Answer:
Step-by-step explanation:
The Vaal River system supplies water to 60% of the economy and 45% of South Africa's population.” ... Symptoms of contact with e-coli-polluted water include skin irritations, infections and intestinal disorders. E-coli counts of 200 – 400 per 100ml of water represent a significant risk for gastrointestinal disorders.Sulfur dioxide and nitrous oxide emitted from factories and power stations enter river systems through acid rain. Sewage and effluent are discharged into rivers in some areas. Pollution can lower the pH of the water, affecting all organisms from algae to vertebrates. Biodiversity decreases with decreasing pH.11% from industries and 14% from mines. Agriculture has little influence on water quality and increased salinity and eutrophication are therefore the main quality problems. This catchment has sewerage, industrial and, as major contributors, mining return flows which also affect the quality of the Vaal River water.
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