Question 1

What is the population of Guyancourt?

Accepted Answer

The commune of Guyancourt has 29,758 inhabitants per the INSEE census.

Question 2

Are there natural risks in Guyancourt?

Accepted Answer

Yes, Guyancourt is exposed to 1 natural risk(s): Transport de marchandises dangereuses. Source: Géorisques / GASPAR.

Question 3

What is the energy performance of homes in Guyancourt?

Accepted Answer

Out of 994 ADEME EPCs available in Guyancourt, the most common label is D. 0% are rated A or B.

Question 4

What is the crime rate in Guyancourt?

Accepted Answer

In 2025, the crime rate in Guyancourt was 27.8 offences per 1,000 inhabitants (burglaries, theft, violence, vandalism). Source: SSMSI / French Ministry of the Interior.

Question 5

Is the tap water safe to drink in Guyancourt?

Accepted Answer

Tap water in Guyancourt is compliant with quality standards. Source: ARS / Hub'eau. (675 analyses over 12 months)

Question 6

What is the air quality in Guyancourt?

Accepted Answer

According to LCSQA stations (5-year mean) in Guyancourt: PM2.5 : 11.0 µg/m³, NO₂ : 18.9 µg/m³, PM10 : 21.1 µg/m³. Source: LCSQA / Géod'air.