Waterborne pathogens can enter coastal waters via leaking sewer pipes and untreated wastewater.
Sewage and untreated wastewaters are filled with microbes some of which are capable of causing diseases to humans and livestock if given the opportunity. Hence, the seeping of these waters into coastal water is a risk to humans who might want to swim or make use of coastal waters.
Precipitation, changing of tides and the interactions of marine organisms and plants will ordinarily not form pathways through which pathogens can gain access to coastal waters.
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