It makes senses that we should utilise this valuable natural resource.  In the most basic form of this technology, rainwater is collected in simple vessels at the edge of the roof. Variations on this basic approach include collection of large volumes of rainwater in gutters which drain to the collection vessel through down-pipes constructed for this purpose, and/or the diversion of rainwater from the gutters to containers for settling particulates before being conveyed to the storage container for the domestic use. 

Water can be filtered to a high standard and after months of storage tests concluded that the water remains oxygenated without the use of paddles or pumps.  The table below illustrates results of bacteriological and chemical analysis from harvested rainwater carried out by the HSE, deeming the water fit for human consumption.