Hydraulic fill is comparable to other construction materials in the sense that both the composition of the mix and the placement method affect the properties of the material and therefore must be designed so that the fill performs satisfactorily. However, it is necessary to understand the factors that influence the behaviour of hydraulic fills in order to design it properly. An experimental approach was adopted including laboratory flume deposition tests and large scale field deposition tests. Three different sands were used for the flume tests which studied the effect of slurry concentration, flow rate and mean grain size on the properties of the fill such as: geometry, density, grain size distribution and fabric. Eight large scale field tests were carried out on a tailings dam to study the deposition process and the effect of the placement method on the fill characteristics (geometry, density, grain size distribution, fabric and fines capture). An instability of the deposition process was observed in the field and its potential causes and consequences were discussed, showing the importance of having relatively constant feed parameters. A comparison between flume tests and field tests results proved that flume tests are a valuable tool in the study of hydraulic fills. The results of the flume and field tests showed a consistent trend of fill slopes becoming steeper as the discharge flow rate increased and as the slurry concentration and mean grain size increased. These conclusions are consistent with observations of other hydraulic fills and natural alluvial deposits. An empirical method of estimating beach slopes based on the discharge parameters is proposed. The trend of variation of density with the discharge parameters is discussed and the mean density values for the field tests are compared with the steady state line for the material deposited. A sedimentologic approach to the analysis of density of hydraulic fills is discussed. It is suggested that a boundary between the hydraulics of the flow and the geotechnical behaviour of the fill might be on the study of bedforms as they relate the flow energy to the formation of different deposits.