Upon contact with soil, the rain water becomes surface water and after soaking in it may be called ground water. Thus insufficient protection of surface water against contamination with human and animal wastes may cause major water supply problems.

Pollutants mixed with water pass through permeable layers above the aquifer. Factories dump their waste directly into aquifers.

One-third of Americans — more than 102 million people — get their drinking water from public water systems that use groundwater.

Point sources release pollutants from discrete conveyances, such as a discharge pipe, and are regulated by federal and state agencies. The main point source dischargers are factories and sewage treatment plants, which release treated wastewater.

Groundwater depletion is primarily caused by sustained groundwater pumping. Some of the negative effects of groundwater depletion: drying up of wells. reduction of water in streams and lakes.

Groundwater overdraft can create new water quality problems or make existing groundwater pollution worse. As aquifer levels decline from chronic overdraft, natural and manmade pollutants can concentrate in the remaining groundwater, making it unsafe for irrigation or drinking without costly treatment.

Overpumping refers to the extraction of groundwater in excess of supply to a basin or aquifer, resulting in depletion of water resources. Overpumping of a well can lead to the intrusion of saline water if the well is near the sea coast.

The extreme use of groundwater resources can have serious concerns, such as uplifting and seismic activities, ecological environment deterioration, land subsidence, vegetation degradation, livelihoods for rural poor, and food security implications.

Desalination is not a perfected technology, and desalinated water can be harmful to human health as well. By-products of the chemicals used in desalination can get through into the “pure” water and endanger the people who drink it. Desalinated water can also be acidic to both pipes and digestive systems.