The COVID-19 pandemic has caused many countries to close their borders, and large numbers of people have begun to spend their holidays and vacation time within their own countries rather than traveling abroad. This study assesses the impact of the pandemic on water consumption and wastewater generation in a popular tourist Aegean city (Bodrum, Turkey) and its suburbia where many visitors moved in to live there for an unforeseen future. The effects of the COVID-19 pandemic on water consumption within the residential and commercial areas showed a significant decrease in water consumption in commercial areas (%23) and an increase in the residential areas (%15) during the pandemic period. The wastewater in residential areas had to be treated in many on-site wastewater treatment plants, apart from the central treatment plants which may pose a risk to the groundwater and surface water resources of the region. This shows that the treatment technologies and capacities of wastewater treatment plants need to be revised for situations such as unexpected pandemics.