Roads had spartse traffic due to the ban on entry of private vehicles during the 'Invest Karnataka-2016' summit. Pollution levels also came down due to the restriction.
Links:
[1] http://admin.indiaenvironmentportal.org.in/news/drop-pollution-levels-during-investors-meet-says-kspcb-report
[2] http://admin.indiaenvironmentportal.org.in/category/newspaper/deccan-herald-bangalore
[3] http://admin.indiaenvironmentportal.org.in/category/thesaurus/karnataka
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/air-pollution
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/bangalore-t
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/vehicular-pollution
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/air-pollution-control
[8] http://admin.indiaenvironmentportal.org.in/category/thesaurus/state-pollution-control-board-spcb-0
[9] http://admin.indiaenvironmentportal.org.in/category/thesaurus/nitrogen-dioxide
[10] http://admin.indiaenvironmentportal.org.in/category/thesaurus/noise-pollution