Why is Zhuhai affected by the recent salty tide? What is a salty tide?

A salty tide is a natural disaster in which the salt content of water remains at or above 250 mg/l after seawater in coastal areas backs up into inland areas through rivers or other channels.

The salty tide usually occurs during the period from the winter solstice of the previous year to the clearing of the spring of the following year, and it is mainly caused by drought. The direct trigger of this salty tide is the successive years of drought in the land of southern Guangdong, but the rise in sea level and the uncontrolled sand mining of human beings also aggravate the spread of salty tide. The chloride concentration of seawater is generally higher than 5,000 mg/liter, and when a salty tide occurs, the chloride concentration in river water rises from a few milligrams per liter to more than 250 mg. Excessive salinity in the water can be harmful to the human body and should not be consumed by the elderly, patients with high blood pressure, heart disease and diabetes. High salinity in the water will also pose a threat to business production, production equipment is prone to oxidation, boilers are prone to scale build-up, while the salty tide will also cause an increase in salinity in the groundwater and soil, jeopardizing the survival of local plants.