kilometres in length, have their headwaters in Fairfield City and flow into the Georges River and Hawkesbury Nepean catchments. The impact of development over the past 50 years has resulted in severe degradation of the natural habitat in the creek banks and water quality has been assessed as very poor in recent years. Strategies are being implemented so that this trend is being reversed. Air quality in the city is heavily impacted upon by an insufficiently integrated public transport system, creating an over reliance upon private vehicles for moving people and freight. Climate Fairfield has a humid subtropical climate (Köppen climate classification: Cfa). Summer weather may come from north-east (humid) or the north west (dry). Fairfield is usually a few degrees warmer than Sydney on summer days and a few degrees cooler on winter nights. There could be a temperature differential of 5 degrees Celsius in summer due to sea breezes in the City that don't generally penetrate inland, and in extreme cases there could be a 10 degrees differential. It receives less annual rain than Sydney CBD by about 400mm. Late winter and early spring receive the least rainfall, whilst late summer and autumn receive more rain. Demographics According to the 2021 census, the suburb of Fairfield had a population of 18,596 people, the majority of whom (67.3%) were born outside of Australia. Country of birth The largest groups were born in Iraq (22.6%), Vietnam (9.8%), Syria (8.3%), China (2.7%) and Cambodia (2.1%). Languages Only 16.0% of people spoke English as their only home language. The most common language spoken other than English is Arabic at 16.7% (mostly Iraqi Arabic and Syrian Arabic), Assyrian Neo-Aramaic at 15.2%, Vietnamese at 12.0%, Chaldean Neo-Aramaic at 5.9% and Mandarin at 3.0%. If the Assyrian and Chaldean varieties were combined, then Neo-Aramaic will be the most common language at 21.1%. Ethnicity The most common ethnic groups were Assyrian (15.5%), Vietnamese (11.2%), Chinese (10.2%), Iraqi (10.1%) and Australian (6.9%). Religion The top responses for religious affiliation were Catholic (31.1%), No Religion (11.8%), Buddhism (11.7%), and Islam (8.5%). Christianity was the largest religious group reported overall (61.8%). Families 47.2% were couple families with children, 24.9% were couple families without children and 24.6% were one parent families. Of people over 15 years, 45.5% were married and 13.3% were either divorced or separated. Of all households, 74.4% were family households, 23.1% were single person households and 2.4%