Barbados is susceptible to environmental pressures. As one of the world's most densely populated isles, the government worked during the 1990s to aggressively integrate the growing south coast of the island into the Bridgetown Sewage Treatment Plant to reduce contamination of offshore coral reefs. As of the first decade of the 21st century, a second treatment plant has been proposed along the island's west coast. Being so densely populated, Barbados has made great efforts to protect its underground aquifers.