The island of Malé is the eighth most densely populated island in the world, and it is the 160th most populous island in the world. Since there is no surrounding countryside, all infrastructure has to be located in the city itself. Water is provided from desalinated ground water; the water works pumps brackish water from  deep wells in the city and desalinates that using reverse osmosis. Electric power is generated in the city using diesel generators. Sewage is pumped unprocessed into the sea. Solid waste is transported to nearby islands, where it is used to fill in lagoons. The airport was built in this way, and currently the Thilafushi lagoon is being filled in.