The Clean Water goal captures the degree to which local waters are unpolluted by human-made causes.


People value marine waters that are free of pollution and debris for aesthetic and health reasons.

Chemicals, excess nutrients, pathogens, and trash that enter the marine environment can harm human health, livelihoods, and recreation, as well as the health of marine life and habitats.

There are many sources of pollution in marine systems.

A major source of marine pollution is agricultural activities, such as the use of fertilizers containing nitrogen and phosphorous. This pollutant can seep into groundwaters and be washed into the ocean as runoff, resulting in the spread of dead zones in coastal waters.

Another source of pollution comes from human waste which causes nutrient pollution and for countries with poor sanitaiton and inadequate sewage treatment can introduce bacteria, viruses and parasites into water systems and coastal waters, resulting in disease and infection.


Explore the full description of the data and model used in the Global OHI MODEL. Or, take a look at PRACTICAL GUIDANCE for advice on adapting the goal for future assessments and to learn how previous OHI+ assessments have modified this goal to address differences in data availability or priorities.

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