Rupat is an island in the Strait of Malacca, and forms part of Bengkalis Regency within Riau, Indonesia. It lies just off the eastern coast of Sumatra, across from Dumai city, from which it is separated by the Rupat Strait. Its area is 1,704.98 km². The island is sparsely populated, with a population density of 36 per km². Rupat was one of thousands of aba…Rupat is an island in the Strait of Malacca, and forms part of Bengkalis Regency within Riau, Indonesia. It lies just off the eastern coast of Sumatra, across from Dumai city, from which it is separated by the Rupat Strait. Its area is 1,704.98 km². The island is sparsely populated, with a population density of 36 per km². Rupat was one of thousands of abandoned islands, but its population is growing yearly, which has made the government expand the area for the settlement.