City report · Île-de-France, France
Saint-Quentin-en-Yvelines Air quality today
Air quality in Saint-Quentin-en-Yvelines currently reads AQI 36 (Good): Air quality is satisfactory for everyone.
AQI 36
Air quality right now
Good
- PM2.5, fine particles (µg/m³)
- 6.4
- tree cover
- 47.8%
- trees in this area
- 140K
- more trees needed
- 0
Measured across a 2 km radius around Montigny-le-Bretonneux, France (12.57 km²), from a satellite image of Sep 14, 2026. Lower AQI is better: 0–50 is Good, above 300 is Hazardous.
Saint-Quentin-en-Yvelines · AQI 36 (Good)
Saint-Quentin-en-Yvelines's tree count comes to 140,107 trees across 11.73 km² of land, already at or above the 30% tree-cover level considered healthy for this area.
Air quality detail
Air quality in Saint-Quentin-en-Yvelines today: AQI 36, Good
Main pollutant: PM2.5 · Observed Nov 11, 17:00 local time via OpenAQ ground stations, US EPA index. Values in µg/m³.
Ground station · LA DEFENSE, 21 km away · median of 10 stations
Health signal
Air quality is satisfactory for everyone.
PM2.5
6.4
PM10
7.7
NO₂
15.4
O₃
55.4
SO₂
—
CO
—
Data: OpenAQ · EEA
- Outdoor exercise
- A good day to be active outside
- Windows
- Open them to air the house
- Mask
- Not needed
- Air purifier
- Not needed
Over the last 7 days, the CAMS air-quality model put Saint-Quentin-en-Yvelines's daily AQI at 71 on average, from 58 on Nov 4 to an hourly peak of 102 on Nov 7.
Where Saint-Quentin-en-Yvelines stands: the most polluted cities in the world right now · the cleanest
Tree cover detail
Tree cover in Saint-Quentin-en-Yvelines: Healthy tree cover
47.8% tree cover against a 30% healthy-neighborhood target, across 11.73 km² of land.
Trees in this area
140,107
Target trees
140,107
More trees needed
0
CO₂ if planted / yr
0 kg
Deforestation · 2001–2025
How much forest has Saint-Quentin-en-Yvelines lost?
Since 2001, the area within 10 km of Saint-Quentin-en-Yvelines has lost about 270 hectares of forest (about 380 football pitches): 2.7% of the forest it had in 2000. Most of it was lost to logging, so much of it can grow back. About 115 hectares (42%) was deforestation: forest cleared for good for farms, mines or towns.
2017: satellite photo from August 2017 of a 5 × 5 km area in the city center.
- Forest lost since 2001
- 270 haabout 380 football pitches
- Share of its forest
- 2.7%of what there was in 2000
- Cleared for good
- 115 hadeforestation: turned into farms, mines or towns
The worst year was 2008, when about 37 hectares of forest were lost.
Hectares of forest lost each year
Show the figures as a table
| Year | Cleared for good | Can grow back | Total |
|---|---|---|---|
| 2001 | 17 ha | 15 ha | 31 ha |
| 2002 | 5 ha | 9 ha | 13 ha |
| 2003 | 2 ha | 5 ha | 6 ha |
| 2004 | 4 ha | 7 ha | 11 ha |
| 2005 | 5 ha | 12 ha | 16 ha |
| 2006 | 3 ha | 2 ha | 5 ha |
| 2007 | 3 ha | 3 ha | 7 ha |
| 2008 | 11 ha | 26 ha | 37 ha |
| 2009 | under 1 ha | 1 ha | 2 ha |
| 2010 | 4 ha | 21 ha | 25 ha |
| 2011 | 15 ha | 4 ha | 19 ha |
| 2012 | 4 ha | 10 ha | 15 ha |
| 2013 | under 1 ha | under 1 ha | 2 ha |
| 2014 | 1 ha | under 1 ha | 2 ha |
| 2015 | under 1 ha | under 1 ha | 1 ha |
| 2016 | 1 ha | under 1 ha | 2 ha |
| 2017 | 2 ha | 4 ha | 6 ha |
| 2018 | 4 ha | 6 ha | 9 ha |
| 2019 | 2 ha | 2 ha | 4 ha |
| 2020 | 2 ha | 3 ha | 5 ha |
| 2021 | 2 ha | 3 ha | 5 ha |
| 2022 | 3 ha | 3 ha | 6 ha |
| 2023 | 13 ha | 6 ha | 19 ha |
| 2024 | 10 ha | 12 ha | 22 ha |
| 2025 | under 1 ha | under 1 ha | 1 ha |
What is causing deforestation around Saint-Quentin-en-Yvelines?
- Loggingcan grow back51% · 138 ha
- Towns and roadscleared for good42% · 113 ha
- Unknown causescause unknown6.8% · 18 ha
Also: farms, pasture and plantations.
Causes for 2025 are estimates, based on what caused forest loss in the same places up to 2024.
