) Police Stations ( 2 ) Recycling Centres ( 3 ) Schools and Colleges ( 42 ) Population 20'417 (ONS Census 2001) OS grid reference TL116002 District Watford Shire county Hertfordshire Region East Constituent country England Sovereign state United Kingdom Post town WATFORD Postcode district WD25 Dialling code 01923 Police Hertfordshire Fire Hertfordshire Ambulance East of England European Parliament