World Water Day: Here’s what you need to know about groundwater

There is a kind of water, deep underground

It is "groundwater"

Our precious resources

March 22 is the 30th World Water Day

March 22-28 is the 35th "China Water Week"

The theme of this year's World Water Day is

“Cherish groundwater, cherish hidden resources”

Our parents have taught us to drink more water to keep healthy.

Growing up, people around me care about me

It all became "drink more hot water"

Doctors recommend drinking 8 glasses of water a day

But you know

Where does our drinking water come from?

What kind of groundwater is drinkable?

Where does our drinking water come from?

The water we currently use for daily life comes from multiple sources. One is surface water, such as water from rivers, lakes, and reservoirs; the other is groundwater.

Taking Beijing as an example, about 60% of tap water comes from deep groundwater, and about 40% comes from surface water such as the Miyun Reservoir.

What is groundwater?

There are nearly 1.4 billion cubic kilometers of water on Earth, of which seawater and salt water account for the vast majority, and more than 98% of fresh water is either in the ice caps at the Earth's poles or buried deep underground.

The water on Earth is constantly circulating. Part of it flows in the ocean, atmosphere and surface, while the other part goes underground and becomes groundwater. Most of the groundwater eventually flows into the ocean.

Groundwater refers to water stored in the rock gaps below the ground. In a narrow sense, it refers to water in the saturated aquifer below the groundwater surface.

Groundwater can be simply divided into shallow groundwater (about 60 meters below the surface) and deep groundwater (about 1000 meters below the surface).

Is groundwater drinkable?

Drinkable! Currently, groundwater drinking water is mainly obtained from deep groundwater.

However, not all surface water and groundwater can be used as sources of drinking water in my country. They must meet the relevant standards of the national "Groundwater Quality Standard" (GB/T14848-93).

The water quality of deep groundwater is better, with less suspended impurities, less organic matter and bacteria, and is not easily affected by the external environment. At present, the water quality of my country's groundwater drinking water sources is generally good.

Before domestic drinking water enters thousands of households, it must undergo disinfection, sterilization, filtration and other treatment processes at the water plant to meet national drinking water standards.

Will the groundwater be contaminated?

Yes! Once groundwater is polluted, even if the source of pollution is completely eliminated, it will take more than ten years or even decades for the water quality to recover.

The strata below the surface are complex and the groundwater flows extremely slowly. Therefore, groundwater pollution is characterized by a slow process, being difficult to detect and difficult to control.

In addition, over-exploitation of groundwater to meet the rapidly growing water demand has also brought about hazards such as land subsidence, water quality deterioration, and aquifer depletion.

Groundwater is a precious gift from nature.

So remember

Cherish and utilize groundwater resources scientifically!