Don't even think about it!
The Pearl River Delta region, with its rivers and abundant water, is experiencing a severe drought!
Since the beginning of winter, due to the lack of local precipitation, the water from the West and East Rivers in the Pearl River Basin has continued to be less.
What's more, the "salty tide" is coming again!
Around the fifteenth day of the first month, the astronomical tide in the Pearl River Estuary was enhanced by the northeast wind of 6-7 magnitude, and the salt tide was strong;
"Less water, salty and strong tide", so that the water supply situation in the Pearl River Delta is extremely severe.
We can understand that the water is less, what is this salty tide?
Mostly in coastal areas, when the freshwater river flow is insufficient, the sea water flows backwards into the inland area through the river or other channels, the brackish water is mixed, and the salt content in the water reaches or exceeds 250 mg/l, forming a salt tide.
To put it simply, the water in the river should have flowed to the sea, and the result is that the amount of water in the river is too small.
The sea water flows backwards into the river, causing the fresh water salinity to exceed the standard.
In our country, the estuaries of the Yangtze, Qiantang and Pearl rivers will all have salty tides.
Reduced precipitation will cause salty tides to rise. The backfilling of seawater caused by salty tides requires the mobilization of fresh water upstream to suppress the backwater.
This has exacerbated drought in areas where precipitation had already decreased.
So let's leave it alone, okay?
Not really...
If the salt tide is not suppressed, and the salinity of fresh water exceeds the standard, it is not only a problem that our tap water is a little salty to drink.
The rise in salt content and chlorine content will also affect health and cause harm to the human body.
According to the data provided by the "Water Quality Standard for Domestic Drinking Water Sources", the chloride content of human drinking water should be less than 250 mg/L.
Drinking two liters of salt water is equivalent to eating a quarter of a pack of squeezed vegetables...
Short-term drinking is indeed not harmful, but if the salty tide is left unattended, resulting in residents drinking saltwater for a long time, it will cause harm to the elderly, patients with high blood pressure, heart disease, diabetes and other patients.
In addition to the residents, it will have an impact on our industry and agriculture.
The production of the steel industry requires that the chlorine content of water not exceed 20 mg/l, and the chlorine content of boiler water in power plants cannot exceed 300 mg/l.
Once the salt tide is backfilled, not only the production equipment is easy to oxidize, but the boiler and other containers are also easy to accumulate scale.
Agriculture is even more pronounced.
Salt water will cause the salinity in the groundwater and soil to increase, the general rice seedling stage, the chloride content of water needs to be less than 600 mg / l, beyond this standard, rice will stop growing, or even harvest!
These four factors have led to the arrival of salty tides
How much does drought and saltiness affect the Pearl River Delta?
According to Wang Lixin, director of the Guangdong Provincial Water Conservancy Department, at present, the backbone reservoirs in the Dongjiang River Basin of Guangdong Province have less water and less water storage, the salt tide is moving eastward, and the upward traceability power is stronger, and the Xinfengjiang Reservoir has been lower than the stagnant water level by 0.2 meters, which is the first time since the construction of the reservoir to ensure that the water supply is lower than the dead water level; the water supply in the Han River and eastern Guangdong is tightly balanced, and the water supply gap in Guangdong Province is about 900 million cubic meters.
"It is predicted that there will be less water this spring, and there will still be 5 obvious salt tides in the Dongjiang River Basin, and the pressure of salt and salt replenishment is relatively large, and the task of water supply security is arduous."
How to deal with salty tides?
In fact, every year, coastal areas will face the problem of salty tide upwards.
Now, the water conservancy department is scientifically mobilizing all aspects of the study of salt tide:
On the one hand, it accurately calculates when it rains, how much water can be stored, controls the water dispatch from a macro perspective, and judges the future form of salt tide as soon as possible; on the other hand, it proposes refined scheduling measures and temporary emergency plans for salting, and mobilizes the basins and reservoirs of the Pearl River to accurately suppress salt and make up for the lightness, and also proposes the plan of building dams and embankments to prevent seawater from entering the inland freshwater from the source.
Therefore, recently friends in the south, if the weather has been raining continuously recently, they should bear with it a little.
After all, from the perspective of replenishing water sources, this is also good news.
This article refers to the surging news, China Water Conservancy and other related content.
Editor: Junjie