Water content is determined by the Karl Fischer titration method and it consists of only water i.e moisture content. The results do not contain other volatile matter except the water.
Loss on drying (LOD) is determined by heating the sample below its melting point in an oven and it includes all volatile matter including water content and solvents. LOD is the loss on drying to test as per prescribed conditions which gives loss (presence) of all evaporating solvents.