Existing climate scenarios show that in the future we will have longer dry periods and more intense rainfall, which increases the vulnerability of our systems for drinking water supply and sewage management. Islands are sensitive to coming climate change as they have small water resources and rarely have a municipal water supply. Today's water systems are linear, where purified wastewater is returned directly to nature. To get sustainable sewage management can a water use be introduced that mimics the hydrological cycle. The purpose of the study is to investigate the water supply, water and sewage system, attitude to reuse wastewater, as well as whether circular aquaculture is a sustainable system in developing counties.The results indicate that islanders generally manage their water resources and that a dubious attitude to reusing black water may be due to the so-called disgust factor. Despite a varying acceptance of reusing water, more should circular water systems can be introduced on the island, which gives developing countries more sustainable management of their wastewater.