Final answer:
Groundwater is facing critical environmental problems, including ground subsidence, saltwater intrusion, and contamination due to various human activities such as overpumping and agriculture, which significantly affect water quality and availability.
Step-by-step explanation:
Important Environmental Problems Associated with Groundwater
Important environmental problems associated with groundwater include phenomena like ground subsidence, saltwater intrusion, contamination, and land subsidence. Ground subsidence refers to the gradual sinking of land surface over a large area, often due to the excessive withdrawal of groundwater. Saltwater intrusion occurs when overpumping of fresh water causes saltwater to encroach into freshwater zones, particularly near coastlines. Contamination of groundwater can arise from various pollutants including nitrates, pathogens, organic pollution, and heavy metals, compromising water quality and public health. Land subsidence poses a significant threat to structures and ecosystems as it changes the landscape and can lead to property damage.
Furthermore, the water supply crisis highlights a global scarcity of clean and sufficient water resources. Excessive groundwater pumping, referred to as groundwater mining, has led to depleted water tables, forcing deeper drilling, which often results in saline water being encountered. This can significantly affect the availability and quality of groundwater for potable and irrigation purposes.
Groundwater contamination is widespread. For instance, a study of the United States aquifers indicated that a considerable percentage of domestic wells contained contaminants above health benchmarks. Agricultural practices are a major non-point source of contaminants that include fertilizers, pesticides, and salts, leading to pollution of both surface water and groundwater.