What is water pollution? Differentiate between groundwater and surface water pollution.

Water pollution refers to the contamination or degradation of water bodies, including rivers, lakes, streams, groundwater aquifers, and oceans, by harmful substances or pollutants. These pollutants can originate from various sources, including industrial discharges, agricultural runoff, urban sewage, improper waste disposal, and natural processes, leading to adverse effects on aquatic ecosystems, human health, and the environment.

Groundwater pollution occurs when contaminants infiltrate and accumulate in underground aquifers, which are layers of porous rock or soil that hold water beneath the Earth's surface. Common sources of groundwater pollution include leaking underground storage tanks, improper disposal of hazardous waste, septic system leaks, and agricultural chemicals such as pesticides and fertilizers. Groundwater pollution poses significant risks to human health as contaminated groundwater may be used for drinking water supply, irrigation, and industrial purposes, leading to exposure to harmful chemicals and toxins.

Surface water pollution, on the other hand, affects water bodies that are visible on the Earth's surface, such as rivers, lakes, streams, and oceans. Surface water pollution can result from a wide range of sources, including industrial effluents, municipal sewage discharge, runoff from urban areas, agricultural activities, and oil spills. Pollutants can enter surface water bodies directly through point sources such as discharge pipes or indirectly through non-point sources such as runoff from agricultural fields and urban streets. Surface water pollution can degrade water quality, harm aquatic ecosystems, and impair recreational activities such as swimming and fishing. Additionally, surface water pollution can impact human health through the consumption of contaminated water or the consumption of contaminated fish and seafood.

In summary, while both groundwater and surface water pollution involve the contamination of water bodies by harmful substances, they differ in their location and sources of contamination. Groundwater pollution occurs in underground aquifers and is often caused by activities that contaminate the subsurface environment, while surface water pollution affects visible water bodies and is typically the result of pollutants entering water bodies from various sources on the Earth's surface.