Background Quality water, sanitation, and hygiene facilities act as barricades to the transmission of COVID-19 in health care facilities. These facilities ought to also be available, accessible, and functional in temporary treatment centers. Despite numerous studies on health care facilities, however, there is limited information on the status of WASH facilities in such centers. Methods The assessment of health care facilities for the COVID-19 response checklist and key informant interviews, were used for data collection. 35 treatment centers in Southern Ethiopia were surveyed. Eightkey informants were interviewed to gain an understanding of the WASH conditions in the treatment centers. The Quantitative data was entered using EPI-INFO 7 and exported to SPSS 20 for analysis. Results are presented using descriptive statistics. Open Code 4.02 was used for the thematic analysis of the qualitative data. Results Daily water supply interruptions occurred at 27 (77.1%) of the surveyed sites. Only 30 (85.72%) had bathrooms that were segregated for personnel and patients, and only 3 (3.57%) had toilets that were handicapped accessible. 20(57.2%) of the treatment centers did not have a hand hygiene protocol that satisfied WHO guidelines. In terms of infection prevention and control, 16 (45.71%) of the facilities lacked adequate personal protective equipment stocks. Between urban and rural areas, there was also a significant difference in latrine maintenance, hand hygiene protocol design and implementation, and incineration capacity. Conclusion The results reveal crucial deficiencies in the provision of WASH in the temporary COVID-19 treatment centers. Efforts to improve WASH should offer priority to hygiene service interventions to minimize the risk of healthcare-acquired infections. The sustainable provision of hygiene services, such as hand washing soap, should also be given priority.