Why is Groundwater important to Southern California?
Groundwater is critical to Southern California's water supply because its located at the bottom, this means that all of the runoff from Northern California ends up here. In an average year, 40% of CA water comes from groundwater, in times of drought, consumption can rise up to 60% or more. Groundwater is water from rain that seeps underground into pores between soil called aquifers. Many communities obtain their drinking water from aquifers by having water suppliers drill wells through soil and rock into aquifers to supply the public with drinking water. Some homes have their own private wells drilled on their property to tap this supply.
Why is Groundwater a Risky Source?
Groundwater can become contaminated in multiple ways. The most common is for rain or surface water to mix with contaminated soil making the toxic liquids seep into the ground and carry the pollution from the soil to the groundwater. Liquid hazardous substances themselves soak down through the soil or rock into the groundwater. Some liquid hazardous substances won't mix with the groundwater initially but remain in a pool within the soil or bedrock until runoff collects it. Toxic substances in groundwater comes from industries but some of it is from during the Gold Rush. Miners would use hazardous chemicals when handling gold and some of those chemicals are still found in groundwater. Hazardous substances in water can harm all living things. The most frightful are diseases in the human body.