WILLEMSTAD – Curaçao’s coastal waters are being affected by widespread pollution, including sewage, nutrients, chemicals, heavy metals and pathogens, according to the report State of Curaçao’s Coral Reefs 1973–2045.
The report states that pollution is highest near Willemstad, where around 50 sewage overflow points can release sewage and other pollutants into coastal waters, especially after heavy rainfall. However, the problem does not remain local. Currents can carry pollutants from the Willemstad area toward Westpunt within a day, spreading the impact across much of the island’s leeward coast.
The report says only about 30 percent of households are connected to the sewer system, while municipal sewage treatment plants treat less than half of incoming flow. As a result, untreated or insufficiently treated wastewater enters the marine environment through direct discharge, runoff and groundwater.
Groundwater pollution is also a major concern. According to the report, 36 percent of Curaçao’s groundwater consists of raw sewage from leaking cesspits and dysfunctional sewage infrastructure. E. coli was detected in 78 percent of sampled wells between 2021 and 2023, making that water unsuitable for consumption.
The consequences go beyond coral reefs. Polluted groundwater and coastal water can affect seagrass beds, mangroves, fish nursery areas, recreational waters and public health. The report warns that untreated wastewater introduces nutrients, pathogens and organic micropollutants into the marine environment.
Nutrient pollution contributes to eutrophication, a process that can turn clear tropical water green, stimulate algal blooms and smother corals. The report states that safe nutrient limits for tropical coastal waters have been frequently exceeded in Curaçao for decades.
Researchers also found concerns related to microbial pollution. Pathogenic microbes, including antibiotic-resistant bacteria, have been detected in recreational waters. The report warns that Curaçao’s coastal waters may act as a reservoir for microbes resistant to multiple antibiotics, including last-resort options.
The findings challenge the common belief that most marine pollution comes from outside Curaçao. While some plastics and tar may arrive from elsewhere, the report concludes that most water-quality pollution along the leeward coast is local in origin.
The report makes clear that improving wastewater management is one of the most important steps Curaçao can take to protect its reefs, public health and tourism economy.