Sources of water pollution

Some of the principal sources of water pollution are:

• Geology of aquifers from which groundwater is abstracted
• Industrial discharge of chemical wastes and byproducts
• Discharge of poorly-treated or untreated sewage
• Surface runoff containing pesticides or fertilizers
• Slash and burn farming practice, which is often an element within shifting cultivation agricultural systems
• Surface runoff containing spilled petroleum products
• Surface runoff from construction sites, farms, or paved and other impervious surfaces e.g. silt
• Discharge of contaminated and/or heated water used for industrial processes
• Acid rain caused by industrial discharge of sulphur dioxide (by burning high-sulphur fossil fuels)
• Excess nutrients are added (eutrophication) by runoff containing detergents or fertilizers
• Underground storage tank leakage, leading to soil contamination, and hence aquifer contamination
• Inappropriate disposal of various solid wastes and, on a localized scale, littering
• Oil spills