Salt water intrusi
Salt water intrusion
Saltwater intrusion is the movement of saline water into freshwater aquifers. Most often, it is caused by ground-water pumping from coastal wells, or from construction of navigation channels or oil field canals. The channels and canals provide conduits for salt water to be brought into fresh water marshes. Salt water intrusion can also occur as the result of a natural process like a storm surge from a hurricane. Saltwater intrusion occurs in virtually all coastal aquifers, where they are in hydraulic continuity with seawater.
Effect on drinking water
When fresh water is withdrawn at a faster rate than it can be replenished, the water table is drawn down as a result. This draw-down also reduces the hydrostatic pressure. When this happens near an ocean coastal area, salt water from the ocean is pulled into the fresh water aquifer. The result is that the aquifer becomes contaminated with salt water. This is happening to many coastal communities