Forest gained and lost, 2000–2020
- Forest in 2000
- 12,700 ha
- Forest in 2020
- 13,100 ha
- Overall change
- +345 hamore forest than in 2000
Comparing satellite maps from 2000 and 2020, the forest around Saint-Quentin-en-Yvelines grew from about 12,700 hectares to 13,100 hectares, a net gain of about 345 hectares (+2.7%). New forest grew on about 537 hectares, while 192 hectares were lost.
These 2000 and 2020 maps, from the University of Maryland, count any land with trees taller than 5 m as forest, including plantations and orchards. Forest that was cut or burned and had grown back by 2020 counts in both years, so the loss here is smaller than the yearly figures.
These figures cover everything within 10 km of the city center, a wider area than the report above, because forest is usually lost at a city's edges.
Source: Hansen/UMD/Google/USGS/NASA, Global Forest Change (GFC-2025-v1.13); causes: WRI/Google DeepMind drivers of forest loss; both CC BY 4.0, summed by Airleaf for each area. Forest gained and lost 2000–2020: Potapov et al. 2022, UMD GLAD Global Land Cover and Land Use Change, CC BY 4.0. Images: contains modified Copernicus Sentinel data. How it's measured
In the same region
Measured cities near Saint-Quentin-en-Yvelines
Same 2 km radius, same index — so they compare directly.
- Boulogne-Billancourt17.8 km
France
- Tree cover
- 30%
- Air quality
- 35
- Argenteuil25.7 km
France
- Tree cover
- 24%
- Air quality
- 32
- Paris25.8 km
France
- Tree cover
- 13%
- Air quality
- 35
- Cergy-Pontoise30.0 km
France
- Tree cover
- 42%
- Air quality
- 28
- Marne La Vallée46.2 km
France
- Tree cover
- 39%
- Air quality
- 36
- Orléans97.0 km
France
- Tree cover
- 23%
- Air quality
- 31
Build your own
Compare Saint-Quentin-en-Yvelines with anywhere
This place
Saint-Quentin-en-Yvelines
Use this data
Put Saint-Quentin-en-Yvelines's numbers on your site
Free to embed. Updates itself as the measurement refreshes.
Frequently asked
Questions about Saint-Quentin-en-Yvelines
What is the air quality (AQI) in Saint-Quentin-en-Yvelines right now?
The latest reading for Saint-Quentin-en-Yvelines shows an AQI of 36 (Good), measured Nov 11, 17:00 local time by 10 ground monitoring stations via OpenAQ (the median of their readings; the nearest is LA DEFENSE, 21 km away). The main pollutant is PM2.5. Air quality is satisfactory for everyone.
Is it safe to exercise outside in Saint-Quentin-en-Yvelines today?
At AQI 36 (Good): a good day to be active outside. Windows: open them to air the house. Masks: not needed. The reading changes through the day, so check again before a long run or ride.
What has the air quality in Saint-Quentin-en-Yvelines been like this week?
Over the last 7 days, the CAMS air-quality model put Saint-Quentin-en-Yvelines's daily AQI at 71 on average, from 58 on Nov 4 to an hourly peak of 102 on Nov 7. No day averaged above 100, the level where the air turns unhealthy for sensitive groups.
How much forest has the area around Saint-Quentin-en-Yvelines lost since 2001?
Since 2001, the area within 10 km of Saint-Quentin-en-Yvelines has lost about 270 hectares of forest (about 380 football pitches): 2.7% of the forest it had in 2000. Most of it was lost to logging, so much of it can grow back. About 115 hectares (42%) was deforestation: forest cleared for good for farms, mines or towns. Comparing satellite maps from 2000 and 2020, the forest around Saint-Quentin-en-Yvelines grew from about 12,700 hectares to 13,100 hectares, a net gain of about 345 hectares (+2.7%). New forest grew on about 537 hectares, while 192 hectares were lost.
What is the tree count in Saint-Quentin-en-Yvelines?
Saint-Quentin-en-Yvelines has an estimated 140,107 trees across the 11.73 km² of land measured — 47.8% tree cover, already past the 30% tree-cover target set for this area.
How many more trees does Saint-Quentin-en-Yvelines need?
Saint-Quentin-en-Yvelines has already reached its tree-cover target, so no additional trees are needed to close the gap.
How are Saint-Quentin-en-Yvelines's air quality and tree cover measured?
Air quality is measured by ground monitoring stations near Montigny-le-Bretonneux, via OpenAQ; the 7-day trend is the Open-Meteo / CAMS model's estimate. Tree cover is measured from Sentinel-2 L2A (ESA Copernicus) via Earth Search satellite imagery at 10 m detail across a 2 km radius around Montigny-le-Bretonneux; the tree count is an estimate derived from that cover.
See your own area
What does your neighborhood look like?
Pick any point and radius to get the same air-quality and tree-cover breakdown.
Check my address