EARTH SCIENCE
GROUNDWATER
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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near Richmond area where rocks still have salt in them
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high up in the mountains where rivers begin as headwaters
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the coast where saltwater trapped within cracks of rocks can be pumped by wells
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in the middle of the ocean
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Detailed explanation-1: -As sea levels rise along the coasts, saltwater can move onto the land. Known as saltwater intrusion, this occurs when storm surges or high tides overtop areas low in elevation. It also occurs when saltwater infiltrates freshwater aquifers and raises the groundwater table below the soil surface.
Detailed explanation-2: -While intermixing of freshwater and seawater is one of the main causes of saltwater intrusion in coastal B.C., groundwater within deeper aquifers may also be salty due to geologic processes and interactions between rocks and water over a long time period (e.g. millennia).
Detailed explanation-3: -Saltwater intrusion occurs by many ways, including lateral encroachment from coastal waters and vertical movement of saltwater near discharging wells. The intrusion of saltwater caused by withdrawals of freshwater from the groundwater system can make the resource unsuitable for use.
Detailed explanation-4: -This phenomenon is caused by the depletion of fresh groundwater due to pumping, wells, overuse of water by coastal populations and agriculture, and by changing the natural path of water flow. It can be exacerbated by sea level rise and storm surge. As freshwater is depleted, saltwater rushes in to take its place.