breadcrumbs":false,"_genesis_hide_singular_image":false,"_genesis_hide_footer_widgets":false,"_genesis_custom_body_class":"","_genesis_custom_post_class":"","_genesis_layout":"","footnotes":""},"categories":[6,1],"tags":[121,36,120,25,118,119],"class_list":{"0":"post-1886","1":"post","2":"type-post","3":"status-publish","4":"format-standard","6":"category-forecasting","7":"category-misc","8":"tag-bathbreathe2021","9":"tag-evidence","10":"tag-expert-witness","11":"tag-forecasting-model","12":"tag-pollution","13":"tag-spatial-statistics","14":"entry","15":"override"},"_links":{"self":[{"href":"https:\/\/marriott-stats.com\/nigels-blog\/wp-json\/wp\/v2\/posts\/1886","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/marriott-stats.com\/nigels-blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/marriott-stats.com\/nigels-blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/marriott-stats.com\/nigels-blog\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/marriott-stats.com\/nigels-blog\/wp-json\/wp\/v2\/comments?post=1886"}],"version-history":[{"count":7,"href":"https:\/\/marriott-stats.com\/nigels-blog\/wp-json\/wp\/v2\/posts\/1886\/revisions"}],"predecessor-version":[{"id":1966,"href":"https:\/\/marriott-stats.com\/nigels-blog\/wp-json\/wp\/v2\/posts\/1886\/revisions\/1966"}],"wp:attachment":[{"href":"https:\/\/marriott-stats.com\/nigels-blog\/wp-json\/wp\/v2\/media?parent=1886"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/marriott-stats.com\/nigels-blog\/wp-json\/wp\/v2\/categories?post=1886"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/marriott-stats.com\/nigels-blog\/wp-json\/wp\/v2\/tags?post=1886"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}