Through the integrated combination of storing, retaining and reusing water within an area, regions will be able to offset the ever-growing problem of water shortages and flooding. To achieve this, however, the water must be of good quality. As water storage is often carried out in both former and current agricultural areas, the objectives for water quality and nature are often not met. Biocascade water purification helps to retain or improve the water quality during storage and retention, and ensures that the water can be reused safely during dry periods. In addition, biocascade purification also provides opportunities to produce biomass for biobased applications.