Traffic congestion and rising vehicular pollution are considered to be among the major factors marring the environment in the once clean and green Dehradun.
Links:
[1] http://admin.indiaenvironmentportal.org.in/news/cycling-helps-keep-oneself-fit-curb-pollution
[2] http://admin.indiaenvironmentportal.org.in/category/author/sarthak-agarwal
[3] http://admin.indiaenvironmentportal.org.in/category/newspaper/pioneer-dehradun
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/uttaranchal-uttarakhand
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/dehradun-t
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/cycles
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/congestion
[8] http://admin.indiaenvironmentportal.org.in/category/thesaurus/vehicular-pollution
[9] http://admin.indiaenvironmentportal.org.in/category/thesaurus/two-wheelers
[10] http://admin.indiaenvironmentportal.org.in/category/thesaurus/transport