Christchurch smog worst in Canterbury

Christchurch is heading the smog table in Canterbury this year, chalking up 17 high pollution nights to Timaru's 16.

Tuesday's smog pollution level in Christchurch was 2 1/2 times the recommended limit - reaching a 24-hour average concentration of 124 micrograms of suspended particulate per cubic metre of air.

Kaiapoi recorded its 11th high pollution night on Tuesday and Rangiora has had two high pollution nights. Outside Canterbury, Nelson has topped guidelines on 41 days this year.