TSFs are designed and constructed to store both tailings and water. The dam construction methods include two main types: (1) water retention dams and (2) progressively raised embankments. Water retention dams are typically constructed to their full height prior to anything being stored upstream and raised embankments are progressively raised in a vertical manner over time to store additional material. Raised embankments are the most commonly used method for TSFs. The raised embankment design methods for TSFs are typically downstream, upstream or centerline. This designates the direction in which the embankment crest moves in relation to the starter dam (dyke). Modified centerline is a construction method combining both upstream and centerline.