We studied the coastal waters of Vieques, Puerto Rico, looking at fish and bottom-dwelling animals, contaminants in sediments and corals, and nutrient levels in surface waters. We also mapped the ocean floor surrounding the island. We confirmed the area was safe for the residents to return by determining that the environmental quality of Vieques’ coastal waters is similar to that of other areas of the Caribbean.

Why We Care
From 1941 to 2003, the U.S. Navy conducted live bombing exercises on the eastern side of the island of Vieques, Puerto Rico. As the Navy phased out operations and the land-transfer process began, we completed an assessment of the site’s marine resources to ensure the safety of civilian residents wishing to move to the area and establish tourism locally. They needed to know the extent and location of significant contamination.

What We Found
At 4 of the 78 sites tested, we found DDT, an insecticide banned in 1972 that is toxic to animals and humans, at a level above accepted guidelines. At one site, we detected chromium, a heavy metal that can be toxic to both fish and humans, at a level above established guidelines. We detected no explosive compounds, such as TNT.

Overall, we found that nutrients, the condition of fish populations, and coral reef ecosystem conditions around Vieques were comparable to those of other coral reef ecosystems in Puerto Rico and the U.S. Virgin Islands. Their condition appeared to be shaped primarily by regional-scale processes, such as nutrient enrichment and overfishing, rather than local factors.

What We Did
We characterized the coral reef ecosystems, contaminants, and nutrient distribution patterns around Vieques. Our tests, which covered the island’s near-shore waters and inland lagoons, covered 162 contaminants, including heavy metals, explosives, pesticides, hydrocarbons, and other pollutants.

Next Steps
This assessment is complete. The U.S. Navy, the U.S. Fish and Wildlife Service, environmental managers, local government, and the people of Puerto Rico have access to our report and can use it to better understand how to protect and restore the marine environment of Vieques. We are ready to continue working in the region if requested.