According to the present invention, a water absorbent material and materials to be sucked included in a water permeable bag type member form a water absorber. Thus, the water absorber is small both in weight and volume upon its transportation, and accordingly, the water absorber can be rapidly conveyed in large quantities without depending on a human power. The water absorber absorbs water upon its use to adequately satisfy a function of a form traceability for weight, volume and outline.