SmogRank / Castlegar / Shawinigan

Castlegar vs Shawinigan: PM2.5 compared

Over the last year, Castlegar's air was about 1.7× as polluted as Shawinigan's: PM2.5 averaged 11.1 µg/m³ against 6.6, on the 319 days both cities were measured. Castlegar had the dirtier air on 198 of those days, Shawinigan on 118. Castlegar was over the WHO's daily guideline of 15 µg/m³ on 39 of them, Shawinigan on 8.

Right now

Castlegar#770on the 24-hour board of 2,002, at 45 US AQI (8.1 µg/m³)
Shawinigan#1,882on the 24-hour board of 2,002, at 14 US AQI (2.5 µg/m³)

The last year, day by day

Castlegar
Shawinigan
Each city's daily mean from 7 Oct 2025 to 6 Oct 2026, one stripe a day, coloured by band. A blank stripe is a day without a daily mean.

Month by month

Castlegar, Nov 2025: 9.2 µg/m³Shawinigan, Nov 2025: 4.7 µg/m³Nov2025Castlegar, Dec 2025: 6.3 µg/m³Shawinigan, Dec 2025: 6.3 µg/m³DecCastlegar, Jan 2026: 8.4 µg/m³Shawinigan, Jan 2026: 9.1 µg/m³Jan2026Castlegar, Feb 2026: 6.1 µg/m³Shawinigan, Feb 2026: 7.5 µg/m³FebCastlegar, Mar 2026: 6.2 µg/m³Shawinigan, Mar 2026: 5.8 µg/m³MarCastlegar, Apr 2026: 6.5 µg/m³Shawinigan, Apr 2026: 5.2 µg/m³AprCastlegar, May 2026: 5.9 µg/m³Shawinigan, May 2026: 4.7 µg/m³MayCastlegar, Jun 2026: 4.5 µg/m³Shawinigan, Jun 2026: 7.3 µg/m³JunCastlegar, Jul 2026: 19.7 µg/m³Shawinigan, Jul 2026: 11.4 µg/m³JulCastlegar, Aug 2026: 39.3 µg/m³Shawinigan, Aug 2026: 8.0 µg/m³AugCastlegar, Sep 2026: 8.0 µg/m³Shawinigan, Sep 2026: 5.3 µg/m³SepOct
Monthly means in µg/m³ over the days both cities were measured. Solid: Castlegar. Faded: Shawinigan. A month shows once both share 10 such days. Dashed line: the WHO daily guideline, 15 µg/m³.

Year by year

YearCastlegarShawiniganDays both measuredDays Castlegar was worse
2026 so far5739242144
20254240340191
20244036358198
20235248265150

Means in US AQI over the days both cities were measured that year; a year shows once they share 30 such days.

Each city's worst days

Castlegar

Shawinigan

Daily means in US AQI, with µg/m³ beside them, since the index stops at its top value, over the days both cities were measured in the last year. Each date opens that day's world board.

Compare either city with another

Castlegar

Side by side with Creston (the nearest), Edmonton (Canada's 2nd worst on 30 days), Gujranwala (the world's worst on 30 days).

Shawinigan

Side by side with Trois-Rivières (the nearest), Gujranwala (the world's worst on 30 days).

Use this page

SmogRank, PM2.5 daily means compared, Castlegar and Shawinigan, 7 Oct 2025 – 6 Oct 2026, smogrank.com/compare/ca-castlegar/ca-shawinigan (accessed 7 Oct 2026).

You're welcome to reuse a single chart, image or figure with this citation and a link. Terms. Raw monitor readings in bulk are published by OpenAQ, under each provider's licence.

The same rules as every SmogRank figure: reference monitors first, and a day counts with 18 measured hours. How we measure.

Updated 2026-10-07 08:07 UTC. Values are PM2.5 (fine particles), the median of each city's monitors, as the US AQI PM2.5 sub-index.