In the early hours of 14 August, after three days of torrential rainfall, a hill located near the pumping station of Regent area in the heights around Sierra Leone’s capital Freetown – around 500 metres above sea level – partly collapsed and triggered a devastating mud and rockslide. As of 20 August, the number of confirmed deaths is 499, while hundreds are missing. Thousands of people have been displaced and hundreds of buildings were damaged or destroyed by the mudslides. MSF teams carried out detailed assessments of all affected communities in the small but densely-populated river valley, from the location of the landslide down to the ocean at the southern side of Freetown. The MSF teams identified the communities in most urgent need of water and sanitation assistance, based on population density, level of displacement, lack of clean water supply and lack of sanitation facilities. The communities in Kamayama, Jah Kingdom, and Mortome were identified to have the biggest needs, including being vulnerable to further flooding or land instability. In the immediate term, MSF will focus on ensuring people have access to clean water and sanitation facilities, as this is crucial both for meeting people’s urgent needs, as well for preventing epidemics of diseases such as malaria and cholera. MSF is preparing to respond in the event of such an outbreak, however ensuring people have clean water, sanitation, adequate shelter and medical care, is the best way to prevent this from happening.