What is the ruling on constructing swimming pools, fountains, and artificial waterfalls, and what is the ruling on the water used therein? Is this considered extravagance?

It is permissible to build swimming pools, waterfalls, and fountains for benefit and beautification, and this is not considered extravagance, especially if undertaken by a governmental entity. The water used in them is not wasteful, because swimming necessitates filling the pool, while observing Sharia regulations such as avoiding nudity and intermingling, and not being distracted by them from acts of worship. The water in fountains and waterfalls circulates, so it is not consumed excessively. This water is pure unless it changes due to impurity.