MANILA - The government is temporarily banning water activities in Boracay to check the island's marine biodiversity and "to lengthen the beach and swimming area for tourists," an Environment official said Friday.

Officials are in the process of completing a "biodiversity assessment" to designate marine sanctuaries, and "regulate water sue zones" for water sports activities and swimming, Environment Undersecretary Sherwin Rigor told reporters.

"The purpose of this is to lengthen the beach and swimming area for tourists," he said.

"In the near future we want to increase the carrying capacity based on the increase of our swimming area," he said.

Rigor said the 30-meter no build-zone policy along the beach, including a regulation on sandcastle making, will also be strictly implemented to ensure that there will be more space for beach goers.

"This is to regulate sand castle making para hindi masyadong malaki, para hindi makabawas sa carrying capacity," Rigor said.

"Ito kasi ay nakakaistorbo sa ating tourists and sometimes they are being used for entrepreneurial activities," he said.

Boracay started a "dry run" of its new rules on Monday to allow locals to adjust to the new policies before the island's expected reopening on October 26.

Boracay was closed to tourists last April for a half-year rehabilitation after President Rodrigo Duterte said the island's waters have turned into "cesspools."